Selective bladder‐sparing protocol consisting of induction low‐dose chemoradiotherapy plus partial cystectomy with pelvic lymph node dissection against muscle‐invasive bladder cancer: oncological outcomes of the initial 46 patients

Abstract

To evaluate oncological outcomes of muscle-invasive bladder cancer (MIBC) patients who were treated with a selective bladder-sparing protocol consisting of induction low-dose chemoradiotherapy (LCRT) plus partial cystectomy (PC) with pelvic lymph node dissection. From 1997-2010, 183 consecutive patients with cT2-4aN0M0 bladder cancer (median age 70 years, women/men = 46/137, T2/3/4a = 100/69/14) underwent debulking transurethral resection followed by LCRT (radiation at 40 Gy to the small pelvis concurrently with two cycles of i.v. cisplatin at 20mg/day for 5 days). Criteria for PC include: (i) essentially solitary MIBC or intravesically circumscribed tumours (≈25% or less of the bladder in area, excluding the bladder neck and trigone); (ii) no involvement of bladder neck or trigone; and (iii) clinically, no residual disease or minimal amounts of non-invasive disease in the original MIBC site after LCRT; otherwise, radical cystectomy (RC) is recommended. Primary and secondary endpoints were cancer-specific survival (CSS) and intravesical MIBC recurrence-free survival (MRFS) for bladder-preserved patients, respectively. Of the 183 patients, 87 (48%) achieved a clinical complete response after LCRT and 65 (36%) met the PC criteria; 46 (25%) patients actually underwent PC, 86 (47%) had RC, and the remaining 51 (28%) had neither PC, nor RC. Histological examination of the 46 PC specimens showed residual muscle-invasive disease in three (7%). Overall, 5-year overall survival and CSS rates were 64% and 71%, respectively (median follow-up for survivors of 45 months). In the 46 PC patients, neither MIBC, nor pelvic recurrence was observed; 5-year CSS and MRFS rates were both 100%. In 13 non-PC patients who achieved a complete response after LCRT and who met PC criteria but declined PC, 5-year CSS and MRFS rates were 74% and 81%, respectively; CSS and MRFS were significantly better in the PC group than in the non-PC group (P= 0.025 and 0.002, respectively). In the current selective bladder-sparing protocol, one-third of MIBC patients met the PC criteria; when patients from this group underwent PC with pelvic lymph node dissection, their oncological outcomes were excellent. Consolidative PC potentially reduces MIBC recurrence in the preserved bladder, eventually improving survival in properly selected MIBC patients.