Significance of focal proliferative atrophy lesions in prostate biopsy cores that test negative for prostate carcinoma

OBJECTIVES: To evaluate the prevalence and short-term follow-up of focal proliferative atrophy lesions, either with or without the presence of inflammation (PIA/PA), and its correlation with the PSA levels, focusing on the prostate biopsy cores that test negative for prostate adenocarcinoma (PCa). METHODS: Five hundred fifty consecutive patients who had undergone a transrectal ultrasound-guided transperineal prostate biopsy were evaluated retrospectively for the presence and follow-up of focal proliferative atrophy lesions. PIA/PA were defined according to De Marzo. The prevalence of atrophy in PCa and negative biopsy cores was compared by means of chi(2). After logarithmic transformations of the PSA values, t-test and ANOVA were applied for the comparison of the means. Incidence of newly diagnosed PCa during follow-up (mean 33.7 months) in patients with or without focal proliferative atrophy was compared by means of chi(2). RESULTS: A focal atrophic lesion resulted in 161/339 negative biopsies. PIA was observed in 93/161 patients (57.8%), while PA was observed in the remaining 68/161 (42.2%). Among the negative biopsy cases, the difference in PSA values were not statistically significant according to the presence or absence of atrophy (P = 0.120). The group of negative biopsies with PIA was similar in terms of PSA characteristics with the benign (PA P = 0.738; non-atrophy P = 0.342), and cancer subgroups (P = 0.094); 245/339 (72.3%) patients were successfully followed-up. Biopsy was repeated in 24/71 (33.8%) patients with PIA, in 14/50 (28%) with PA and in 27/124 (21.7%) with no atrophy lesions at initial biopsy. The incidence of newly diagnosed PCa in the 3 groups was not statistically different (chi(2), P = 0.81). CONCLUSIONS: Focal proliferative atrophy lesions are a common finding in biopsy specimens negative for PCa. Patients with negative biopsy associated with PIA presented similar PSA characteristics as patients with biopsy-proven PCa. However, the incidence of PCa at short-term follow-up did not differ significantly between patients with PIA, PA, or no atrophic lesions at initial biopsy. Based on our findings, early repeat biopsy does not seem to be necessary after an initial diagnosis of PIA/PA, although a longer follow-up is mandatory for definitive conclusions.