Retrospective Cohort Study
Copyright ©The Author(s) 2020. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Cases. Jan 6, 2021; 9(1): 24-35
Published online Jan 6, 2021. doi: 10.12998/wjcc.v9.i1.24
Log odds of positive lymph nodes is a better prognostic factor for oesophageal signet ring cell carcinoma than N stage
Feng Wang, Shu-Geng Gao, Qi Xue, Feng-Wei Tan, Yu-Shun Gao, You-Sheng Mao, Da-Li Wang, Jun Zhao, Yin Li, Xiang-Yang Yu, Hong Cheng, Chen-Guang Zhao, Ju-Wei Mu
Feng Wang, Shu-Geng Gao, Qi Xue, Feng-Wei Tan, Yu-Shun Gao, You-Sheng Mao, Da-Li Wang, Jun Zhao, Yin Li, Xiang-Yang Yu, Hong Cheng, Chen-Guang Zhao, Ju-Wei Mu, Department of Thoracic Surgery, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China
Author contributions: Wang F drafted the manuscript, got data from the SEER database, and assisted with data analysis; Gao SG participated in design and oversight of the study; Xue Q and Tan FW participated in design of the study and were involved in data collection; Gao YS, Mao YS, Wang DL, Zhao J, and Li Y participated in study design; Yu XT, Cheng H, and Zhao CG were involved in data collection and statistical analysis; all authors read and approved the final manuscript.
Supported by the Capital Health Development Research Project, No. 2014-1-4021.
Institutional review board statement: The study was reviewed and approved for publication by National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College Institutional Review Board.
Informed consent statement: As the study cohort is based on a publicly available database without identifying patient information, informed consent was not needed. Informed consent was provided by all cases in the validation cohort.
Conflict-of-interest statement: All the authors have no conflict of interest related to the article.
Data sharing statement: No additional data are available.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Ju-Wei Mu, MD, Doctor, Professor, Surgeon, Surgical Oncologist, Department of Thoracic Surgery, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, National Cancer Center, No. 17 Panjiayuan Nanli, Chaoyang District, Beijing 100021, China. mujuwei@cicams.ac.cn
Received: June 27, 2020
Peer-review started: June 27, 2020
First decision: September 30, 2020
Revised: October 9, 2020
Accepted: November 2, 2020
Article in press: November 2, 2020
Published online: January 6, 2021
Abstract
BACKGROUND

Signet ring cell carcinoma is a rare type of oesophageal cancer, and we hypothesized that log odds of positive lymph nodes (LODDS) is a better prognostic factor for oesophageal signet ring cell carcinoma.

AIM

To explore a novel prognostic factor for oesophageal signet ring cell carcinoma by comparing two lymph node-related prognostic factors, log odds of positive LODDS and N stage.

METHODS

A total of 259 cases of oesophageal signet ring cell carcinoma after oesopha-gectomy were obtained from the Surveillance, Epidemiology, and End Results database between 2006 and 2016. The prognostic value of LODDS and N stage for oesophageal signet ring cell carcinoma was evaluated by univariate and multivariate analyses. The Akaike information criterion and Harrell’s C-index were used to assess the value of two prediction models based on lymph nodes. External validation was performed to further confirm the conclusion.

RESULTS

The 5-year cancer-specific survival (CSS) and 5-year overall survival (OS) rates of all the cases were 41.3% and 27.0%, respectively. The Kaplan-Meier method showed that LODDS had a higher score of log rank chi-squared (OS: 46.162, CSS: 41.178) than N stage (OS: 36.215, CSS: 31.583). Univariate analyses showed that insurance, race, T stage, M stage, TNM stage, radiation therapy, N stage, and LODDS were potential prognostic factors for OS (P < 0.1). The multivariate Cox regression model showed that LODDS was an significant independent prognostic factor for oesophageal signet ring carcinoma patients after surgical resection (P < 0.05), while N stage was not considered to be a significant prognostic factor (P = 0.122). Model 2 (LODDS) had a higher degree of discrimination and fit than Model 1 (N stage) (LODDS vs N stage, Harell’s C-index 0.673 vs 0.656, P < 0.001; Akaike information criterion 1688.824 vs 1697.519, P < 0.001). The results of external validation were consistent with those in the study cohort.

CONCLUSION

LODDS is a superior prognostic factor to N stage for patients with oesophageal signet ring cell carcinoma after oesophagectomy.

Keywords: Oesophageal neoplasms, Signet ring cell, Lymph nodes, Prognosis, Log odds of positive lymph nodes, TNM stage

Core Tip: This study showed that log odds of positive lymph nodes (LODDS) was an independent prognostic factor for oesophageal signet ring carcinoma patients after surgical resection, while N stage was not considered to be a significant prognostic factor. Prognosis model based on LODDS had a higher degree of discrimination and fit than the model based on N stage. In conclusion, LODDS is a superior prognostic factor to N stage for patients with signet ring cell carcinoma after oesophagectomy.