Hypofractionated Radiation Therapy (Hypo-RT) for the Treatment of Localized Bladder Cancer

Various radiotherapeutic regimens are used in the treatment of bladder cancer.

We aimed to evaluate early toxicity and outcomes associated with hypofractionated radiation therapy (Hypo-RT), 55Gy in 20 fractions.

We identified 40 patients who received definitive Hypo-RT for localized bladder cancer. Most patients were men (62.5%), elderly (median age 82), had high Charlson Comorbidity Index score (median 7, range 4-9) and were nonsurgical candidates (80%). Sixty-eight percent had a macroscopically complete transurethral resection of bladder tumor (TURBT) and 33 patients (82.5%) received concurrent chemotherapy. Acute (< =3mo) and late (>3mo) toxicities were assessed according to CTCAE v4.0. Survival outcomes were estimated using the Kaplan-Meier method. Median follow up after Hypo-RT was 32 months (95% CI: 28-49 months).

Overall rates of acute grade 2 genitourinary (GU) and gastrointestinal (GI) toxicities were 40% each, most commonly urinary frequency and diarrhea. Two cases of acute grade 3 GU/GI toxicity occurred. Late grade 2+ toxicity occurred in 3 patients (7.5%): 2 grade 2 GU and 1 grade 3 GI. Seventy-seven percent achieved a complete response (CR). Six patients (20%) developed disease recurrence at a median time of 9.1 months. The estimated 2-year DFS and 2-year DSS rate were 59% (95% CI, 45-78%) and 78% (95% CI, 65-93%), respectively. Receipt of concurrent chemotherapy (p = 0.003) and achieving a CR (p = 0.018) were univariably associated with improved DSS. Tis component was associated with worse DSS (p = 0.015).

Hypo-RT had a favorable toxicity profile and encouraging cancer control outcomes in this mostly elderly and frail patient cohort.