The role of atypical small acinar proliferation in prostate cancer diagnosis: A single center experience

Atypical small acinar proliferation (ASAP) is a condition that describes lesions that are suspicious for malignancy in prostate biopsies but do not contain sufficient histopathological findings to diagnose prostatic adenocarcinoma. This study aims to evaluate the relationship between the clinical and pathological features of cases diagnosed with ASAP between 2010 and 2023 and to evaluate the relationship between this diagnosis and the development of prostate cancer. As a result of the examination of prostate biopsies of 3215 cases in the Department of Pathology of Tokat Gaziosmanpaşa University, 127 (3.95%) cases diagnosed with ASAP were examined. 72 of these cases underwent repeat biopsy, and prostatic adenocarcinoma was detected in 34 (47.2%) of them. The prostate-spesific antigen (PSA) levels of the malignant cases were 30.3 ng/mL on average, which is significantly higher than the benign cases. In immunohistochemical analyses, positive staining patterns were observed with alpha methylacyl CoA racemase (AMACR) and negative staining patterns with high molecular weight cytokeratin (HMWCK) 34βE12 and p63. In patients diagnosed with prostatic adenocarcinoma, 79.4% had a Gleason score of 3+3=6, and 20.6% had a Gleason score of ≥7 (3 cases Gleason score 3+4=7, 1 case Gleason score 4+3=7, 1 case Gleason score 4+4=8, 2 cases Gleason score 4+5=9). Among the treatment options, radical prostatectomy was the most commonly used method. It has been demonstrated that ASAP diagnosis may be an important risk factor for the development of prostate cancer and that close clinical follow-up and repeat biopsy are necessary in these patients. ASAP diagnosis is a clinical condition that should not be neglected and requires careful pathological evaluation and a multidisciplinary approach.