Battersby Nicholas J, How Peter, Moran Brendan, Stelzner Sigmar, West Nicholas P, Branagan Graham, Strassburg Joachim, Quirke Philip, Tekkis Paris, Pedersen Bodil Ginnerup, Gudgeon Mark, Heald Bill, Brown Gina
*Pelican Cancer Foundation, Basingstoke, United Kingdom †North Hampshire Hospital, Basingstoke, United Kingdom ‡Dresden-Friedrichstadt General Hospital, Dresden, Germany §Pathology & Tumor Biology, Leeds Institute of Cancer and Pathology, University of Leeds, Leeds, United Kingdom ¶Salisbury District Hospital, Salisbury, United Kingdom ||Vivantes im Friedrichshain, Berlin, Germany **The Royal Marsden NHS Foundation Trust, London, United Kingdom ††Aarhus University Hospital, Aarhus, Denmark ‡‡Frimley Park Hospital, Frimley, United Kingdom §§The Academic Department for Radiology, The Royal Marsden Hospital, Sutton, United Kingdom.
Ann Surg. 2016 Apr;263(4):751-60. doi: 10.1097/SLA.0000000000001193.
This study aimed to validate a magnetic resonance imaging (MRI) staging classification that preoperatively assessed the relationship between tumor and the low rectal cancer surgical resection plane (mrLRP).
Low rectal cancer oncological outcomes remain a global challenge, evidenced by high pathological circumferential resection margin (pCRM) rates and unacceptable variations in permanent colostomies.
Between 2008 and 2012, a prospective, observational, multicenter study (MERCURY II) recruited 279 patients with adenocarcinoma 6 cm or less from the anal verge. MRI assessed the following: mrLRP "safe or unsafe," venous invasion (mrEMVI), depth of spread, node status, tumor height, and tumor quadrant. MRI-based treatment recommendations were compared against final management and pCRM outcomes.
Overall pCRM involvement was 9.0% [95% confidence interval (CI), 5.9-12.3], significantly lower than previously reported rates of 30%. Patients with no adverse MRI features and a "safe" mrLRP underwent sphincter-preserving surgery without preoperative radiotherapy, resulting in a 1.6% pCRM rate. The pCRM rate increased 5-fold for an "unsafe" compared with "safe" preoperative mrLRP [odds ratio (OR) = 5.5; 95% CI, 2.3-13.3)]. Posttreatment MRI reassessment indicated a "safe" ymrLRP in 33 of 113 (29.2%), none of whom had ypCRM involvement. In contrast, persistent "unsafe" ymrLRP posttherapy resulted in 17.5% ypCRM involvement. Further independent MRI assessed risk factors were EMVI (OR = 3.8; 95% CI, 1.5-9.6), tumors less than 4.0 cm from the anal verge (OR = 3.4; 95% CI, 1.3-8.8), and anterior tumors (OR = 2.8; 95% CI, 1.1-6.8).
The study validated MRI low rectal plane assessment, reducing pCRM involvement and avoiding overtreatment through selective preoperative therapy and rationalized use of permanent colostomy. It also highlights the importance of posttreatment restaging.
本研究旨在验证一种磁共振成像（MRI）分期分类方法，该方法可在术前评估肿瘤与低位直肠癌手术切除平面（mrLRP）之间的关系。
低位直肠癌的肿瘤学治疗效果仍然是一项全球性挑战，高病理环周切缘（pCRM）率以及永久性结肠造口术存在不可接受的差异就证明了这一点。
在2008年至2012年期间，一项前瞻性、观察性、多中心研究（MERCURY II）招募了279例距肛缘6厘米及以下的腺癌患者。MRI评估了以下内容：mrLRP“安全或不安全”、静脉侵犯（mrEMVI）、浸润深度、淋巴结状态、肿瘤高度和肿瘤象限。将基于MRI的治疗建议与最终治疗及pCRM结果进行比较。
总体pCRM累及率为9.0%[95%置信区间（CI），5.9 - 12.3]，显著低于先前报道的30%的比率。没有不良MRI特征且mrLRP“安全”的患者在未进行术前放疗的情况下接受了保肛手术，pCRM率为1.6%。与术前mrLRP“安全”相比，“不安全”的患者pCRM率增加了5倍[比值比（OR）= 5.5；95% CI，2.3 - 13.3]。治疗后MRI重新评估显示，113例中有33例（29.2%）的ymrLRP“安全”，其中无一例有ypCRM累及。相比之下，治疗后持续“不安全”的ymrLRP导致ypCRM累及率为17.5%。进一步经独立MRI评估的危险因素为EMVI（OR = 3.8；95% CI，1.5 - 9.6）、距肛缘小于4.0厘米的肿瘤（OR = 3.4；95% CI，1.3 - 8.8）以及前部肿瘤（OR = 2.8；95% CI，1.1 - 6.8）。
该研究验证了MRI对低位直肠平面的评估，通过选择性术前治疗和合理使用永久性结肠造口术降低了pCRM累及率并避免了过度治疗。它还强调了治疗后重新分期的重要性。
