1. What are the most common malignant solid abdominal tumors in children?

Show answer
Neuroblastomas, Wilms’ tumors, and hepatoblastomas, in that order. Neuroblastomas are derived from neural crest tissue; in the abdomen, they originate from the adrenal glands and paraspinal sympathetic ganglia. Wilms’ tumor (nephroblastoma) derives from the kidney, and hepatoblastomas originate in the liver.

2. Is it tough to differentiate Wilms’ tumor from neuroblastomas clinically?

Show answer
Yes. Both tumors present as an asymptomatic abdominal mass. The differences are summarized in Table 87-1. In addition, because neuroblastomas produce hormones, affected children may exhibit flushing, hypertension (catecholamine release), watery diarrhea, periorbital ecchymosis, and abnormal ocular movements.
Table 87-1. DIFFERENTATION BETWEEN WILMS’ TUMOR AND NEUROLASTOMA

3. How are Wilms’ tumors and neuroblastomas treated?
Table 87-2. TREATMENT OF WILMS’ TUMOR AND NEUROBLASTOMA

4. What are the major prognostic factors in neuroblastomas and Wilms’ tumor?

In neuroblastomas, age at presentation is the major prognostic factor. Children younger than 1 year have an overall survival rate > 70%, whereas the survival rate for children older than 1 year is < 35%. Shimada proposed a prognostic classification based on evaluation of histologic parameters (tumor differentiation, mitosis-karyorrhexis index [MKI]) as well as age. Aneuploid tumors, tumors with low MKI, and tumors with < 10 copies of the n-myc gene also have better outcomes.

Age is also important in children with Wilms’ tumors, but the prognosis is better because the tumors are more readily excised and much more sensitive to chemotherapy.
5. What are the differences between hepatoblastomas and hepatocellular carcinomas? How are the tumors treated?
Hepatoblastomas usually occur in infants and young children, whereas hepatocellular carcinoma usually occurs in children older than 10 years. Hepatocellular carcinoma usually is associated with cirrhosis and hepatitis B and is histologically identical to the adult form. Surgical resection is the primary therapy for both tumors. Hepatoblastomas often have a good response to adjunctive chemotherapy, whereas hepatocellular carcinoma rarely responds to chemotherapy.

36. What are some of the anatomic issues related to inguinal hernias?

Show answer
At issue is the iliopubic tract, which is central to the Anson/McVay anatomic description of the inguinal area and featured in the McVay Cooper’s ligament repair. Although the McVay repair is used in England, the iliopubic tract is not referred to or described in English anatomic texts.

The term conjoined tendon, although commonly used, is considered by many to be anatomically inaccurate and misleading. The internal oblique and transversus abdominis muscles that make up the conjoined tendon are obvious and can be used surgically either alone or together. The tendinous edge of the transversus abdominis muscle and the tendinous edge of the internal oblique muscle start at their insertion on the pubic tubercle and course laterally and superiorly to the medial edge of the internal ring. At this point, the tendinous elements diminish, leaving only muscle tissues, and continue laterally and superiorly to their origins.
Whether the lacunar ligament or the iliopubic tract defines the medial border of the femoral canal is controversial. The compromise position is that the iliopubic tract is the border whereas in the normal unstretched state, the lacunar ligament (Gimbernat’s ligament) is the border in the presence of hernia (stretched state). At surgery it is enough to say that a palpable, visible curved ligament is present and used in some femoral repairs.

37. What are some surgical issues in the repair of inguinal hernias?

Show answer

The controversy over implanting mesh, as in the Lichtenstein repair, has been resolved in favor of mesh. Another controversy concerns the use of the laparoscope for hernia repair. A further issue is intra-abdominal or preperitoneal placement of mesh. At present, most surgeons accept laparoscopic repair as an alternative for preperitoneal hernia repair. The indications for a preperitoneal approach to hernia repair are still being defined, although the preperitoneal approach is acceptable for repair of recurrent hernia and unusually large or difficult hernias. The preperitoneal approach is used with increasing frequency for repair of femoral hernias. The repair should be appropriate to the circumstance of the hernia. Thus, hernia location and size as well as the patient’s age, general condition, and recurrence status should be factored into the strategy of repair.

References
BIBLIOGRAPHY
1. Avisse C, Delattre JF, Flament JB: The inguinal rings. Surg Clin North Am 80:49-69, 2000. Medline Similar articles
2. Avisse C, Delattre JF, Flament JB: The inguinofemoral area from a laparoscopic standpoint. History, anatomy, and surgical applications. Surg Clin North Am 80:35-48, 2000. Medline Similar articles
3. Bendavid R, Howarth D: Transversalis fascia rediscovered. Surg Clin North Am 80:25-33, 2000. Medline Similar articles
4. Collaboration EH: Laparoscopic compared with open methods of groin hernia repair: Systematic review of randomized controlled trials. Br J Surg 87:860-867, 2000. Medline Similar articles Full article
5. Collaboration EH: Mesh compared with non-mesh methods of open groin hernia repair. Systematic review of randomized controlled trials. Br J Surg 87:854-859, 2000. Medline Similar articles Full article

1. “Groin” hernia refers to which three hernias?

Show answer
Direct and indirect inguinal hernias and femoral hernias.

2. Francois Poupart, a French surgeon and anatomist (1616-1708), described a ligament that bears his name. What is the anatomic name of the Poupart ligament?

Show answer
Inguinal ligament, which is a key element in most groin hernia repair.

