Department of Gastrointestinal Surgery, West China Hospital, Sichuan University, Chengdu, China.
Colorectal Cancer Clinical Research Center, The Third Affiliated Hospital of Kunming Medical University, Kunming, China.
Ann Surg. 2020 Dec;272(6):1060-1069. doi: 10.1097/SLA.0000000000003649.
The aim of this study was to compare stage II/III rectal cancers with or without high-risk factors, and evaluate the effect of neoadjuvant radiotherapy (NRT) in these 2 cohorts.
NRT is often used in stage II/III rectal cancers to improve local control, while not affecting overall survival. However, good-quality surgery without NRT may also achieve good local control in selected patients.
According to risk-stratification criteria and clinical staging, consecutive eligible participants of stage II/III rectal cancer were preoperatively classified into patients with (high-risk) or without (low-risk) high-risk factors. Both groups were respectively randomized to receive either short-course radiotherapy (SCRT) + total mesorectal excision (TME) or TME alone, forming the following 4 groups: high-risk patients with (HiR) or without (HiS) radiation, and low-risk patients with (LoR) or without (LoS) radiation. The primary endpoint was local recurrence. The secondary endpoints included overall survival, disease-free survival, distant recurrence, quality of surgery, and safety (NCT01437514).
In total, 401 patients were analyzed. With a median 54 months' follow-up, low-risk patients obtained better 3-year cumulative incidence of local recurrence (2.2% vs 11.0%, P = 0.006), overall survival rate (86.9%vs 76.5%, P = 0.002), disease-free survival rate (87.0% vs 67.9%, P < 0.001), and cumulative incidence of distant recurrence (12.5% vs 29.4%, P < 0.001) than high-risk patients. With regard to 3-year cumulative incidence of local recurrence, no differences were observed between the LoR and LoS groups (1.2% vs 3.0%, P = 0.983) or the HiR and HiS groups (12.9% vs 8.9%, P = 0.483).
Stratification of stage II/III rectal cancers according to risk factors to more precise subclassifications may result in noteworthy differences in survivals and local pelvic control. An extremely low cumulative incidence of local recurrence and survivals in low-risk patients can be achieved with upfront good quality of surgery alone. This trial, owing to the insufficient power, could not prove the noninferiority of surgery alone, but suggest a discriminative use of NRT according to clinical risk stratification in stage II/III rectal cancer.
本研究旨在比较有或无高危因素的 II/III 期直肠癌，并评估这两组患者新辅助放疗（NRT）的效果。
NRT 常被用于 II/III 期直肠癌，以提高局部控制率，而不影响总生存率。然而，对于选择的患者，不进行 NRT 的高质量手术也可能获得良好的局部控制。
根据风险分层标准和临床分期，将连续符合条件的 II/III 期直肠癌患者术前分为有（高危）或无（低危）高危因素的患者。两组患者分别随机接受短程放疗（SCRT）+全直肠系膜切除术（TME）或 TME 单独治疗，形成以下 4 组：有（HiR）或无（HiS）放疗的高危患者，以及有（LoR）或无（LoS）放疗的低危患者。主要终点是局部复发。次要终点包括总生存率、无病生存率、远处复发、手术质量和安全性（NCT01437514）。
共分析了 401 例患者。中位随访 54 个月后，低危患者的 3 年局部复发累积发生率（2.2% vs 11.0%，P=0.006）、总生存率（86.9% vs 76.5%，P=0.002）、无病生存率（87.0% vs 67.9%，P<0.001）和远处复发累积发生率（12.5% vs 29.4%，P<0.001）均优于高危患者。在 3 年局部复发累积发生率方面，LoS 组与 LoR 组（1.2% vs 3.0%，P=0.983）或 HiS 组与 HiR 组（12.9% vs 8.9%，P=0.483）之间无差异。
根据危险因素对 II/III 期直肠癌进行分层，以进行更精确的亚分类，可能导致生存率和局部盆腔控制方面的显著差异。低危患者单独进行高质量手术即可获得极低的局部复发累积发生率和生存率。由于本试验的效力不足，无法证明单独手术的非劣效性，但提示在 II/III 期直肠癌中根据临床风险分层有区别地使用 NRT。
