Depth of invasion, location, and size of cancer of the anus dictate operative treatment

Abstract

Review of 47 patients with carcinoma of the anus demonstrated that perianal squamous cell carcinoma (16 patients) occurred as a small, in situ/microinvasive lesion more often than did squamous/cloacogenic carcinoma of the anal canal (31 patients). Metastatic lymph node involvement was associated only with anal‐canal lesions (13 of 31 patients). When survival time was examined as a function of tumor extent (depth of invasion, size), however, the prognosis was the same for both types of lesions. Grouping of the anal‐canal lesions into those of the squamous cell and the cloacogenic variety did not demonstrate any differences in outcome. Local excision was successful in each instance for in situ/microinvasive tumors (all were 2 cm or less in diameter), but failed for invasive lesions, even if they were small. Abdominoperineal resection for invasive (26 patients) and for larger microinvasive lesions (three patients) was followed by a 59% five‐ to ten‐year survival. When lesions with lymph node involvement were excluded, the survival rates for perianal (80%) and anal‐canal carcinoma (82%) were similar. The addition of hypogastric lymph node dissection to abdominoperineal resection is indicated for invasive anal‐canal carcinomas; we attribute the long‐term survival of three patients with hypogastric‐node involvement to this extended procedure. The presence of metastatic deposits in inguinal lymph nodes was a grave prognostic sign; all six patients with this finding died within five years. The study concludes that the operative treatment of anal carcinoma can be based on the size and, in particular, the depth of invasion of the lesion and that the histologic type is of limited significance. If local excision is considered, its choice must be guided, for technical reasons, by the location and size of the tumor. Copyright © 1983 American Cancer Society