Neoadjuvant Radiotherapy Combined with Transurethral Photoselective Vaporization of Bladder Tumors and Postoperative Adjuvant Radiotherapy and Chemotherapy for T3 Muscle-Invasive Bladder Cancer: A Retrospective Case Series Study.

Objective: To evaluate the efficacy and safety of neoadjuvant radiotherapy combined with transurethral photoselective vaporization of bladder tumors (PVBT), followed by postoperative adjuvant radiotherapy and chemotherapy, in the treatment of T3 muscle-invasive bladder cancer (MIBC). Background: Transurethral resection of bladder tumors combined with radiotherapy and chemotherapy, also known as trimodal therapy (TMT), is the recommended bladder-preserving approach for MIBC and has demonstrated favorable outcomes in T2 MIBC. However, T3 MIBC remains a challenging candidate for TMT due to its relatively poor prognosis. Therefore, optimizing the "triple therapy" strategy for T3 MIBC is essential. Methods: This was a retrospective case series. Patients with T3 MIBC who underwent preoperative neoadjuvant radiotherapy combined with PVBT, followed by postoperative adjuvant radiotherapy and chemotherapy, between January 2018 and December 2020 were included. Tumor response after neoadjuvant radiotherapy, the incidence of PVBT-related complications, and adverse effects of radiotherapy and chemotherapy were assessed. Tumor recurrence and survival outcomes were monitored through outpatient follow-ups and telephone consultations. Risk factors for recurrence were analyzed using statistical methods. Results: A total of 48 patients were included. Four weeks after neoadjuvant radiotherapy, complete response, partial response, stable disease, and disease progression were observed in 3 (6.3%), 23 (47.9%), 20 (41.7%), and 2 (4.2%) patients, respectively. The objective response rate and disease control rate were 54.2% and 95.8%, respectively. Radiation- or chemotherapy-related toxicity occurred in 23 patients (47.9%), all of whom experienced only grade I-II adverse effects, with no grade III-IV toxicity reported. During a follow-up period of 14-58 months, 22 patients (45.83%) experienced recurrence, and 3 patients died due to distant organ metastases. Multi-variate Cox regression analysis identified tumor diameter (≤3.0 cm vs. >3.0 cm) and tumor multiplicity (single vs. multiple) as significant risk factors for recurrence. Conclusions: Preoperative neoadjuvant radiotherapy combined with PVBT, followed by postoperative adjuvant radiotherapy and chemotherapy, is an effective and well-tolerated treatment for T3 MIBC.