Chair of Surgical Oncology, Collegium Medicum Nicolaus Copernicus University, Oncology Center-Prof Franciszek Łukaszczyk Memorial Hospital, Bydgoszcz, Poland.
Department of Radiotherapy I, M. Skłodowska-Curie National Research Institute of Oncology, Warsaw, Poland.
Radiother Oncol. 2021 Jul;160:229-235. doi: 10.1016/j.radonc.2021.05.014. Epub 2021 May 21.
Frequency and predictive factors for a clinical complete response (cCR) in unselected patients are unclear.
Two prospective observational studies were designed and pooled to explore predictive factors for cCR. Both studies evaluated the watch-and-wait strategy in consecutive patients; the first single-institutional study in elderly with a small tumour, the second multi-institutional study in all the patients receiving standard of care preoperative radiotherapy.
Four hundred and ninety patients were analysed. Short-course radiotherapy alone, or with consolidation chemotherapy or chemoradiation was given to 40.6%, 40.2% and 19.2% of the patients, respectively. The median interval from the radiation start to the first tumour response assessment was 10.2 weeks for short-course radiation and 13.2 weeks for chemoradiation. Seventy-three patients had cCR and 71 underwent w&w with the median follow-up of 24 months. The regrowth rate was 26.8%. cCR rate was 39.0% for low-risk cancer (cT1-2N0), 16.8% for intermediate-risk (cT3 with unthreatened mesorectal fascia [MRF-] or cT2N+) and 5.4% for high-risk (cT4 or MRF+). In the multivariable analysis, tumour volume (or tumour length and circumferential extent) and cN status were significant predictors for cCR. In circular cancers or with a length ≥7 cm (n = 184), cCR rate was only 2.7%, sustained cCR 1.6% and the sensitivity of cCR diagnosis 23.1%. None of 27 patients with a tumour larger than 120 cm achieved cCR.
Considering watch-and-wait strategy is questionable in patients with circular tumours or with tumour length ≥7 cm.
未选择患者中临床完全缓解（cCR）的频率和预测因素尚不清楚。
设计并汇总了两项前瞻性观察性研究，以探讨 cCR 的预测因素。这两项研究均评估了连续患者的观望等待策略；第一项单机构研究纳入了小肿瘤的老年患者，第二项多机构研究纳入了接受标准术前放疗的所有患者。
共分析了 490 名患者。分别有 40.6%、40.2%和 19.2%的患者接受了短程放疗联合巩固化疗或放化疗。短程放疗和放化疗的中位放疗开始至首次肿瘤反应评估的间隔时间分别为 10.2 周和 13.2 周。73 名患者获得 cCR，71 名患者行 w&w 治疗，中位随访时间为 24 个月。肿瘤复发率为 26.8%。低危癌症（cT1-2N0）的 cCR 率为 39.0%，中危（cT3 伴有未受威胁的中直肠筋膜[MRF-]或 cT2N+）为 16.8%，高危（cT4 或 MRF+）为 5.4%。多变量分析显示，肿瘤体积（或肿瘤长度和环周范围）和 cN 状态是 cCR 的显著预测因素。在圆形肿瘤或长度≥7cm 的患者（n=184）中，cCR 率仅为 2.7%，持续 cCR 率为 1.6%，cCR 诊断的敏感性为 23.1%。肿瘤大于 120cm 的 27 名患者均未达到 cCR。
对于圆形肿瘤或肿瘤长度≥7cm 的患者，考虑观望等待策略是值得怀疑的。