3. Franz K. Hesselbach, a German surgeon and anatomist (1759-1816), described a triangle that is the common site of direct hernias. What are the anatomic margins of Hesselbach’s triangle?

Show answer
The triangle is defined inferiorly by the inguinal ligament, superiorly by the inferior epigastric vessels, and medially by the rectus fascia. The transversalis fascia forms the floor of the triangle. The original description used Cooper’s ligament as the inferior limit but because of the common use of the anterior approach to hernias, the more apparent inguinal ligament was substituted as the inferior limit of the triangle. With the increasing use of preperitoneal approaches to hernia repair, Cooper’s ligament is again much more apparent and useful as an anatomic touchstone.

4. Sir Astley Paston Cooper, an English surgeon and anatomist (1768-1841), described a ligament bearing his name. What is the anatomic name for the ligament and the proper name of Cooper’s ligament repair?

Show answer
The anatomic name of Cooper’s ligament is iliopectineal ligament. The Cooper’s ligament repair or McVay repair was popularized by Chester McVay (1911-1987). With Barry Aston, professor of anatomy at Northwestern University, McVay provided the modern description of the groin anatomy.

5. Antonio de Gimbernat, a Spanish surgeon and anatomist (1734-1816), had his interesting name attached to the lacunar ligament, which marks the medial margin of a groin area opening. What is the opening? What hernia protrudes into this opening?

Show answer
The opening is the femoral canal, which is defined medially by the lacunar ligament, anteriorly by the inguinal ligament, posteriorly by the pectineal fascia, and laterally by the femoral vein. A femoral hernia protrudes into the femoral canal.

6. Indirect inguinal hernia (particularly in children) and hydrocele are associated with which congenital abnormality?

Show answer
Persistence of an open processus vaginalis, in the case of a hernia, allows descent of bowel into the inguinal canal. With fluid accumulation, partial obstruction presents as a hydrocele of the spermatic cord.

7. What are the diagnostic criteria for hernia in an infant or child?

Show answer

* Inguinal, scrotal, or labial lump that may or may not be reducible
* History of a lump seen by a health care provider
* History of a lump seen by the mother
* The “silk sign” (the feeling of rubbing together two surfaces of silk cloth when gently rubbing together the two surfaces of a hernia sac)
* An incarceration sometimes felt on rectal examination

8. What can be done to reduce an incarcerated hernia in an infant or child?

Show answer
The four-point program is easier said than done, but it is worth the effort:

1. Sedate the patient.
2. Place the patient in the Trendelenburg position.
3. Apply a cold pack (over petroleum gauze to avoid skin injury) in inguinal area.
4. In the absence of spontaneous reduction-and if the patient is quiet-use gentle manipulation.

9. How often can incarceration be successfully reduced? What should be done next?

Show answer
About 80% of incarcerated hernias can be reduced in children; in adults, the percentage is lower. Despite the fact that 80-90% of inguinal hernias occur in boys, most incarcerations occur in girls. The hernia should be repaired electively within a few days after incarceration. The 20% of hernias that are still incarcerated are operated immediately.

10. What is a Bassini repair?

Show answer
The Bassini repair sutures together the conjoined tendon and the shelving edge of the inguinal ligament up to the internal ring (Figure 56-1). This classic procedure, introduced in 1887 at the Italian Society of Surgery in Genoa, revolutionized hernia repair. Until recently, it has been the standard of repair. After graduation from medical school and while fighting for Italian independence, Eduardo Bassini (1844-1924) was bayoneted in the groin and, as a prisoner, was hospitalized for months with a fecal fistula.

Figure 56-1 The standard right inguinal hernia repair using the conjoined tendon and inguinal ligament.

11. What is the recurrence rate with indirect and direct hernias that have been repaired with classic Bassini repair technique?

Show answer
Over a follow-up period of 50 years, the recurrence rate of adult indirect hernias is 5-10%; of direct hernias, 15-30%.

12. Describe a McVay hernia repair.

Show answer
The line of interrupted sutures starts at a the pubic tubercle and joins the tendinous arch of the transversus abdominis muscle to Cooper’s ligament up to the femoral canal. At this point, two or three transitional sutures are placed from Cooper’s ligament to the anterior femoral fascia, effectively closing the medial extreme of the femoral canal. The final set of sutures joins the transversus abdominis arch and the anterior femoral fascia. The stitches usually incorporate the inguinal ligament at the upper limit of the repair, the site of the new internal inguinal ring and cord structures. About 15 years ago, McVay described laying in a mesh patch and stitching it, at its periphery, to the same anatomic structures. This application of mesh closely resembles the Lichtenstein repair (see question 17), except that it uses Cooper’s ligament.

13. For what type of hernias is the McVay Cooper’s ligament repair most useful?

Show answer
Femoral and direct hernias.

14. What is the Shouldice repair?

Show answer
The Shouldice repair, popularized at the Shouldice Clinic near Toronto, imbricates or overlays the transversalis fascia and conjoined tendon with four continuous lines, using two fine-wire sutures. The suture tract runs from the pubic tubercle to a new internal ring. Care is taken with the inferior epigastric vessels. The result is layered approximation of the conjoined tendon to the inguinal ligament tract.

15. What is the reported recurrence rate for the Shouldice repair?

Show answer
The recurrence rate is 1%, the lowest reported rate for nonmesh repairs of inguinal hernias in adults.

16. For what type of groin hernia is the Shouldice repair not appropriate?

Show answer
Femoral hernia.

