In muscle-invasive (“growing into the muscle layer”) bladder cancer (non-muscle-invasive bladder cancer, nMIBC) (cT2-4), radiotherapy can be used in patients in whom tumor removal by radical cystectomy (removal of the urinary bladder) is not possible. A transurethral resection (TUR) of the tumor (removal of the tumor through the urethra) should then be performed before radiotherapy.
After R1 resection (macroscopically, the tumor has been removed; however, histopathology shows smaller portions of tumor in the resection margin), postoperative radiotherapy may be considered.
Radiochemotherapy (RCTX)
For muscle-invasive bladder carcinoma, a combination of radiotherapy and chemotherapy can be performed in addition to radiotherapy. However, this is indicated only in patients who are not candidates for radical cystectomy. Note: In a case-control study of patients who had muscle-invasive urothelial carcinoma of the bladder (T2-4aN0M0), radiochemotherapy (RCTX) yielded comparable survival results to cystectomy.
Elderly patients with metastatic muscle-invasive bladder cancer also have high benefit from chemotherapy within 30 days of radiotherapy (radiochemotherapy, RCTX):
Probability of dying was 26% lower in the combination therapy group than in patients receiving radiotherapy alone (hazard ratio [HR]: 0.74; 95% confidence interval between 0.65 and 0.84; p < 0.0001)
After two years, 56% of patients in the combination therapy group were still alive (vs. radiation therapy alone, 42%)
In the current guideline program, the consensus-based recommendation (without age information) for muscle-invasive urothelial carcinoma is that simultaneous radiochemotherapy (RCTX) should be performed “as part of a bladder-preserving approach with curative intent.”
The American Society of Clinical Oncology (ASCO) and the European Association of Urology note that explicitly in patients with muscle-invasive bladder cancer, organ-preserving treatment should be emphasized as an important option as an alternative to radical surgery with urinary bladder loss. Some patients particularly benefit from this approach.
With respect to the rate of locoregional recurrence (recurrence of disease), radiochemotherapy (RCTX) is significantly superior to radiotherapy alone in invasive urothelial carcinoma. However, this is not associated with a significant survival benefit.
