Cytological atypia in the prostate gland: frequency, distribution and possible relevance to carcinoma.

Frequency and distribution of atypical prostatic hyperplasia were assessed in 51 total prostatectomy specimens for cancer and the data were compared to similar data obtained from analysis of 51 autopsy specimens. Enlargement of columnar cell nuclei in conjunction with preservation of basal cells was chosen as the only criterion for atypia. Depending on the degree of nuclear enlargement, atypia was divided into mild and severe degrees. The evaluation of nuclear atypia was applied to areas of carcinoma as well as to atypical prostatic hyperplasia. There were 3 major findings. 1) Atypical prostatic hyperplasia was found more frequently in prostatectomy specimens (48 of 51 cases) than in autopsy specimens (14 of 37 cases after exclusion of cancer-associated cases) and the difference was significant (p less than 0.001). In addition, atypical prostatic hyperplasia found in prostatectomy specimens was more frequently of severe degree than that in the autopsy specimens (42 of 48 versus 3 of 14 cases, p less than 0.001). 2) The distribution of atypical prostatic hyperplasia and carcinoma in prostatectomy specimens was similar. 3) In a majority of prostatectomy specimens atypical prostatic hyperplasia, when found, was located at sites separate from carcinoma as well as in contiguous areas. Based on these data it is suggested that the presence of a severe degree of nuclear atypia in specimens removed for benign conditions or in prostatic needle biopsies may signify an increased incidence of coexisting carcinoma elsewhere in the prostate or of carcinoma developing in the future. Close followup of these patients may be indicated.