17. Describe the Lichtenstein repair.

Show answer
The Lichtenstein repair consists of a sutured patch of polypropylene mesh (Marlex, C.R. Bard, Inc., Covington, GA) that covers Hesselbach’s triangle and the indirect hernia area. It is considered a tension-free repair because the mesh is sutured in place without pulling ligaments or tissues together as in all other repairs. The mesh is divided at its upper end to wrap closely around the spermatic cord and its associated structures in the normal position of the internal inguinal canal. The Lichtenstein procedure is rapidly becoming the most widely used repair of adult inguinal hernia. The reported recurrence rate is < 1%.

18. What are the advantages of using the Marlex mesh?

Show answer
Central to acceptance and success of the Lichtenstein hernia repair has been the development of and experience with the Marlex mesh. The monofilament mesh is strong, inert, and resistant to infection. The interstices are rapidly and completely infiltrated with fibroblasts, and the mesh is not subject to deterioration, rejection, or fragmentation. (See Figure 56-2.)

19. For what groin area is the Lichtenstein repair not appropriate?

Figure 56-2 The Marlex mesh repair of a right inguinal hernia. Note that the same structures are used but not brought together; thus, the name of the “tension-free” repair.

20. Which type of repair is acceptable for the femoral hernia?

Show answer
Several different repairs can be used. Mesh in the form of a plug can be inserted into the femoral canal and fixed in place. A McVay Cooper’s ligament repair can be done. A preperitoneal approach to the hernia can be used to suture or plug the defect. A suture repair or a sartorius facial flap applied from below the inguinal ligament in a femoral approach also may be used. The preperitoneal approach is increasingly used for complicated inguinal and femoral hernias.

21. What is the preperitoneal or Stoppa procedure?

Show answer
The preperitoneal or Stoppa procedure is a groin hernia repair on the internal side of the abdominal wall between the peritoneum and fascial surfaces that do not open into the peritoneal cavity. The anatomic landmarks are very different and initially quite challenging to surgeons accustomed to the external abdominal wall approach. The technique is suited for recurrent hernias in which scarring and obliterated anatomy increase the risk of cord injury and recurrence. Other problems such as large hernias and femoral hernias are corrected with this approach. Conceptually, the laparoscopic hernia repair uses the same approach. (See Figure 56-3.)

22. Where are the spaces of Retzius and Bogros? Why are they increasingly important?

Show answer
Retzius’ space is between the pubis and the urinary bladder. Bogros’ space is between the peritoneum and the fascia and muscle planes on the posterior aspect of the abdominal wall below the umbilicus and down to Cooper’s ligament. Laterally, the space goes to the iliac spines. In either the open Stoppa procedure or the laparoscopic preperitoneal repair, the spaces of Retzius and Bogros are developed for mesh placement and surgical exposure.

23. How tight around the spermatic cord should a surgically fashioned, internal inguinal ring be?

Show answer
About 5 mm, which http://surgeryprocedure.info/wp-admin/media-upload.php?post_id=285&type=image&TB_iframe=true&width=640&height=525
Add an Imageis less than a fingertip and more than a forceps tip.

Figure 56-3 The different appearance and landmarks are seen in the anterior view (above) and the posterior view (below) of the inguinal-femoral area. In the posterior view the importance of the inferior epigastric vessels, bladder, and Cooper’s ligament as anatomic landmarks is apparent.

24. What is the common fascial defect of larger indirect and all direct inguinal hernias?

Show answer
Weakness or attenuation of the transversalis fascia.

25. On examination, the femoral hernia may be confused with what other inguinal hernia?

Show answer
The femoral hernia may be confused with a direct inguinal hernia because of the tendency of the femoral hernia to present at the lateral edge of the inguinal ligament.

KEY POINTS: TYPES OF INGUINAL HERNIA REPAIR

1. The Bassini repair sutures together the conjoined tendon and the shelving edge of the inguinal ligament up to the internal ring.
2. The McVay repair is most useful for femoral and direct hernias.
3. The Shouldice repair imbricates the transversalis fascia and conjoined tendon with four continuous lines, using two fine-wire sutures (not appropriate for femoral hernias).
4. The Lichtenstein repair consists of a sutured patch of polyprolene mesh that covers Hesselbach’s triangle and the indirect hernia sac.

26. What is the difference between an incarcerated and a strangulated hernia?

Show answer
Incarcerated: structures in the hernia sac still have a good blood supply but are stuck in the sac because of adhesions or a narrow neck of the hernia sac.
Strangulated: herniated structures, such as bowel or omentum, have lost their blood supply because of anatomic constriction at the neck of the hernia. The herniated, ischemic tissue is, therefore, in various stages of gangrenous changes. Strangulated hernias are surgical emergencies.

27. What operation is done for an uncomplicated indirect infant hernia?

Show answer
High ligation of the hernia sac.

28. What operation is done for an uncomplicated indirect hernia in young adults?

Show answer
The appropriate operation consists of high ligation and possibly one or two stitches in the transversalis fascia to tighten the internal ring. This is the basic Marcy technique, developed by Henry Orlando Marcy (1837-1924); it is smaller and more anatomically focused than the Bassini repair.

29. What operation is done for an uncomplicated but sizable direct hernia in elderly adults?

Show answer
Traditionally, the Bassini or McVay repair was chosen. More recently, because of the low recurrence rate, the Shouldice or Lichtenstein repair is favored.

30. What organ systems should be reviewed with particular care in the work-up of patients with hernia (especially elderly patients with recent onset of hernia)?

