Chen Zhifen, Sasaki Kazuhito, Murono Koji, Kawai Kazushige, Nozawa Hioaki, Kobayashi Hirotoshi, Ishihara Soichiro, Sugihara Kenichi
Department of Colorectal Surgery, The University of Tokyo Hospital, Bunkyo-ku, Tokyo, Japan.
Department of Surgery, Teikyo University, Mizonokuchi Hospital, Kawasaki-city, Kanagawa, Japan.
Ann Surg Oncol. 2022 Mar 3. doi: 10.1245/s10434-022-11372-z.
The American Joint Committee on Cancer tumor-node-metastasis staging system for rectal cancer defines lateral pelvic lymph nodes (LPLNs) only in the internal iliac region as regional. However, the Japanese Society for Cancer of the Colon and Rectum (JSCCR) staging system, also considers obturator lymph nodes (LNs) as regional. This retrospective cohort study evaluated the oncologic status of obturator LNs in low rectal cancer.
The study identified 3487 patients with pT3-T4 low rectal cancer who had undergone curative resections without preoperative radiotherapy or chemotherapy between 2003 and 2011 in the JSCCR database and divided them into six groups. Overall survival (OS) and recurrence-free survival (RFS) were analyzed by groups.
Histologic LPLN metastases were identified in 8% (279/3487) of all the patients and in 18.2% (279/1530) of the patients who underwent lateral pelvic node dissection. The 5-year OS and RFS rates of the obturator-LPLN group (P = 0.095) were worse than those of the internal-LPLN group (P = 0.075), but the difference was not significant. The OS of the obturator-LPLN group was similar to that of the resectable liver metastasis group (P = 0.731), and the RFS of the obturator-LPLN group was significantly better than that of the other-LPLN group (P = 0.016).
The prognosis for obturator LN metastases in low rectal cancer was not significantly worse than for internal iliac LN metastases, defined as regional by the current American Joint Committee on Cancer staging system, and the oncologic status of obturator LNs warrants more studies.
美国癌症联合委员会（AJCC）的直肠癌肿瘤-淋巴结-转移（TNM）分期系统仅将髂内区域的侧方盆腔淋巴结（LPLN）定义为区域淋巴结。然而，日本结直肠癌学会（JSCCR）的分期系统也将闭孔淋巴结（LN）视为区域淋巴结。这项回顾性队列研究评估了低位直肠癌中闭孔淋巴结的肿瘤学状况。
该研究在JSCCR数据库中识别出2003年至2011年间接受了根治性切除术且未进行术前放疗或化疗的3487例pT3-T4低位直肠癌患者，并将他们分为六组。对各组的总生存期（OS）和无复发生存期（RFS）进行分析。
在所有患者中，8%（279/3487）发现有组织学上的LPLN转移，在接受侧方盆腔淋巴结清扫的患者中，这一比例为18.2%（279/1530）。闭孔-LPLN组的5年OS率（P = 0.095）和RFS率（P = 0.075）比髂内-LPLN组差，但差异不显著。闭孔-LPLN组的OS与可切除肝转移组相似（P = 0.731），闭孔-LPLN组的RFS明显优于其他-LPLN组（P = 0.016）。
低位直肠癌中闭孔淋巴结转移的预后并不比美国癌症联合委员会当前分期系统定义为区域淋巴结的髂内淋巴结转移明显更差，闭孔淋巴结的肿瘤学状况值得更多研究。
