Hypo-Fractionated Radiotherapy Boost And Concurrent Chemo-Radiotherapy For Patients With Muscle-Invasive Bladder Cancer (MIBC): A Preliminary Report Of The Prospective Phase II Study

Abstract

The primary endpoint was to assess the bladder preservation and the toxicity of bladder. This report presented the acute toxicity profile of this tri-modality treatment (TMT) for patients with MIBC. A total of 38 consecutive patients with cT2-4a bladder cancer underwent TURBT as complete as possible, which was visibly complete in 10 cases. They received hypo-fractionated radiotherapy (RT) to tumor or tumor bed in bladder followed by conventional fractionated RT to pelvis and total bladder, and concurrent infusion Gemcitabine 100 mg/m2 per week. During hypo-fractionated RT, intravesical installation of isovolumetric saline through urinary catheter ensured adequate bladder filling. Patients were reevaluated by the means of cystoscopy and pelvic CT or MRI at 1 month and then every 3 months. Toxicities were assessed using RTOG acute and late gastrointestinal (GI), genitourinary (GU) toxicity criteria. The median age was 72 (35-89). The median follow-up for the entire group was 9 (1-37) months. The two-year overall survival (OS) and cancer specific survival (CSS) was 75% and 90% for all patients, 80% and 100% for N0M0 patients. None patients received salvage cystectomy due to muscle-invasive recurrence in bladder. During radiotherapy, 1 patient (2.6%) complained of Grade 3 GI toxicity, 5 patients (13.2%) complained of Grade 2 GI toxicity. 1 patient (2.6%) reported Grade 3 GU toxicity, 8 patients (21.0%) complained of Grade 2 GU toxicity. 3 patients (20%) complained of urinary moderate pain after radiotherapy and recovered to mild after one month. 1 patient (2.6%) complained of small bladder (<150ml) after 6 months follow-up. None of patients reported urinary incontinence. This combined hypo-fractionated radiation/chemotherapy regimen with TURBT appears to be a well-tolerable and effective treatment strategy for MIBC patients who are not candidates for cystectomy or who wish to avoid cystectomy, and this tri-modality treatment warrants further investigation.