Diagnosis and Management of Synchronous Prostate and Rectal Cancer in a Patient

The management of the synchronous occurrence of prostate and rectal cancer presents a challenge due to their anatomic proximity. Considering the high morbidity and mortality of malignancies individually, well-targeted treatment planning is required for optimal survival outcomes; however, management strategies have not been standardized. We describe the diagnosis and treatment of synchronous prostate and rectal cancer in a single patient. An Epic chart review of a 70-year-old man with synchronous prostate and rectal cancer was completed. The patient presented with urinary frequency, weak urinary stream, and nocturia. Magnetic resonance imaging (MRI) and transrectal biopsy confirmed intermediate-risk, stage IIC prostate adenocarcinoma. Concurrently, findings suspicious for malignancy were identified on screening colonoscopy. MRI and pathology confirmed stage IIIB colonic adenocarcinoma. Initial treatment for the prostate cancer was begun with leuprolide and bicalutamide. Subsequently, the patient was prescribed volumetric modulated arc therapy (VMAT) to the rectum, prostate, and lymph nodes; followed by the rectum and prostate; and finally the prostate. The patient received concurrent capecitabine. When treating synchronous malignancies, an integrated approach is necessary to minimize the length of intervention and adverse events. Compared to the serial treatment of rectal and prostate cancer, concurrent treatment with the expansion of the target volume has demonstrated decreased risk of wound complications and comparable disease-free survival. Further long-term follow-up and monitoring are needed to establish standard management strategies for synchronous prostate and rectal cancer.