Abstract
When all transurethrally resected material of 53 subsequent patients was microscopically examined, primary adenocarcinoma of the prostate was found in 18 patients and benign disease in 35. Only 9 of the patients with histologically confirmed malignancy of the prostate were clinically diagnosed. The proportion of prostatic chips that contained malignant tissue ranged from 1-96 %. A mathematicl analysis evaluating the probability of including a carcinoma when different numbers of blocks were processes was performed. The analysis showed that when the patient has a clinically malignant diagnosis the probability of 100% is reached by the processing of one block. If the patient has a clinically benign diagnosis, however, the probability of 98% is first reached by the processing of 8 blocks, if such an amount of material is available.