Prophylactic cranial irradiation (PCI) significantly decreases risk of brain metastases in patients with bulky, higher stage small-cell urothelial cancer.

486Background: Patients with bulky, higher-stage small cell urothelial cancer (≥T3b, N+, and/or M+) have a high risk of developing brain metastases. Siefker-Radtke et al reported a 50% risk of brain metastases in this patient population. Therefore, a prospective trial evaluating the potential benefit of PCI was undertaken. Methods: Thirty patients with stage ≥T3b, N+, and/or M+ disease (without brain metastases on MRI) were treated between 12/2008 and 5/2018 with PCI. Patients were treated to a total dose of 30 Gy in 2 Gy fractions over 3 weeks. The patient had baseline brain MRI and mini-mental status exam (MMSE) before the treatment began. After treatment, patients underwent MRI and MMSE every 3-4 months for one year and every 6 months thereafter. If the patients did not have M+ disease at diagnosis, they were also treated with neoadjuvant chemotherapy (usually consisting of cisplatin/etoposide alternating with Adriamycin/ifosfamide), followed by a radical cystectomy. The PCI was either given between th...