Favorable toxicity of chemoradiation for muscle-invasive bladder cancer in elderly, frail patients.
Authors: Assaf Moore, Zhigang Zhang, Bernard H. Bochner, Timothy F. Donahue, Jonathan E. Rosenberg, Gopa Iyer, Samuel Aaron Funt, Dean F. Bajorin, Min Yuen Teo, David Henry Aggen, Daniel Gorovets, David Guttmann, Michael J. Zelefsky, Marisa Kollmeier
Journal: Journal of Clinical Oncology (2022)

507 Background: Chemoradiation (CRT) for bladder cancer provides comparable outcomes to radical cystectomy; however, concerns regarding toxicity, particularly in elderly, frail patients limit its utilization. Methods: We identified 150 consecutive patients who underwent definitive CRT for T1-4N0M0 bladder cancer at Memorial Sloan Kettering Cancer Center between 2005 and 2020. Most were men (71.3%), elderly (median age, 77.5 years), had high Charlson Comorbidity Index (CCMI) score (median, 7), were nonsurgical candidates (65.3%), Stage T2 (75.3%) and had a macroscopically complete TURBT (65%). 24% of patients received neoadjuvant platinum-based chemotherapy. Concurrent gemcitabine was used in 98.7%. 116 (77.3%) patients underwent 45Gy to the pelvic lymphatics/whole bladder followed by bladder boost (median total dose, 66.6 Gy) and 34 patients (22.7%) received 55 Gy in 20 fractions to the whole bladder/ urethra only. Fiducial markers for image-guidance were used in 55% (83/150) of cases. Patients were followed post-treatment with toxicity assessment, cytology/cystoscopy and imaging every 3 months year 1, every 6 months for years 2-3 and annually thereafter. Acute (≤3 months) and late ( &gt; = 3 months) gastrointestinal (GI) and genitourinary (GU) toxicities were assessed according to CTCAE v4.0. Complete response (CR) was defined as no evidence of disease at 3-month follow up. Survival outcomes were estimated using the Kaplan-Meier method. Median follow up was 31 months (range, 0-155 months). Results: The majority (94%) completed the prescribed course of radiation. Acute grade 3 GU and GI toxicities occurred in 2% and 5.3% of patients, respectively. No acute grade 4 toxicity was recorded. The most common GU and GI toxicities were radiation cystitis and diarrhea. Late grade ≥2 GU and GI toxicity occurred in 11.2% and 0.7% or cases, respectively. One late grade 4 GI toxicity was recorded (small bowel obstruction 7 months after completion of CRT). 80% (n = 120) of patients achieved a CR. Of complete responders, 30% (36/120) developed recurrent disease at a median time of 13.8 months (range, 3.2- 90.4). Among them, local only vs regional/distant recurrence rates were 72.2% and 27.8%, respectively. Of entire cohort, 40% of patients were alive and 31% had died with no evidence of disease at last follow up. While the estimated 5-year OS was 48% (95% CI, 39%, 59%), the estimated 5-year disease-specific mortality rate was 31% (95% CI, 24%, 40%). On univariate analysis, younger age (p &lt; 0.001), receipt of neoadjuvant chemotherapy (p = 0.006) and surgical candidacy (p = 0.041) were predictive of improved OS. On multivariate analysis, only younger age was significant (p = 0.006). Conclusions: CRT had a favorable toxicity profile and encouraging cancer control outcomes in this unselected, mostly elderly and frail patient cohort.