Comparison between standard and reduced volume radiotherapy in bladder preservation trimodality protocol for muscle-invasive bladder cancer patients

Aim: Our aim is to compare the toxicity, pelvic nodal relapse, and overall survival of whole bladder irradiation only to the standard technique of whole pelvis irradiation followed by bladder boost in patients with muscle-invasive bladder carcinoma undergoing bladder preservation protocol. Material and method: A total of 60 patients with transitional cell carcinoma, stage T2-3, N0, M0 bladder cancer were subjected to maximal transurethral resection bladder tumour (TURB). Then, the patients were randomised into two groups: group I (30 patients) to receive whole pelvis radiotherapy 44 Gy followed by 20 Gy bladder boost. While group II (30 patients) were randomised to receive whole bladder radiotherapy alone for a total dose of 64 Gy. In both groups, concomitant cisplatin and paclitaxel were given weekly throughout the whole course of radiotherapy where conventional 2 Gy/fraction were used. Additionally, four cycles of adjuvant cisplatin and paclitaxel were given after the end of the chemoradiotherapy induction course. Results: The first assessment after the induction chemoradiotherapy showed that complete response was achieved in 73.3% of patients in group I and 76.7% of the patients in group II. After a median follow-up of 2 years, regional relapse occurred in 7.1% of patients in group I and 10.3% in group II. (p = 1). Distant metastases were detected in 17.9% of patient in group I and 13.8% in group II (p = 0.73). The 2-year disease-free survival was 60% in group I and 63.3% in group II (p = 0.79). The whole 2-year overall survival was 75% in group I and 79.3% in group II (p = 0.689). Radiation gastrointestinal (GI) acute toxicity was higher in group I than in group II (p = 0.001), while late GI radiation toxicity was comparable in both groups. Conclusion: Treating the bladder only, without elective pelvic nodal irradiation, did not compromise pelvic control rate, but significantly decreased the acute radiation toxicity.