Show answer
The gastrointestinal, urinary, and pulmonary systems should be reviewed with particular care. One is looking for causes of chronic strain or sudden forces that may have induced the hernia. Straining during defecation or urination, unusual coughing, or difficulty with breathing, if corrected, may be of great value to the patient and reduce the chance of recurrent hernia.

31. What is a sliding hernia?

Show answer
A sliding hernia is formed when a retroperitoneal organ protrudes (herniates) outside the abdominal cavity in such a manner that the organ itself and the overlying peritoneal surface constitute a side of the hernia sac.

32. What organs can be found in sliding hernias?

Show answer

* Colon
* Cecum
* Appendix
* Ovary
* Bladder
* Fallopian tubes
* Uterus (rare)

33. What are common operative and postoperative complications of hernia repairs?

Show answer
Intraoperative complications

* Injury to the spermatic cord, especially in children
* Injury to the spermatic vessels, resulting in atrophy or acute necrosis of testes
* Injury to the ilioinguinal nerve, genitofemoral nerve, and lateral femoral cutaneous nerve (the lateral femoral cutaneous nerve is uniquely vulnerable in laparoscopic and properitoneal procedures)
* Injury to the femoral vessels

Postoperative complications

* Infection-high risk in children with diaper rash and patients with bowel injury or necrosis
* Hematoma-should resolve in time
* Nerve injury-the nerve is not always divided and, with time, may improve. If pain persists, try lidocaine block for both diagnosis and treatment. If a nerve block is not successful, one may consider reexploration to free the nerve from scar or to excise a postsurgical neuroma.

34. What are the common sites of hernia recurrence?

Show answer
Direct hernias often recur at the pubic tubercle. Indirect hernias recur at the internal ring. The cause is usually related to poorly placed or insufficient stitches. Other possible causes include infection, poor tissue, poor collagen formation, or too much tension at the surgical suture line. A single line of repair under moderate tension fails in a significant number of patients, regardless of adequacy of repair or healing process. Tension is almost always bad in surgery.

35. How long should the patient avoid heavy lifting after a hernia repair?

Show answer
The standard advice for decades has been 6 weeks. The current advice varies from no limitation with the Lichtenstein or preperitoneal repairs to 6 weeks for a Bassini repair. The self-limitation of pain is an excellent guide.

29. What is the most common clinical presentation of a pilonidal sinus?

Show answer
Pain and swelling in the sacrococcygeal region, which typically are associated with a (sometimes several) chronic draining sinus tract.

30. Is pilonidal disease acquired or congenital?

Show answer
Acquired. Hair follicles in the midline sacrococcygeal area enlarge and become infected, resulting in an abscess.

31. How is acute pilonidal abscess treated?

Show answer
Incision and drainage (like a fistula in ano, it is necessary to excise the whole tract).

32. What is the definitive therapy for pilonidal disease?

Show answer
Excision of the entire pilonidal cavity and associated sinus tracts down to the fascia with primary or delayed closure.

33. What theory explains the rarity of pilonidal disease after age 40 years?

Show answer
Changes in body habitus.

References
BIBLIOGRAPHY
1. Beck DE, Wexner SD (eds): Fundamentals of Anorectal Surgery. Philadelphia, W.B. Saunders, 1998.
2. Cho DV: Endosonographic criteria for an internal opening of fistula-in-ano. Dis Colon Rectum 42:515-518, 1999.
3. Cintron JR, Park JJ, Orsay CP, et al: Repair of fistulas-in ano using fibrin adhesive: Long-term follow-up. Dis Colon Rectum 43:944-949, 2000. Medline Similar articles
4. Corman ML: Anal fistula. In Corman ML: Colon and Rectal Surgery, 4th ed. Philadelphia, Lippincott-Raven, 1998, pp 238-271.
5. Hodgkin W: Pilonidal sinus disease. J Wound Care 7:481-483, 1998. Medline Similar articles
6. Law WL, Chu KW: Triple rubber band ligation for hemorrhoids: Prospective randomized trial of local anesthetic injection. Dis Colon Rectum 42:363-366, 1999. Medline Similar articles
7. Park JJ, Cintron JR, Orsay CP, et al: Repair of chronic anorectal fistulae using commercial fibrin sealant. Arch Surg 135:166-169, 2000.
8. Sentovich SM: Fibrin glue for all anal fistulas. J Gastrointest Surg 5:158-161, 2001. Medline Similar articles Full article

21. What are hemorrhoidal tissues, and what are their normal functions?

Show answer
Hemorrhoids are cushions of vascular tissue that contribute to anal continence and protect the sphincter mechanism during defecation. Hemorrhoids are not veins, but sinusoids. Bleeding originates from presinusoidal arterioles, thus explaining the bright red arterial color.

22. What are the most common causes of pathologic hemorrhoids?

Show answer
Constipation, prolonged straining, pregnancy, and internal sphincter dysfunction.

23. What is the most important difference between internal and external hemorrhoids?

Show answer
Whereas internal hemorrhoids are located above the dentate line with visceral innervation, external hemorrhoids are located below the dentate line with somatic innervation. Ablation of internal hemorrhoids causes a pressure sensation with an urge to defecate, but a similar approach to external hemorrhoids causes excruciating pain.

24. What are the most common complaints associated with pathologic internal hemorrhoids?

Show answer
Bleeding, mucus discharge, and prolapsing tissue.

25. What are the most common complaints associated with external hemorrhoids?

Show answer
Pain, inflammation, thrombosis, and difficulty with anal hygiene.

