[Lymph nodes and rectal cancer]. / Ganglions et cancer du rectum.

Nodal invasion is a major prognostic factor of rectal cancer. Lymphatic extension of rectal cancer usually involves the mesorectal nodes then the inferior mesenteric chain but in 14% of patients, particularly with cancer of the lower rectum, metastasic nodes can be observed in the internal or lumboaortic chains situated beyond the usual territory of nodal dissection. On average, 30 nodes are examined on a proctectomy specimen, but with wide interindividual variation. The tumor can be adequately staged if at least 15 nodes are examined with little risk of not recognizing nodal metastasis. Metastatic nodes of rectal cancer are almost always small, more than 90% measuring less than 10 mm and 70% less than 5 mm. The number of invaded nodes and the total number of examined nodes are prognostic factors for survival. Hypofrationated preoperative radiotherapy does not alter the nodal status but a long radiotherapy protocol (45 Gy over 5 weeks) reduces significantly the total number of nodes examined without changing the number of metastasic nodes. Micrometastases (measuring less than 2 mm), identified by immunohistochemistry or gene amplification, can be detected in 25 to 70% of nodes considered metastasis-free at the usual microscopic examination. The prognostic value of these micrometastases remains to be established. The first node draining the tumor (sentinel node), which can be detected rapidly with dye infusion, appears to provide a good picture of the nodal status, the risk of finding an invaded node if the sentinel node is metastasis-free is less than 5%.

[Management of anastomotic fistula following excision of rectal cancer]. / Prise en charge thérapeutique d'une fistule anastomotique après chirurgie rectale pour cancer.

The risk of anastomotic leak after resection of cancers of the mid or low rectum with mesorectal excision is about 10%--the lower the colo-rectal or colo-anal anastomosis, the higher the risk of leak. If the fistula is asymtomatic and the leak is walled off, it is best to defer the closure of the diverting ileostomy for 2-3 months and to proceed only when a radiologic contrast study shows the fistula to have disappeared. More commonly, the anastomotic fistula presents as a pelvic abscess. It is simple and logical to drain the abscess into the digestive tube by enlarging the orifice of the fistula; this can usually be done with a brief general anesthetic. Less commonly, the abscess may present at some distance from the anastomotic leak; this calls for percutaneous drainage. If abscess drainage fails, if pelvic sepsis persists, or if the leak presents from the start as generalized peritonitis, laparotomy is called for in order to lavage the abscess cavity, place effective drains, and perform, if necessary, a diverting stoma upstream. Two strategies are possible: 1) drain placement at the leak site with upstream loop diverting stoma, or 2) takedown of the anastomosis, closure of the distal stump as a Hartmann pouch, and proximal end colostomy in the left lower quadrant. In the first instance, one must be sure the fistula has healed before stoma closure. In the second, the problem is to obtain (at a second stage) sufficient length of well-vascularized proximal colon to make an anastomosis to a short Hartmann pouch or to the anus in a pelvis scarred and inflamed by infection and radiation. A Soave procedure may allow an anastomosis with less risk to peri-rectal innervation and with less blood loss. Two maneuvers which may help to gain length are the Toupet technique for freeing the transverse mesocolon or the Deloyer technique of mobilizing the hepatic flexure. In the face of post-operative pelvic sepsis, an early intervention adapted to the circumstances will increase the chances of healing and reestablishment of intestinal continuity, and may avoid multiple complex interventions with poor functional results including incontinence, urgency, and difficult evacuation.

[Management of familial polyposis coli]. / Prise en charge chirurgicale de la polypose adénomateuse familiale.

Familial Multiple Polyposis Coli is an autosomal dominant hereditary illness characterized by the appearance in childhood of hundreds of colorectal polyps which inexorably undergo malignant transformation. It is accompanied by extracolonic manifestations some of which may also be life-threatening. Total colectomy should not be postponed beyond age 20 except in rare cases of an attenuated form of the disease (AAPC). Subtotal Colectomy with ileorectal anastomosis is a well-tolerated procedure with quite acceptable functional results, but the need for eventual proctectomy is about 30% at 20 years and the risk of rectal cancer is about 10% at 20 years even with close endoscopic surveillance. Total colectomy with ileal pouch-anal anastomosis is therefore the intervention of choice since it eliminates the risk of late rectal carcinoma albeit with more serious morbidity and less good functional results. Desmoid tumors are the leading cause of death in patients who have undergone total colectomy. NSAID's, tamoxifen, and chemotherapy are used preventively and therapeutically; surgical excision is sometimes required. Duodenal adenomas are present in almost 100% of these patients post-colectomy and the risk of duodenal cancer is 200 times higher than in the general population. Endoscopic surveillance of the duodenum is essential and prophylactic duodenal resection should be considered when duodenal polyposis is extensive.