title: Prognostic Value of Lymph Node Ratio in Locally Advanced Rectal Cancer Patients After Preoperative Chemoradiotherapy Followed by Total Mesorectal Excision.
abstract: Although the absolute number of positive lymph nodes (LNs) has been established as 1 of the most important prognostic factors in rectal cancers, many researchers have proposed that the lymph node ratio (LNR) may have better predicted outcomes. We conducted a retrospective study to compare the predictive ability of LNR and ypN category in rectal cancer. A total of 264 locally advanced rectal cancer (LARC) patients who underwent preoperative chemoradiotherapy (CRT) followed by total mesorectal excision (TME) between 2005 and 2012 were reviewed. All patients were categorized into 3 groups or patients with metastatic LNs were categorized into 2 groups according to the LNR. The prognostic effect on overall survival (OS) and disease-free survival (DFS) was evaluated. With a median follow-up of 45 months, the OS and DFS were 68.4% and 59.3% for the entire cohort, respectively. The respective 5-year OS and DFS rates for the 3 groups (LNR = 0, 0 < LNR ≤ 0.20, and 0.20 < LNR ≤ 1.0) were as follows: 83.2%, 72.6%, and 49.4% (P < 0.001) and 79.5%, 57.3%, and 33.5% (P < 0.001), respectively. Multivariate analysis revealed that LNR and differentiation, but not the number of positive LNs, had independent prognostic value for OS (hazard ratio [HR] = 2.328, 95% confidence interval [CI]: 1.850-4.526, P < 0.001) and DFS (HR = 3.004, 95% CI: 1.616-5.980, P < 0.001). As for patients with positive LNs, the respective 5-year OS and DFS rates for the 2 groups (0 < LNR ≤ 0.20, and 0.20 < LNR ≤ 1.0) were 72.6% and 49.4% (P < 0.001) and 57.3% and 33.5% (P < 0.001), respectively. Multivariate analysis revealed that only LNR was an independent factor for OS (HR = 3.214, 95% CI: 1.726-5.986, P < 0.001) and DFS (HR = 4.230, 95% CI: 1.825-6.458, P < 0.001). Subgroups analysis demonstrated that the ypN category had no impact on survival whereas increased LNR was a significantly prognostic indicator for worse survival in the LNs < 12 subgroup. LNR is an independent prognostic factor in LARC patients treated with preoperative CRT followed by TME. It may be a better independent staging method than the number of metastatic LNs when <12 LNs are harvested after preoperative CRT.
authors.affiliation: From the Department of Colorectal Surgery (Z-GZ, X-ZY, CX, X-BW, J-HC, Z-HZ, J-LL, H-YS, SCN), Department of Pathology (Z-QL, PL), and Central Laboratory (LJ), The First Affiliated Hospital of Wenzhou Medical University, Wenzhou; Department of Colorectal Surgery, The Third People's Hospital of Hangzhou City, Hangzhou (X-FZ); and Department of Colorectal Surgery, Changhai Hospital, The Second Military Medical University, Shanghai (HW, Q-ZL), China.
authors.forename: Zhi-Gui
authors.initials: ZG
authors.lastname: Zuo
authors.forename: Xiu-Feng
authors.initials: XF
authors.lastname: Zhang
authors.forename: Hao
authors.initials: H
authors.lastname: Wang
authors.forename: Qi-Zhi
authors.initials: QZ
authors.lastname: Liu
authors.forename: Xing-Zhao
authors.initials: XZ
authors.lastname: Ye
authors.forename: Chang
authors.initials: C
authors.lastname: Xu
authors.forename: Xiang-Bin
authors.initials: XB
authors.lastname: Wu
authors.forename: Jian-Hui
authors.initials: JH
authors.lastname: Cai
authors.forename: Zhen-Hua
authors.initials: ZH
authors.lastname: Zhou
authors.forename: Jin-Lei
authors.initials: JL
authors.lastname: Li
authors.forename: Hua-Yu
authors.initials: HY
authors.lastname: Song
authors.forename: Zu-Qiang
authors.initials: ZQ
authors.lastname: Luo
authors.forename: Peng
authors.initials: P
authors.lastname: Li
authors.forename: Shi-Chang
authors.initials: SC
authors.lastname: Ni
authors.forename: Lei
authors.initials: L
authors.lastname: Jiang
mesh_terms: D000230:Adenocarcinoma / Q000188:drug therapy / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D059186:Chemoradiotherapy, Adjuvant; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008197:Lymph Node Excision; D008198:Lymph Nodes / Q000473:pathology* / Q000601:surgery; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D011379:Prognosis; D012004:Rectal Neoplasms / Q000188:drug therapy / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D012007:Rectum / Q000473:pathology / Q000601:surgery*; D012189:Retrospective Studies; D016019:Survival Analysis
chemical_list: D000970:Antineoplastic Agents