26. Are there any treatment options for symptomatic internal hemorrhoids based on identifiable physical characteristics?

Show answer
Yes. Treatment is based on the degree of prolapse:

Grade 1: None
Grade 2: Spontaneous reduction
Grade 3: Manual reduction
Grade 4: Unreducible

27. How are patients with symptomatic grades 2 and 3 and occasionally grade 4 internal hemorrhoids treated?

Show answer
Diet and stool bulking, rubber band ligation, injection sclerotherapy, cryotherapy, infrared photocoagulation, anal dilatation, or electrocautery.

28. What is the last-resort treatment for recalcitrant symptomatic internal hemorrhoids or combined internal and external hemorrhoids?

Show answer
Operative hemorrhoidectomy.

14. What is the most common location for idiopathic anal fissure?

Show answer
90% are posterior, and 10% are anterior.

15. What are the most common symptoms of anal fissure?

Show answer
Tearing anal pain and bleeding with bowel movements.

16. What is the underlying pathophysiology of fissure in ano?

Show answer
Local trauma to the anal canal, internal anal sphincter dysfunction, and ischemia.

17. What is the differential diagnosis for anal fissure, especially if atypical in location?

Show answer
Anorectal abscess, thrombosed hemorrhoid, inflammatory bowel disease, or malignancy.

18. How do you best diagnose anal fissure?

Show answer
By clinical history and visual inspection-not by digital examination or anoscopy (which serves only to turn a friendly patient into an irate one).

19. What are the nonoperative treatment options?

Show answer
High-fiber diet; stool-bulking agents; increased hydration; frequent, warm sitz baths; and topical agents containing anti-inflammatory agents, local anesthetics, and vasodilators (nitroglycerin).

20. What is the most common operation performed to treat intractable fissure in ano?

Show answer
Fissurotomy with lateral internal anal sphincterotomy.
KEY POINTS: ANAL FISSURE

1. Ninety percent of idiopathic anal fissures are posterior and 10% are anterior.
2. The most common symptoms are tearing anal pain and bleeding with bowel movements.
3. The diagnosis involves visual inspection-not by digital exam or anoscopy.
4. Nonoperative treatment includes high-fiber diet, warm sitz baths, and topical agents containing anti-inflammatory agents, local anesthetics, and vasodilators.
5. The most common operation is a fissurotomy with lateral internal anal sphincterotomy.

5. What is the most common cause of anorectal abscess?

Show answer
Ninety percent result from cryptoglandular infection.

6. What are the four potential anorectal spaces used to classify anorectal abscesses?

Show answer

1. Perianal (area of the anal verge)
2. Ischiorectal (area lateral to the external sphincter muscles, extending from the levator ani muscles to the perineum)
3. Intersphincteric (area between the internal and external sphincter muscles, continuous inferiorly with the perianal space and superiorly with the rectal wall)
4. Supralevator (area superior to the levator ani muscles, inferior to the peritoneum, and lateral to the rectal wall)

7. Define fistula in ano.

Show answer
A fistula is an abnormal communication between any two epithelial-lined surfaces. The internal opening of the fistula in ano involves the anoderm at the dentate line, whereas the external orifice is located at the anal margin.

8. What is the incidence of fistula in ano after appropriate surgical incision and drainage of acute anorectal abscesses?

Show answer
50%.

9. What is the most important factor leading to the successful surgical eradication of anorectal abscesses or fistulas?

Show answer
You must know anorectal anatomy, including the potential spaces (just memorize the answers to questions 4 and 6).

10. What is Goodsall’s rule?

Show answer
The location of the internal opening of an anorectal fistula is based on the position of the external opening. An external opening posterior to a line drawn transversely across the perineum originates from an internal opening in the posterior midline. An external opening, anterior to this line, originates from the nearest anal crypt in a radial direction.

11. What is the most important determinant of successful surgical treatment of fistula in ano?

Show answer
Identification of the internal openings.

12. What is a seton?

Show answer
A seton is a heavy suture placed through the fistulous tract that is then serially tightened, allowing slow, controlled transection of the sphincter. The associated fibrous reaction maintains sphincter integrity. Although associated pain is a limiting factor in its use, the technique can effectively change a high fistula into a low fistula with minimal risk of incontinence.

13. What is the role of fibrin glue in the management of anal fistula?

Show answer
Theoretically, the use of fibrin sealant represents an attractive alternative to the morbidity of operative treatment. However, although preliminary results support a marked decrease in postoperative pain and discomfort, 1-year recurrence rates are often > 50%.

1. What aspect of the initial patient encounter is most important in the diagnosis of anorectal disease?

Show answer
Clinical history, including duration of complaints, exacerbating or alleviating issues, precipitating events, dietary and bowel habits, and current or previous treatments. This may not sound glamorous, but you will never encounter a more grateful patient than one whose rectal problem you have solved.

2. What is the most common cause of painless, bright red blood per rectum? Show answer
Internal hemorrhoids.

3. What are the proximal and distal anatomic landmarks of the anal canal? What is its average length?

Show answer
The anal canal starts at the anorectal junction (which is the upper border of the internal sphincter muscle or puborectalis muscle) and ends at the anal verge. The average length is only 3-4 cm. The midpoint of the anal canal is called the dentate line.

