Significance of atypical small acinar proliferation and extensive high-grade prostatic intraepithelial neoplasm in clinical practice

INTRODUCTION: Prostate cancer (PCa) is one of the most commonly diagnosed neoplasms in elderly men. The precancerous lesion of PCa is considered a high-grade prostate intraepithelial neoplasm (HG-PIN), while atypical small acinar proliferation (ASAP) is commonly considered as an under-diagnosed cancer. The aim of the study was to establish the impact of ASAP and extensive HG-PIN on pre-biopsy prostate-specific antigen (PSA) levels and the risk of cancer development in subsequent biopseis. MATERIAL AND METHODS: The 1,010 men suspected for PCa were included in the study based on elevated PSA, and/or positive rectal examination. Transrectal ultrasound (TRUS) guided 10 core biopsy was performed. In those with extensive HG-PIN or ASAP on the first biopsy, and/or elevated PSA value, a second biopsy was performed. RESULTS: In the second biopsy, PCa was diagnosed in 6 of 19 patients (31.57%) with extensive HG-PIN, in four of 40 (10%) with BPH, and in 4 of 18 (22.22%) with ASAP. There was a statistically significant difference between the values of PSA in the group of patients with ASAP in comparison to those with benign prostate hyperplasia (BPH) (p = 0.005) as well as in patients with HG-PIN in comparison to BPH (p = 0.02). CONCLUSIONS: A precancerous lesion diagnosed upon biopsy causes a statistically significant increase in the values of PSA in relation to BPH, as well as in the case of ASAP and extensive HG-PIN. The estimate of risk of PCa diagnosis in patients with ASAP and those with extensive HG-PIN in the first biopsy is comparable, which is why there are no reasons for different treatment of patients with the above-mentioned diagnoses. Both should be subjected to urgent second biopsy in around the 4-6 weeks following the initial biopsy.