Radiation with concurrent radiosensitizing capecitabine tablets and single-dose mitomycin-C for muscle-invasive bladder cancer: a convenient alternative to 5-fluorouracil.

Chemoradiation (CRT) with mitomycin-C (MMC) and 5-fluorouracil (5-FU) has been shown to be superior to radiation alone in patients with muscle-invasive bladder cancer (MIBC). MMC/capecitabine is an effective replacement for 5FU as a radiosensitizer in other malignancies but has not been studied in bladder cancer. We evaluated the outcomes of MIBC patients treated with concurrent radiation and MMC/capecitabine.

MIBC patients treated with CRT (60Gy in 5 weeks with single-dose MMC and capecitabine orally twice daily) between 2014 and 2019 were identified. Acute (<90 days) and late toxicity were registered. Endpoints were clinical complete response (cCR) in the bladder assessed by cystoscopy 3 months after CRT, locoregional disease-free survival (LDFS) and the number of salvage cystectomies.

We analysed 71 cT2-4aN0-2M0 MIBC patients (median age 70 years). Twenty-one (30%) patients received neoadjuvant or induction chemotherapy and 14 (20%) patients underwent a pelvic lymph node dissection prior to CRT. All patients received the full dose of planned radiation. Seven (10%) patients experienced acute grade 3-4 toxicities and 2 (3%) patients experienced late grade 3-4 toxicities. Sixty-eight (96%) patients achieved cCR. Eight (11%) patients had a bladder recurrence, of whom 3 (4%) required salvage cystectomy. Two-year LDFS was 79% (95% CI: 68-88) at a median follow-up of 23 (95% CI: 17-28) months.

Radiation with concurrent MMC/capecitabine is a well-tolerated bladder-sparing treatment. Severe toxicity is infrequent and locoregional tumor control and short-term disease free survival appear similar to previous studies with MMC/5FU.

Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology. 2020 Aug 05 [Epub ahead of print]

Charlotte S Voskuilen, Maaike W van de Kamp, Nannet Schuring, Laura S Mertens, Arjen Noordzij, Floris Pos, Bas W G van Rhijn, Michiel S van der Heijden, Eva E Schaake

Department of Urology, Netherlands Cancer Institute - Antoni van Leeuwenhoek Hospital, Amsterdam, The Netherlands., Department of Urology, Netherlands Cancer Institute - Antoni van Leeuwenhoek Hospital, Amsterdam, The Netherlands; Department of Urology, Spaarne Gasthuis, Hoofddorp, The Netherlands., Department of Urology, Spaarne Gasthuis, Hoofddorp, The Netherlands., Department of Radiation Oncology, Netherlands Cancer Institute - Antoni van Leeuwenhoek Hospital, Amsterdam, The Netherlands., Department of Urology, Netherlands Cancer Institute - Antoni van Leeuwenhoek Hospital, Amsterdam, The Netherlands; Department of Urology, Caritas St. Josef Medical Center, University of Regensburg, Regensburg, Germany., Department of Medical Oncology, Netherlands Cancer Institute - Antoni van Leeuwenhoek Hospital, Amsterdam, The Netherlands., Department of Radiation Oncology, Netherlands Cancer Institute - Antoni van Leeuwenhoek Hospital, Amsterdam, The Netherlands. Electronic address: .