4. What is the anatomic and surgical significance of the dentate line?

Show answer
The dentate line is the location of the anal crypts that drain the intramuscular and intersphincteric anal glands, which are the site of anorectal abscesses and fistulas in ano. Above the dentate line, the anal canal receives visceral innervation (involuntary control), is covered by columnar epithelium, and is the origin of internal hemorrhoids. Below the dentate line, the anal canal receives somatic innervation (voluntary control), is lined with squamous epithelium, and is the location of external hemorrhoids.

Show answer
Lung, breast or prostate, and colon cancer.

2. List a few of the presenting symptoms of patients with colorectal cancer.

Show answer
Intermittent rectal bleeding, vague abdominal pain, fatigue secondary to anemia, change in bowel habits, constipation, tenesmus, and perineal pain.

3. What options are available to evaluate a patient who has guaiac-positive stools?

Show answer
To evaluate the entire colon and rectum, one may perform a barium enema and proctoscopy or a colonoscopy. Colonoscopy is 10 times more expensive but is more sensitive for lesions < 1 cm.

4. List at least five risk factors for colorectal cancer.

Show answer
Prior adenomatous polyps, family history of colorectal cancer, age older than 40 years, chronic ulcerative colitis, Crohn’s colitis, history of colon cancer, exposure to pelvic radiation for prostate or cervical cancer, and familial polyposis. Hamartomatous polyps (Peutz-Jeghers syndrome), inflammatory polyps, and hyperplastic polyps are not considered premalignant.

5. What are the current screening recommendations of the American Cancer Society for colorectal cancers?

Show answer
A yearly digital rectal examination with testing for occult blood for patients age 40 years and older. Additionally, for patients older than age 50 years, a flexible sigmoidoscopy is recommended every 3-5 years.

6. In what part of the colon or rectum are most cancers found?

Show answer
Historically, there has been a higher incidence of cancers in the rectum and left colon. However, over the past 50 years, there has been a gradual shift toward an increased incidence of right colon cancers. This change in pattern may reflect improvement in early detection.

7. Surgical options for colorectal cancer are dependent on the tumor location. What operation should be performed for a patient with a lesion at 25 cm from the anal verge?

Show answer
A sigmoid colectomy.
8. What about a lesion at 9 cm from the anal verge? Show answer
A low anterior resection (LAR).
9. What about a lesion at 4 cm from the anal verge? Show answer
An abdominoperineal resection (APR). This requires a permanent colostomy.

10. What is the significance of finding adenomatous polyps in a patient’s colon?

Show answer
KEY POINTS: COLORECTAL CARCINOMA

1. Presenting symptoms may include intermittent rectal bleeding, vague abdominal pain, fatigue secondary to anemia, change in bowel habits, constipation, tenesmus, and perineal pain.
2. The current recommendations of the American Cancer Society for screening are a yearly digital rectal exam with testing for occult blood at age 40 years and for patients over 50 a flexible sigmoidoscopy every 3-5 years.
3. Patients with lymph node involvement should receive chemotherapy postoperatively to treat micrometastases.

This patient is six times more likely to develop colorectal cancer than a patient without polyps. Evidence suggests that all colon cancers arise from adenomatous polyps. The “adenoma-carcinoma sequence” describes this transformational process. Patients with familial adenomatous polyposis (FAP) typically harbor more than 100 polyps, which cover the colonic mucosa. If these patients go untreated, they will, without exception, develop adenocarcinoma of the colon by age 40 years.

11. How does the surgeon prepare the patient’s colon for an operation?

Show answer
Bowel preparation includes both a mechanical cleansing and appropriate antimicrobial prophylaxis. This combination has resulted in significant decrease in morbidity and mortality from colon surgery. Mechanical cleansing can be accomplished by lavage with polyethylene glycol (Go-Lytely) or a combination of cathartics and enemas (Fleet’s Prep).
Antimicrobial prophylaxis should cover the expected aerobic and anaerobic flora of the gut. Significant controversy exits over whether the antibiotics should be given enterally (e.g., neomycin, 1 g, and metronidazole [Flagyl], 1 g, three times orally at 4-hour intervals the evening before surgery) or parenterally (e.g., cefotetan, 2 g intravenously within 1 hour before surgery). Many clinicians give both to obtain both intraluminal and systemic protection.

12. What is Dukes’ staging system?

Dukes A – Tumor confined to bowel wall
Dukes B – Tumor invading through the bowel wall
Dukes C – Tumor cells found in the regional lymph nodes

In 1932, Dr. Dukes described a staging system for rectal cancer. He originally described the following: Since his original article was published, this classification has been modified several times. One of the most commonly used modifications is the inclusion of Dukes’ D stage, which indicates distant metastases.

13. Which patients with colorectal cancer require adjuvant (postoperative) therapy?

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Patients with lymph node involvement (Dukes’ C) should receive chemotherapy postoperatively to treat micrometastases. Two large studies have documented a survival advantage for these patients. However, no studies have documented a survival advantage for patients with Dukes’ B disease treated with chemotherapy.
Patients with rectal cancer with a significant chance of local recurrence (Dukes’ B and C) should be treated with radiation therapy. This may be given preoperatively, postoperatively, or with a combined “sandwich” technique.

