Authors: Vielka Fernandez , Arunima Deb , Ekim Kilinc , Francesca Polit , Elias Atri , Celeste Hall , Akshay Bhandari , Monica Recine , Yumna Omarzai

Abstract

Primary seminal vesicle adenocarcinoma (PSVA) is an extremely rare neoplasm whose pathogenesis is currently unknown. Most patients present with non-specific genitourinary symptoms such as hematuria, hematospermia and weak urinary stream, which can delay diagnosis.  As such, it is not uncommon for many of these cases to be diagnosed with already locally advanced disease or distant metastasis.  The differential diagnosis includes metastatic adenocarcinoma from the prostate, bladder, or colon, which are exceedingly more common and must first be excluded.  We present a case of PSVA in a 51-year-old man presenting with hematuria and intermittent hematospermia.  Imaging studies revealed a large, heterogeneous mass expanding the right seminal vesicle.  Initially, a core needle biopsy showed findings suggestive of a mixed epithelial and stromal tumor (MEST). However, histopathologic examination following robotic excision of the mass revealed PSVA. Next-generation sequencing (NGS) revealed a pathogenic variant (c. 146 C>T) in the TERT promoter. The patient received adjuvant chemotherapy. Now, approximately 20 months later, magnetic resonance imaging (MRI) shows a 2.5 cm mass in the right ejaculatory duct at the level of the base of the prostate, concerning for recurrent malignancy. A radical prostatectomy was performed, and microscopic examination revealed recurrent seminal vesicle adenocarcinoma. The patient is currently being followed up for possible adjuvant radiation.

Keywords: Seminal vesicle, adenocarcinoma, genitourinary, neoplasm, urology, pathology.