[Nuclear morphology in false negative and negative rectal biopsies (author's transl)]

An typical nuclear structure consisting of a cribriform and condensed chromatin pattern with hyperchromasia, a small nucleolus and a moderately increased nuclear-cytoplasmic ratio was observed in the epithelial cells of the crypts and in the stromal and muscular cells of 51 out of 70 oncologically negative biopsies of the rectal mucosa. The subsequent retrieval of all clinical and histologia data revealed that the 51 cases included 39 of adenocarcinoma of the large intestine either present (15 cases) at a variable distance from the false negative biopsy or removed previously (24 cases), 7 of extra-intestinal malignant tumor (parotid gland, urinary bladder, endometrium, breast, stomach, metastatic, anus) and 5 with benign conditions of the large intestine. Of the remaining 19 cases whose biopsies did not reveal the atypical nuclear structure 16 had benign lesions of the large intestine and nowhere evidence of malignancy, two had an adenocarcinoma of the large bowel (one present and one removed previously) and one a carcinoma of the anus. In the rectal biopsies examined the atypical nuclear structure was detected in 93.9% of the cases with a malignant tumor either present or removed previously and in 19% of the cases with benign conditions. The morphologic evidence indicated that the atypical nuclear structure was compatible with a possible distrubance of the mitotic cycle since the findings were restricted to the generative compartment of rectal epithelium. The results are discussed in connection with their possible practical use as a diagnostic aid in the evaluation and interpretation of false negative and negative rectal biopsies as well as with their possible significance in the biology of tumor-bearing hosts.