Objective: This work attempts to determine the importance of small foci of prostatic cancer in random multifocal needle biopsy specimens. Method: 64 patients with a microscopic focus confined to a single core specimen (which defined as tumor less than 1 mm with a Gleason score of 6 or less) were identified from a retrospective review of 1206 needle biopsies of the prostate. Twelve of these 64 subsequently under went radical retropubic prostatectomy at our centre. Clinically significant tumors were defined as those with volume greater than 0.5 cc. Results: Average tumor volume was 0,9±0,6 cc (range 0,068-2,9 cc). In 41,66 % (5) of the cases was less 0,5 cc (range 0,068-0,458 cc, mean volume -0,22±0,15 cc). There was 1 (8,4 %) of patient with extraprostatic extension. Conclusion: Our data have shown high frequency of revealing insignificant tumours (mean 42±28 %; Р=0,95). However, about 60 % of patients had clinically significant tumors warranting definitive therapy. The smallest focus of cancer on needle biopsy is not a guarantee of a clinically insignificant tumor.