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.