References
WEB SITE
http://www.nejm.org
BIBLIOGRAPHY
1. Colorectal Cancer Collaborative Group: Adjuvant radiotherapy for rectal cancer: A systematic overview of 22 randomised trials involving 8507 patients. Lancet 358:1291-1304, 2001.
2. Jass JR: Pathogenesis of colorectal cancer. Surg Clin North Am 82:891-904, 2002. Medline Similar articles
3. Levin B, Brooks D, Smith RA, Stone A: Emerging technologies in screening for colorectal cancer: CT colonography, immunochemical fecal occult blood tests, and stool screening using molecular markers. CA Cancer J Clin 53:44-55, 2003. Medline Similar articles
4. Lynch HT, de la Chapelle A: Hereditary colorectal cancer. N Engl J Med 348:919-932, 2003. Medline Similar articles
5. National Institutes of Health Consensus Conference: Adjuvant therapy for patients with colon and rectal cancer. JAMA 264:1444-1450, 1990.
6. Ransohoff DF: Screening colonoscopy in balance issues of implementation. Gastroenterol Clin North Am 31:1031-1044, 2002. Medline Similar articles
7. Salz LB, Minsky B: Adjuvant therapy of cancers of the colon and rectum. Surg Clin North Am 82:1035-1058, 2002.
8. US Multisociety Task Force on Colorectal Cancer: Colorectal cancer screening and surveillance: Clinical guidelines and rationale-update based on new evidence. Gastroenterology 124:544-560, 2003.

1. What are polyps?

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A polyp is an elevation of the mucosal surface that can occur anywhere in the gastrointestinal (GI) tract. Two thirds of polyps occur in the rectosigmoid and descending colon.

2. What are the major types of polyps?

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1. Pedunculated polyps have a head attached by a stalk to the mucosa of the colon or rectum. The stalk usually is covered with normal mucosa.
2. Sessile polyps rest on a broad base.

In both types, the muscularis mucosa is an important landmark for differentiating invasive from noninvasive lesions. Lymphatics and veins do not extend across the muscularis mucosa. Submucosal lesions such as carcinoids and lipomas may resemble colorectal polyps.

3. At what age do polyps occur?

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Adenomatous colorectal polyps occur infrequently under the age of 30 years. The incidence increases with age. However, autopsy series report a microscopic frequency as high as 70% in patients older than age 45 years. The clinical incidence is 25% for persons older than age 60 years.

4. Which polyps have no malignant potential?

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Hyperplastic (metaplastic) polyps are small (1-5 mm) and constitute > 90% of the polyps in the colon and rectum. Unlike adenomatous polyps, hyperplastic polyps are caused by failure of mucosal cells to spread over the mucosal lumen. These cells then accumulate on the luminal surface, forming a polyp.
Hamartomas are collections of normal tissue in abnormal places (within the colonic mucosa).
Inflammatory polyps are common in diseases such as ulcerative colitis, Crohn’s disease, and schistosomiasis. They represent islands of healed or healing mucosal epithelium that are not permanent. The appearance of inflammatory polyps actually reflects the severity of the underlying disease. Lipomas may occur in polypoid form with head and stalk.

5. Which polyps have malignant potential?

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Adenomatous polyps may be precursors for cancer. There are three histologic types of adenomatous polyps. Polyps containing > 75% glandular elements are called tubular, those containing > 75% villous elements are termed villous, and those containing > 25% of both glandular and villous elements are tubulovillous.

6. Are some types of polyps more frequently associated with adenocarcinoma?

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Yes. Villous polyps are “bad actors.” Coutsoftides et al. reported 5.6%, 16%, and 41% incidences of adenocarcinoma in tubular, villotubular, and villous adenomas, respectively.

7. What is the relationship between polyp size and risk of adenocarcinoma?

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Polyps < 2 cm have a 2% risk of containing cancer, 2-cm polyps have a 10% risk, and polyps > 2 cm have a cancer risk of 40%. Sixty percent of villous polyps are > 2 cm, and 77% of tubular polyps are < 1 cm at the time of discovery.

8. What are juvenile polyps?

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Polyps that occur in the colon and rectum of infants, children, and adolescents. Histologically, they consist of large mucus-filled glands with lots of connective tissue. The cause of these polyps is unclear. They may represent a response to inflammation, or they may be hamartomas. Juvenile polyps may present as rectal bleeding or as lead points for intussusception. They should be left alone unless they cause trouble, at which point endoscopic polypectomy is sufficient treatment.

9. How are colorectal polyps diagnosed?

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Fecal occult blood test (FOBT) is the most common test in the United States that leads to the discovery of polyps. Sigmoidoscopy and colonoscopy confirm the diagnosis. Colonoscopy has the advantage of being both diagnostic and potentially therapeutic.
KEY POINTS: COLORECTAL POLYPS

1. A polyp is an elevation of the mucosal surface that can occur anywhere in the GI tract.
2. Hyperplastic polyps are small and constitute > 90% of polyps in the colon and rectum.
3. Polyps containing > 75% glandular elements are called tubular, those with > 75% villous elements are termed villous, and those containing > 25% of both glandular and villous elements are called tubulovillous.
4. Fecal occult blood test is the most common test in the United States that leads to the discovery of polyps.

10. What are the risks of colonoscopy?

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Bleeding and perforation. For diagnostic colonoscopy, these risks are extremely low-1.0% and 0.2%, respectively. Both risks are still < 1% for therapeutic colonoscopy. Bleeding usually stops on its own and rarely necessitates laparotomy.

11. How can one determine whether endoscopic polypectomy is adequate treatment?

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In general, if a margin > 1 mm can be obtained, there is no invasion of the muscularis mucosa, and the histologic grade of the lesion is I or II (well to moderately differentiated), the patient should be offered endoscopic polypectomy. Patients with margins < 1 mm, invasion into vessels or lymphatics, and histologic grade III (poorly differentiated) lesions should undergo colon resection, unless comorbid medical conditions contraindicate surgery.

