THE RESULTS of open perineal biopsy are compared in the present issue of A. M. A. Archives of Surgery1 with those of perineal "punch" biopsy for the purpose of finding which is better for the early diagnosis of unsuspected prostatic carcinoma. This editorial is a word of caution against the indiscriminate application of these experimental results in clinical practice.
We know that about 20% of men over 55 years of age have prostatic carcinoma, since occult neoplasms have been repeatedly found at this rate in routine autopsies. Thus if a large enough biopsy (i. e., total prostatectomy) were done in all men over 55, we would find at least 20% positive specimens. The authors found that only 10.5% of their random extensive open biopsies were positive; in other words, the open method missed half the expected number of cases of cancer. In order to detect all the instances of