Int J Colorect Dis (1991) 6:82-83

Coloreclal Disease 9 Spfinger-Veflag 1991

Endoscopic transanal resection for rectal cancer M. G.W. Kettlewell John Radcliffe Hospital, Oxford, UK Accepted: 21 December 1990

Conventional wisdom states that rectal cancer should be treated radically by anterior resection or abdominoperineal resection of the rectum, with the object of cure, or should this fail then as the best means of palliation [1]. This dictum is, however, seriously flawed and intellectually unsound. Large population-based studies show that the first objective fails for the majority of patients with rectal cancer and there are no good or convincing data on the palliation obtained from radical operations. This is particularly true for patients with locally advanced disease or node metastases where survival is less than 30%. By contrast, early cancers confined to the bowel wall (Dukes' A) have an excellent prognosis with almost all patients surviving 5 years free from cancer. Indeed some patients with small polypoid cancers have been cured endoscopically without resorting to open operation [2, 3]. We must therefore question to what extent radical operation is justified for the majority of patients with advanced lesions or necessary for the few with genuinely early tumours. The prognosis for patients with rectal cancer, in comm o n with most tumours, is multifactorial but a fundamental is the tumour biology manifested by the cancer's propensity to spread locally and to metastasise. The spectrum of behaviour is wide, but for any individual the main measure of biological potential is the clinical stage of the disease at the time of presentation, which correlates closely with survival and the risk of occult hepatic metastasis [4]. Small rectal cancers are seldom systemic, but, at present, there is no reliable method of predicting the growth rate or the potential to metastasise which would enable safe selection of different treatments. Studies of tumour genome and surface proteins offer some hope of predicting tumour behaviour more accurately than degree of differentiation [5]. Lest I appear too deterministic; it must be recognised that surgical technique has a material effect upon prognosis. Postoperative mortality and anastomotic leakage vary and the risk of local recurrence may vary fourfold among a large number of surgeons [6]. However the role of surgical technique, and in particular the necessity for

radical operations, may be confused by the inherent selection bias of personal series with a preponderance of early lesions [7]. Furthermore, the concept of cure is not simple, for cure and palliation are part of the same continuum and not discrete objectives. For any given patient the prospects are the integral of the tumour biology and the patient's age and concurrent illness. Postoperative mortality increases progressively over the age of 70 years and the potential gains diminish. Rigid adherence to a single major means of tumour control, under these circumstances, denies the complexity of the clinical condition and attempts to reduce it to absurd simplicity, somewhat akin to playing golf with only one club and a driver at that! There is therefore a need to select treatment for each patient from a variety of methods, a concept now well established in the management of breast cancer. Because rectal cancers are potentially accessible per anum a number of techniques for local treatment have been proposed and yet there are suprisingly few large series reporting the results of such methods [8]. Local recurrence is more c o m m o n after local removal and recurrence is usually considered to be a treatment failure, which may not be correct in some patients [9]. Who then is suitable for local "curative" therapy for rectal cancer and by what technique is this best achieved? First and foremost, patients who are old and infirm, and who have a limited life expectancy should be considered for local therapy. F o r these patients the burden and risks of major surgery outweigh the risks of failure to control or cure the disease, as with blind or handicapped patients who cannot cope with a stoma, patients with weakened sphincters unable to contain the urgency which follows a low anterior resection or coloanal anastomosis, or patients who refuse major surgery or a permanent stoma. For such patients size and situation of the cancer is not crucially important. Any patient with a small, well differentiated, Dukes' A or early B cancer should be offered local removal. Here endoluminal ultrasound may be important in selection and staging the tumour accurately