12. What are the screening recommendations to detect polyps?

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There is broad consensus that persons in otherwise good health should undergo periodic screening for colorectal cancer and polyps beginning at age 50 years in average-risk individuals and age 40 years (or 10 years before the index person’s age) in patients with a family history of cancer (excluding genetic colon cancer syndromes discussed below). Colonoscopy every 10 years is the most commonly used strategy, but FOBT with flexible sigmoidoscopy every 5 years for FOBT-negative patients is permissible. All patients who are FOBT positive and those with adenomatous polyps > 5 mm found on sigmoidoscopy should undergo full colonoscopy. To date, FOBT is the only screening test demonstrated in high-quality randomized clinical trials to reduce the risk of death from colorectal cancer. The risk reduction for death is similar to that of mammography (15-33%), depending how the testing is done. The sensitivity and specificity of FOBT is 40% and 96%, respectively, for colorectal polyps. Sigmoidoscopy and colonoscopy are 90% sensitive and 99% specific for polyps. Sigmoidoscopy, however, does not allow for evaluation of the proximal colon, thus lowering the overall effectiveness of this screening technique. Although colonoscopy is highly effective, it must be performed by trained individuals and carries the risk of anesthesia, thus, compromising its value as a screening tool.

13. What are the screening recommendations for patients with known polyps?

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Patients with low risk (one to three tubular adenomas) should have repeat colonoscopy at 5 years. If patients are found to have multiple polyps or high-grade lesions, they should undergo colonoscopy at more frequent intervals (every 2 years). If patients are found to have no new lesions after one screening cycle, screening can be extended to every 5 years.
Malignant polyps should be removed based on the criteria discussed in question 12. Follow-up endoscopy should be performed at 3 months to ensure that no residual tumor is present at the polypectomy site. After this, follow-up should be the same as for multiple adenomatous lesions.

14. Which clinical syndromes are associated with colorectal polyps?

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Familial adenomatous polyposis (FAP) or adenomatous polyposis coli (APC) is inherited as an autosomal dominant trait characterized by multiple adenomatous polyps throughout the GI tract. Diagnosis is made clinically by observing at least 100 adenomatous polyps in the colon; more than 1000 are found in many cases. FAP is caused by the loss of the APC tumor suppressor gene(s) on the long arm of chromosome 5. Multiple family members often are diagnosed with colorectal cancer, generally at a young age. Bleeding, diarrhea, and abdominal pain are common presenting symptoms. FAP is associated with nearly a 100% risk of cancer. FAP is also associated with small bowel, especially periampullary polyps, cancer, and mandibular osteoma.
Gardner syndrome is also associated with loss of the APC gene. Patients have polyposis, as do patients with FAP, but they also have osteomas of the skull, epidermoid cysts, retinal pigmentation abnormalities, and multiple soft tissue tumors.
Turcot syndrome is also associated with APC mutations and is characterized clinically with central nervous system tumors and multiple adenomatous polyps.
Peutz-Jeghers syndrome consists of multiple hamartomatous polyps throughout the alimentary tract. These polyps are associated with cutaneous melanotic spots on the lips, within the oropharynx, and on the dorsum of the fingers and toes. The malignant potential is very low.

15. What is the natural history of APC?

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In a review of more than 1000 cases of adenomatous polyposis coli, the mean age at diagnosis of polyps was 34 years, and the mean age at diagnosis of colorectal cancers was 40 years. The mean age of death was 43 years. It is now recommended that patients with APC undergo colectomy at age 25 years. Patients are also at risk for the late development of foregut adenocarcinoma. Despite prophylactic total colectomy, this group of patients will not have a normal life expectancy.

16. What are the surgical treatment options for APC?

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Treatment options include total proctocolectomy with permanent ileostomy, abdominal colectomy with rectal preservation, abdominal colectomy with ileorectal anastomosis, and ileal pouch-anal anastomosis. In patients in whom the rectum is preserved, yearly endoscopic surveillance is necessary.

17. What role do genetic defects play in the progression of colorectal polyps to adenocarcinoma?

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The progression of adenomatous polyps to colorectal cancer is believed to involve an accumulation of genetic defects via the activation of protooncogenes or the inactivation of tumor suppressor genes. Colon polyps have provided the best available model of genetic mutations in the progression of normal tissue to cancer. Vogelstein and others have provided an elegant description of genetic events demonstrating that polyps accumulate mutations first in the APC and ras oncogenes. Larger, more advanced polyps carry alterations of a tumor suppressor gene on chromosome 18, and carcinomas are associated with inactivation of the tumor suppressor gene TP53 with coincident loss of function of p53 protein.

18. What role do oncogenes play in the development of adenocarcinoma from adenomatous polyps?

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Oncogenes are copies of normal cellular genes that have been activated by mutation. Activating mutations of one allele of an oncogene can disrupt normal cell growth and differentiation and increase the likelihood of neoplastic transformation. The Ki-ras gene is the most commonly mutated oncogene in sporadic colonic neoplasia. Point mutations in the K-ras gene have been observed in approximately 40% of sporadic colorectal adenomas and carcinomas. Analysis of mutations in DNA from cells shed into the stool has been proposed as a potentially useful way to screen for colorectal cancer. In addition, activation of the tyrosine kinase of the c-src gene product pp60s-src is frequent in polyps of high malignant potential; the activity of tyrosine kinase is significantly elevated above the level of primary tumors in liver metastases.

References
WEB SITE
http://www.asge.org
BIBLIOGRAPHY
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