Cytological Diagnosis of Cancer of the Colon and Rectum

Abstract

of Cancer of the Colon and Rectum Tohoku J. exp. Med., 1978, 124(2), 169-176-Results of cytological examination in 120 cases of colon and rectum cancer during the 11-year period ending in 1968 prior to the practical use of fibercolonoscope were first studied.At that time, quite favorable results were obtained in cancer of the lower colon and the rectum, but the results were not so satisfactory in cancer of the right side of the colon. After 1969 when the fibercolonoscope was introduced into the clinical practice, the range of cytological diagnosis under direct vision was at once expanded to the entire colon. Consequently, diagnosis by the cytological method in 140 cases of cancer of the colon and rectum experienced in 6-year period between 1969 and 1974 revealed favorable results.The results of the cytological diagnosis in cancer of the right side of the colon, previously not always favorable, improved markedly after the introduction of the cytological method under direct vision through fibercolonoscope.When early cancer of the colon and rectum is defined as in early gastric cancer, 40 lesions in 36 patients were detected during the past 19 years. The rate of positive result in cases of early cancer obtained by various diagnostic methods was 83% by the cytological method, 78% by biopsy and 91% by polypectomy.In cases in which both biopsy and cytological method were used, one or both frequently gave positive results. These results would indicate the possibility of correct diagnosis in many cases through the combined use of the cytological method and biopsy, without polypectomy. cytological diagnosis; cancer of the colon and rectum Diagnosis of cancer of the colon and rectum is usually made by x-ray examina tion, proctosigmoidoscopy, biopsy and exfoliative cytology. In recent years, a newly developed fibercolonoscope has opened the possibility of direct observation as well as the possibility of cytological study under direct vision through an endoscope in lesions beyond the reach of proctosigmoidoscope.Since 1958 we have made the cytological studies at the Third Department of Internal Medicine, Tohoku University Hospital, for the purpose of detection of cancer of the colon and rectum in its early stage, using various cell sampling methods such as rectal swabbings, modified colon brush method, colonic lavage, and recently, biopsy-smear method under direct vision through the fibercolonoscope (Yamagata et al. 1961;Watanabe 1972). The purpose of this paper is to summarize our experiences and conclusions from these investigations during a 19-year period.

Diagnosis of Early Cancer of the Colon and Rectum

“…When early cancer of the colon and rectum is defined as in early gastric cancer, cancer-containing adenomas comprised the majority (Watanabe et al 1976b;Watanabe 1978). These facts strongly suggest a close relationship between adenoma of the large bowel and cancer of the colon and rectum.…”