Three versus four cycles of neoadjuvant chemotherapy for muscle-invasive bladder cancer: a systematic review and meta-analysis

The optimal cycle of neoadjuvant chemotherapy (NAC) for muscle-invasive bladder cancer (MIBC) remains controversial. This study aimed to compare the efficacy of three and four cycles of NAC in the treatment of MIBC through a systematic review and meta-analysis of the literature. Relevant studies were systematically collected and reviewed in PubMed, Medline, Embase, Web of Science Databases, and the Cochrane Library. Relative ratios (RRs), Hazard ratios (HRs) and their 95% confidence intervals (CIs) were used to estimate outcome measures. Studies comparing the pathological response and prognosis of three versus four cycles of NAC for MIBC were included. Five studies were included in this meta-analysis, including 2190 patients, of whom 1016 underwent three cycles of NAC and 1174 underwent four cycles of NAC. All studies were retrospective cohort studies. We found that 4 cycles of NAC had significantly better cancer-specific survival than 3 cycles (HR = 1.31, 95%CI,1.03–1.67, <i>p</i> = 0.029). There was no significant difference in overall survival between patients who received 3 and 4 cycles of chemotherapy (HR = 1.18, 95%CI = 0.83–1.69, <i>p</i> = 0.345). Similarly, no significant difference was observed in pathological objective response (RR = 0.95, 95%CI= 0.81–1.11, <i>p</i> = 0.515) and complete response rates (RR = 0.87, 95%CI = 0.69–1.11, <i>p</i> = 0.256) in MIBC after 3 or 4 cycles of NAC. Three and four cycles of NAC had similar pathological responses and prognosis for MIBC, although the cancer-specific survival rate of four cycles was better than that of three cycles. The pathological response rate and overall survival of three and four cycles of neoadjuvant chemotherapy for muscle-invasive bladder cancer were similar.Four cycles of neoadjuvant chemotherapy may improve the cancer-specific survival of patients with muscle-invasive bladder cancerIt is reasonable and feasible for clinicians to use three or four cycles of neoadjuvant chemotherapy. The pathological response rate and overall survival of three and four cycles of neoadjuvant chemotherapy for muscle-invasive bladder cancer were similar. Four cycles of neoadjuvant chemotherapy may improve the cancer-specific survival of patients with muscle-invasive bladder cancer It is reasonable and feasible for clinicians to use three or four cycles of neoadjuvant chemotherapy.

肌层浸润性膀胱癌（muscle-invasive bladder cancer, MIBC）的新辅助化疗（neoadjuvant chemotherapy, NAC）最优周期仍存在争议。本研究旨在通过对文献开展系统评价与荟萃分析，对比3周期与4周期新辅助化疗治疗肌层浸润性膀胱癌的疗效。研究系统检索并梳理了PubMed、Medline、Embase、Web of Science及Cochrane图书馆数据库中的相关研究。采用相对危险度（relative ratios, RRs）、风险比（Hazard ratios, HRs）及其95%置信区间（confidence intervals, CIs）作为结局指标的评估参数。纳入对比肌层浸润性膀胱癌患者接受3周期与4周期新辅助化疗后的病理缓解情况与预后的相关研究。本荟萃分析共纳入5项研究，涉及2190例患者，其中1016例接受3周期新辅助化疗，1174例接受4周期新辅助化疗。所有纳入研究均为回顾性队列研究。研究结果显示，4周期新辅助化疗的癌症特异性生存情况显著优于3周期（风险比HR=1.31，95%置信区间CI：1.03~1.67，P=0.029）。接受3周期与4周期化疗的患者总生存情况无显著差异（HR=1.18，95%CI：0.83~1.69，P=0.345）。同样，肌层浸润性膀胱癌患者接受3周期或4周期新辅助化疗后，病理客观缓解率（相对危险度RR=0.95，95%CI：0.81~1.11，P=0.515）与完全缓解率（RR=0.87，95%CI：0.69~1.11，P=0.256）均无显著差异。尽管4周期新辅助化疗的癌症特异性生存率优于3周期，但二者在肌层浸润性膀胱癌的病理缓解情况与预后整体相似。肌层浸润性膀胱癌患者接受3周期与4周期新辅助化疗的病理缓解率及总生存情况相近；4周期新辅助化疗或可改善肌层浸润性膀胱癌患者的癌症特异性生存。临床医师采用3周期或4周期新辅助化疗具备合理性与可行性。肌层浸润性膀胱癌患者接受3周期与4周期新辅助化疗的病理缓解率及总生存情况相近；4周期新辅助化疗或可改善肌层浸润性膀胱癌患者的癌症特异性生存，临床医师采用3周期或4周期新辅助化疗具备合理性与可行性。