The Japan Society for Endoscopic Surgery, Tokyo, Japan.
Department of Surgery, Surgical Oncology and Science, Sapporo Medical University, S1 W16, Chuo-ku, Sapporo, 060-8543, Japan.
Surg Today. 2022 Sep;52(9):1275-1283. doi: 10.1007/s00595-022-02481-z. Epub 2022 Apr 4.
A circumferential resection margin (CRM) > 1 mm is a surrogate marker of oncologic outcomes in rectal cancer patients. In Japan, because the mesentery is removed from the rectum, the CRM cannot be measured. This multicenter prospective study evaluates the feasibility of a resected specimen processing method that allows CRM measurement.
Fifty patients with rectal cancer were enrolled. Resected specimens were processed as previously reported. The primary outcomes were CRM measurement and the rate of CRM positivity. The secondary outcomes were the quality of total mesorectal excision, the possibility to visualize and sample the tumor, the number of harvested lymph nodes, and comparison between the pathological CRM and preoperative mesorectal fascia (MRF) involvement. This study was registered in the University Hospital Medical Information Network (UMIN) Clinical Trials Registry under identification number UMIN000031735.
The CRM was measurable in all patients and found to be positive in three (6%). We confirmed tumor localization, sampled the tumor, and measured the distal margin in all patients. A median of 20 lymph nodes were harvested. The concordance rate between preoperative MRF involvement and pathological CRM status was 90%.
A semi-opened rectal specimen with transverse slicing is a feasible method for measuring the CRM.
环周切缘（CRM）＞1 毫米是直肠癌患者肿瘤学结果的替代标志物。在日本，由于直肠系膜从直肠中切除，因此无法测量 CRM。这项多中心前瞻性研究评估了一种允许测量 CRM 的切除标本处理方法的可行性。
纳入 50 例直肠癌患者。按照先前的报道对切除标本进行处理。主要结局是 CRM 测量和 CRM 阳性率。次要结局是全直肠系膜切除术的质量、肿瘤可视化和取样的可能性、采集的淋巴结数量，以及病理 CRM 与术前直肠筋膜（MRF）受累之间的比较。本研究在大学医院医疗信息网络（UMIN）临床试验注册处注册，注册号为 UMIN000031735。
所有患者的 CRM 均可测量，其中 3 例（6%）为阳性。我们在所有患者中均确认了肿瘤定位、取样肿瘤，并测量了远端切缘。中位数采集了 20 个淋巴结。术前 MRF 受累与病理 CRM 状态之间的一致性率为 90%。
对横向切片的半开放式直肠标本进行 CRM 测量是一种可行的方法。
