European Journal of Biomedical and Pharmaceutical Sciences

BENIGN MIMICKERS OF PROSTATIC CARCINOMA: INCIDENCE, CORRELATION WITH PSA LEVELS AND THE DIAGNOSTIC DILEMMAS

*Dr. Mahsheena K. M., Dr. Ira Baradwaj and Dr. Karpagam Janardhan

ABSTRACT

Background: There are several benign proliferations and normal histoanatomical structures of prostate which mimic malignancy and their awareness is essential to avoid diagnostic pitfalls. Establishing, or ruling out, the diagnosis of carcinoma of prostate has been a well-known challenge for pathologists for many years. Aim: To assess the morphological spectrum of benign mimickers of prostatic carcinoma, their incidence and correlations with serum PSA levels. Materials and Methods: This study included a total of 180 cases of prostatic biopsies. All the lesions were graded into non-neoplastic and neoplastic lesions. Cases with foci where malignancy was questioned and which upon expert review the entire case was determined to be benign were included as benign mimickers of prostatic carcinoma. Immunohistochemical (IHC) were used in suspicious and atypical cases for a confirmative diagnosis. The histological features were correlated with serum PSA levels. Results: Non-neoplastic lesions were common in this study with 39.4% associated with benign mimickers. 71 cases(39.4%) formed the group benign mimickers of prostatic carcinoma which included basal cell hyperplasia (21.6%), small acinar proliferation (8.89%), atrophy (6.1%), adenosis (3.3%), granulomatous prostatitis (1.67%) and inflammatory atypia (0.6%). IHC was essential in 24 (13.3%) cases for correct diagnosis. Majority of the benign mimickers of prostate had higher PSA levels >4ng/ml (81.6%). Basal cell hyperplasia and Small acinar proliferation had PSA level >10ng/ml. CONCLUSION: Basal cell hyperplasia and small acinar proliferation are the most common benign changes causing diagnostic difficulty. Careful examination of H&E sections usually suffices to diagnose these benign mimickers. However in 13.3% of cases IHC was essential for a conclusive diagnosis. Using a panel of immunostains including AMACR, 34βE12 and p63 (positive AMACR immunostaining along with negative basal cell markers) is recommended in the differentiation of prostatic cancer and benign mimickers.

Keywords: Benign mimickers, Prostatic carcinoma, PSA, Basal cell hyperplasia, Small acinar proliferation.