Synchronous Dual Primary Malignancy of the Prostate: A Rare Entity with Management Dilemma and Review of Literature

Abstract Dual synchronous primary squamous cell carcinoma and adenocarcinoma of the prostate is a rare subtype of prostate cancer. Here, we present a case of prostate adenocarcinoma and squamous cell carcinoma occurring concurrently without any prior hormonal or radiation therapy. A 62-year-old gentleman presented with moderate lower urinary tract symptoms for 6 months. On evaluation, he was found to have prostatomegaly with an elevated prostate-specific antigen (PSA) of 10.8 mg/dL; Multiparametric magnetic resonance imaging prostate revealed a lesion in the right posterosuperior peripheral zone with involvement of the right seminal vesicle. Prostate biopsy revealed prostatic adenocarcinoma, Gleason score (4 + 4), Grade group 4 with squamous cell cancer involving 50% of the total core area. The acinar component exhibited alpha methyl acyl CoA racemase immunopositivity but was negative for CK5/6, GATA3, and P40. The squamous component exhibited strong immunopositivity for CK5/6, GATA3, and P40. He received three monthly injections of Leuprolide 22.5 mg and radical radiotherapy of 60 Gy in 20 fractions over 4 weeks. On follow-up, his nadir PSA is 0.1 ng/mL, and he is doing well in 12 months of follow-up.