Patterns of chemotherapy use in patients with muscle-invasive bladder cancer at a single tertiary institution in Australia.

Abstract

Introduction and objectives: Although randomised studies demonstrate a survival benefit with neoadjuvant chemotherapy (NAC) prior to cystectomy (RC) in muscle invasive bladder cancer (MIBC), concerns remain about delay in surgical treatment, chemotherapy toxicity and progression in nonresponders. There is no Australian data on patterns of NAC use prior to cystectomy. Our aim was to evaluate the practices and patterns of NAC and adjuvant chemotherapy (AC) use for MIBC in a single tertiary centre in Australia. Method(s): Patients who underwent a RC at our centre between 2011 and 2021 were retrospectively identified using Medicare Benefits schedule codes. Patients who had a histologic diagnosis of >= pT2 urothelial carcinoma at transurethral resection of bladder tumour (TURBT) were identified. Patient, chemotherapy and tumor data were collected and Kaplan Meier survival analyses performed. Result(s): Of a total of 120 patients, 70 had a RC for pT2+ bladder cancer. Of these patients, six (8.6%) patients received NAC prior to RC and 20 (28.6%) received AC and two (2.9%) received adjuvant radiotherapy. 19 patients (27.1%) developed metastases and 20 (28.6%) died at a median follow-up of 20.8 (Interquartile range, IQR 7.3- 53.9) months. In those who received NAC, the median time from diagnosis to RC was 3.8 months (IQR 2.1 -4.6). Three patients were treated with ddMVAC, two with Gemcitabine and Cisplatin and one with Cisplatin and radiotherapy. Of these, four (66.7%) had downstaging to pT1 disease at RC, one (16.7%) developed metastases and two (33%) died on follow-up. The median time from cystectomy to AC was 1.6 months (IQR 1.4-2.2). Gemcitabine and Cisplatin were most frequently used (55%) as AC followed by ddMVAC in the 20 patients. 26 patients out of 46 (56.5%) who were eligible for AC did not receive chemotherapy due to patients being unfit (10.9%), patients declining treatment (10.9%), deemed inappropriate for AC (due to timing and histopathological variant) (6.5%), death prior to commencement of AC (4.3%) and unknown reasons (17.4%). Of the 20 patients who received AC, five (25%) developed metastases and six (30%) died following AC. There was no difference in progression free survival or overall survival between those who received NAC and AC. Conclusion(s): Majority of patients undergoing RC for MIBC received AC compared to NAC, reflecting realworld practice. While AC allows for better selection of patients for chemotherapy post RC, a large proportion may not ultimately receive adjuvant therapy. Further studies on the determinants of real-world selection for NAC could possibly deliver additional evidence in the patterns of chemotherapy usage.