Department of Gastrointestinal Medical Oncology, Harbin Medical University Cancer Hospital, Harbin, People's Republic of China.
Department of Thoracic Radiotherapy, Harbin Medical University Cancer Hospital, Harbin, People's Republic of China.
Oncologist. 2023 Dec 11;28(12):e1198-e1208. doi: 10.1093/oncolo/oyad151.
Circulating tumor DNA (ctDNA) is increasingly used as a biomarker for metastatic rectal cancer and has recently shown promising results in the early detection of recurrence risk.
We conducted a systematic review and meta-analysis to explore the prognostic value of ctDNA detection in LARC patients undergoing neoadjuvant chemoradiotherapy (nCRT). We systematically searched electronic databases for observational or interventional studies that included LARC patients undergoing nCRT. Study selection according to the PRISMA guidelines and quality assessment of the REMARK tool for biomarker studies. The primary endpoint was the impact of ctDNA detection at different time points (baseline, post-nCRT, post-surgery) on relapse-free survival (RFS) and overall survival (OS). The secondary endpoint was to study the association between ctDNA detection and pathological complete response(pCR) at different time points.
After further review and analysis of the 625 articles initially retrieved, we finally included 10 eligible studies. We found no significant correlation between ctDNA detection at baseline and long-term survival outcomes or the probability of achieving a pCR. However, the presence of ctDNA at post-nCRT was associated with worse RFS (HR = 9.16, 95% CI, 5.48-15.32), worse OS (HR = 8.49, 95% CI, 2.20-32.72), and worse pCR results (OR = 0.40, 95%CI, 0.18-0.89). The correlation between the presence of ctDNA at post-surgery and worse RFS was more obvious (HR = 14.94; 95% CI, 7.48-9.83).
Our results suggest that ctDNA detection is a promising biomarker for the evaluation of response and prognosis in LARC patients undergoing nCRT, which merits further evaluation in the following prospective trials.
循环肿瘤 DNA（ctDNA）越来越多地被用作转移性直肠癌的生物标志物，并且最近在复发风险的早期检测中显示出有希望的结果。
我们进行了系统评价和荟萃分析，以探讨接受新辅助放化疗（nCRT）的 LARC 患者中 ctDNA 检测的预后价值。我们系统地搜索了电子数据库，以查找包括接受 nCRT 的 LARC 患者在内的观察性或干预性研究。根据 PRISMA 指南进行研究选择，并使用 REMARK 工具对生物标志物研究进行质量评估。主要终点是不同时间点（基线，nCRT 后，手术后）ctDNA 检测对无复发生存（RFS）和总生存（OS）的影响。次要终点是研究不同时间点 ctDNA 检测与病理完全缓解（pCR）之间的关联。
在进一步审查和分析最初检索到的 625 篇文章后，我们最终纳入了 10 项合格的研究。我们发现基线时 ctDNA 检测与长期生存结果或实现 pCR 的可能性之间没有显着相关性。但是，nCRT 后存在 ctDNA 与较差的 RFS（HR = 9.16，95％CI，5.48-15.32），较差的 OS（HR = 8.49，95％CI，2.20-32.72）和较差的 pCR 结果（OR = 0.40，95％CI，0.18-0.89）相关。手术后存在 ctDNA 与较差 RFS 的相关性更为明显（HR = 14.94；95％CI，7.48-9.83）。
我们的结果表明，ctDNA 检测是评估接受 nCRT 的 LARC 患者反应和预后的有前途的生物标志物，值得在以下前瞻性试验中进一步评估。