83 and monitoring the postoperative course pending reliable biological indicators of t u m o u r behaviour [10]. Full thickness disc excision through the dilated anus with suture of the defect is the most c o m m o n method of local removal. The method has the attraction of providing a complete specimen, but requires wide dilatation of the aged anus, encourages close dissection and is often difficult for larger and more proximal tumours. In my opinion endoscopic transanal resection using a wide bore resectoscope with continuous glycine irrigation is the best method for local removal of rectal tumours [11]. Vision is good, the "target" is magnified, haemostasis is easy and removal is both easy and accurate which encourages a generous resection margin. Muscle layers are readily identified and the cancer can be pursued out into the perirectal fat when palliation is the principal objective. The defect in the bowel wall does not need closure and in only one case in over 100 has a fistula occurred, although a transient pyrexia is common. The sphincters are not dilated and so incontinence has not been a problem. Resection above the peritoneal reflection clearly runs the risk of intraperitoneal perforation and is therefore reserved for patients receiving palliation only or patients with particularly small superficial cancers. Resection has the added attraction of being readily repeatable in the same way that patients with bladder neoplasms can have repeated trans-urethral resection with little constitutional upset. Repeated resection m a y be necessary to eradicate tumours, exemplified by six patients (including one octogenarian who had a local reccurrence after an anterior resection elsewhere) who required a median of four resections (range 2 - 8 ) over 6 months to 3 years, and who have subsequently been free from local recurrence for a median of 3 years (range 2 - 8). It is possible that the scarring induced by the thermal injury m a y inhibit tumours with a lower capacity for angiogenesis. In a similar number of patients repeated endoscopic transanal resection (ETAR) has completely failed to provide local control and salvage resection has been necessary to provide modest and t e m p o r a r y palliation. Palliation is the main indication for E T A R where most tumours can be controlled for the patient's residual

life, but in about 50 patients with "curable" cancers the crude 1 year survival is 80%. The precise role for E T A R in this group of selected patients will have to await detailed analysis of an adequate cohort of patients to compare with the results of more conventional radical removal in similar elderly patients. Nevertheless, E T A R is a useful technique which compares favourably with peranal excision, electrodesiccation and laser therapy, all of which I have used.

References 1. Anon (1990) Endoscopic transanal resection. Lancet 336:411412 2. Wolff WI, Shinya H (1975) Definitive treatment of malignant polyps of the colon. Ann Surg 182:516-523 3. Sugihara K, Muto T, Morioka Y (1989) Management of patients with invasive carcinoma removed by colonoscopic polypectomy. Dis Colon Rectum 32:829-834 4. Finlay IG; McArdle CS (1986) Occult hepatic metastases in colorectal carcinoma. Br J Surg 73:732-735 5. Workman P (1990) The cell membrane and cell signals: New targets for novel anticancer drugs. Annals of Oncology 1:100110 6. Phillips RKS, Hittinger R, Blesovsky L, Fry S, Fielding LP (1984) Local recurrence following curative surgery for large bowel cancer. 1. The overall picture. Br J Surg 71:12-16 7. Karanja ND, Schache DJ, North WRS, Heald RJ (1990) 'Close shave' in anterior resection. Br J Surg 77:510-512 8. Biggers OR, Beart RW, Ilstrup DM (1986) Local excision of rectal cancer. Dis Colon Rectum 29:374-377 9. Killingback MJ (1985) Indications for local excision of rectal cancer. Br J Surg 72 [Suppl]: 54 56 10. Beynon J, Mortensen NJ, Rigby HS (1988) Rectal endosonography: a new technique for the preoperative staging of rectal carcinoma. Eur J Surg Oncol 14:297-309 11. Berry AR, Sourer RG, Campbell WB, Mortensen NJMcC, Kettlewell MGW (1990) Endoscopic transanal resection of rectal turnouts - a preliminary report of its use. Br J Surg 77:134-137 M. G. W. Kettlewell John Radcliffe Hospital Headington Oxford OX3 9DU UK

Endoscopic transanal resection for rectal cancer.

Int J Colorect Dis (1991) 6:82-83 Coloreclal Disease 9 Spfinger-Veflag 1991 Endoscopic transanal resection for rectal cancer M. G.W. Kettlewell John...
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