Squamous-Cell Carcinoma of the Anus and Anal Canal: An Analysis of 55 Cases

Abstract

The analysis is of 55 cases admitted into St. Mark's Hospital from 1922 to 1940. The incidence was 3.35% of all cases of cancer of the rectum, anal canal and anus admitted during this period. Sex distribution—27 males and 28 females. The average age (61.7 years) is higher than that of columnar-cell carcinoma of the rectum (57.4 years). Histology.—The cases have been graded into three grades of malignancy—low grade, medium grade, and high grade. Low grade squamous carcinoma is twice as frequent in men as in women, and generally originates at the anal margin. Medium grade squamous carcinoma is equally distributed between men and women; it may arise at the anus or in the anal canal. High grade squamous carcinoma is much more common in the female sex and is almost entirely limited to the anal canal. Quadrant affected—about one-third of the anal margin growths and one-half of the anal canal growths were situated anteriorly. Differential diagnosis from simple papilloma, simple ulcer, chronic inflammation, tuberculous ulcer, tuberculide, primary chancre, amœbic ulcer, basal-cell carcinoma, columnar-cell carcinoma. Biopsy and grading essential before treatment is decided upon. The results of treatment in the three grades of malignancy are described. The best results were obtained in the early low-grade cases treated by interstitial radium needling. In the medium and high grades only three five-year survivals can be reported and these followed excision of the rectum. The management of the inguinal glands is discussed and the importance of a very close post-operative supervision emphasized. Squamous carcinoma of the anal canal may cause lymphatic metastases in the superior hæmorrhoidal glands; there have been four such cases in this series. Diathermy perineal excision is indicated in these cases. © 1941, The Royal Society of Medicine. All rights reserved.