Objective: To study the evolution of 64 patients initially diagnosed with ASAP (atypical small acinar proliferation).
Material and methods: Between 1998 and the end of 2003, 64 patients were diagnosed at our centre with ASAP.
Results: The mean age of the patients assessed was 69 years (SD 6.4 years), the median prostate-specific antigen (PSA) level was 7.1 ng/ml (range 2-39 ng/ml) and 25% of the patients had a suspicious rectal examination. These 64 patients were subjected to re-biopsy. At re-biopsy, we diagnosed 27 patients (42%) with prostate adenocarcinoma. We classified patients into two groups depending on whether they did (n=27) or did not (n=37) have tumours. There were no significant differences in median PSA level between the two groups. The rectal examination was suspicious in 14% of patients without tumours and in 39% with tumours. Radical prostatectomy was applied to 20/28 patients (71%) diagnosed with prostate cancer. In these 20 patients, the median tumour volume was 0.4 cm3 (range 0.1-3.2 cm3) and 44% of the tumours were significant. The 37 patients with an unsuspicious histology were subjected to follow-up for a median of 12 months (range 1-30 months). The median PSA level in these patients was 5.7 ng/ml (range 0.8-28 ng/ml). A third biopsy was performed in three of these patients in view of an elevated PSA level, and one result was positive.
Conclusions: In our experience, a pathological result of ASAP is associated with a definitive diagnosis of prostate cancer in 42% of cases. Moreover, a significant cancer was found in 44% of patients subjected to radical prostatectomy. We therefore systematically perform repeat biopsies on all patients with a histological result of ASAP.