Evaluation of the mitotic index of human colonic mucosa; results of two different observers.
The mitotic index (M.I.) of the colonic mucosa was evaluated in 67 biopsies and divided into 6 groups. The M.I. was evaluated by one author twice at magnification X 1000 and by the other author once at magnification X 1000 and once at X 400, in order to assess the degree of intra- and interobserver agreement and the most suitable magnification for the evaluation of the M.I. of human colonic mucosa. The results indicate that the mean M.I. of a group of biopsies was similar between the two authors and may therefore be proposed as a valuable estimate of the mitotic activity of a group of patients during scientific investigations, provided that it is evaluated at sufficiently high magnification (X 1000, to our experience). On the contrary, there was only partial agreement (though highly significant) on the M.I. of each individual biopsy between the two authors and between different counts of the same author as well, thus indicating that the M.I. cannot be proposed as an accurate estimate of the mitotic activity of individual patients.
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003106:Colon / Q000166:cytology*; D005260:Female; D006801:Humans; D007413:Intestinal Mucosa / Q000166:cytology*; D008297:Male; D008875:Middle Aged; D008938:Mitosis; D008940:Mitotic Index