Multidisciplinary management of primary signet-ring cell adenocarcinoma of the urinary bladder and the specific role of adjuvant radiotherapy

Primary signet-ring cell (SRC) of the bladder is an aggressive, extremely uncommon subtype of bladder adenocarcinoma, comprising of <1 % of all primary bladder neoplasms [1]. A report based on analysis of the Surveillance, Epidemiology, and End Results (SEER) Program database found only 103 patients with SRC of the bladder diagnosed between 2001 and 2004, compared to 14,648 patients diagnosed with urothelial carcinoma [2]. The prognosis for patients with SRC is poor, attributed to presentation at advanced stages following asymptomatic progression [3], reported inefficacy of multimodality therapy [4], and possibly a more aggressive underlying biological phenotype [2]. Diagnosis of bladder SRC can be challenging, both as it requires an extensive work-up to rule out more common metastatic adenocarcinomas [5], and comprehensive studies detailing the immunohistochemical profile of these tumors are understandably lacking [6]. Current treatment for this malignancy is often based on experiences gained from single institutional case series. Based on the aggressive natural history of bladder SRCs, treatment often features aggressive surgery in conjunction with chemoand radiotherapy, although standardized recommendations for the use of adjuvant therapy are lacking. In this article, we present a case of locoregionally advanced SRC of the bladder, successfully managed with multimodality therapy. Literature regarding the diagnosis/work-up and management of bladder SRC is reviewed, with a focus on the specific role of adjuvant treatment.