Retrospective Study
Copyright ©The Author(s) 2019. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastrointest Oncol. Jan 15, 2019; 11(1): 48-58
Published online Jan 15, 2019. doi: 10.4251/wjgo.v11.i1.48
Unnecessity of lymph node regression evaluation for predicting gastric adenocarcinoma outcome after neoadjuvant chemotherapy
Yue-Lu Zhu, Yong-Kun Sun, Xue-Min Xue, Jiang-Ying Yue, Lin Yang, Li-Yan Xue
Yue-Lu Zhu, Xue-Min Xue, Jiang-Ying Yue, Li-Yan Xue, Department of Pathology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China
Yong-Kun Sun, Lin Yang, Department of Medical Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China
Jiang-Ying Yue, Department of Pathology, Esophageal Carcinoma Hospital of Linzhou, Anyang 456592, Henan Province, China
Author contributions: Xue LY and Yang L designed this study; Sun YK and Zhu YL enrolled the patients and collected the clinical data; Zhu YL, Yue JY and Xue LY evaluated the pathological sections; Xue LY, Xue XM and Zhu YL conducted the statistical analyses; the manuscript was drafted by Zhu YL, Sun YK, and Yue JY and reviewed for content by Xue LY and Xue XM; All authors read and approved the final manuscript.
Supported by CAMS Innovation Fund for Medical Sciences, No. 2016-I2M-3-005; and the Beijing Hope Run Special Fund, No. LC2015A03 and No. LC2013B34.
Institutional review board statement: This study was conducted after obtaining approval from the Independent Ethics Committee at the National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, No. NCC2013RE-049.
Informed consent statement: Consent was not required from each patient because this was a retrospective study.
Conflict-of-interest statement: The authors declare that they have no competing interests.
Data sharing statement: The datasets used during and/or analyzed during the current study are available from the corresponding author upon reasonable request.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (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: Li-Yan Xue, MD, Professor, Department of Pathology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, No. 17 PanJiaYuanNanLi, Chaoyang District, Beijing 100021, China. xuely@cicams.ac.cn
Telephone: +86-10-87787514 Fax: +86-10-67702630
Received: September 28, 2018
Peer-review started: September 28, 2018
First decision: October 15, 2018
Revised: November 26, 2018
Accepted: December 24, 2018
Article in press: December 24, 2018
Published online: January 15, 2019
Abstract
BACKGROUND

Neoadjuvant chemotherapy has been applied worldwide to improve the survival of patients with gastric adenocarcinoma (GAC). The evaluation of histological regression in primary tumors is valuable for predicting prognosis. However, the prognostic effect of regression change in lymph nodes (LNs) remains unclear.

AIM

To confirm whether the evaluation of regression change in LNs could predict the prognosis of GAC patients who received neoadjuvant chemotherapy followed by surgery.

METHODS

In this study, we evaluated the histological regression of resected LNs from 192 GAC patients (including those with esophagogastric junction adenocarcinoma) treated with neoadjuvant chemotherapy. We classified regression change and residual tumor in LNs into four groups: (A) true negative LNs with no evidence of a preoperative therapy effect, (B) no residual metastasis but the presence of regression change in LNs, (C) residual metastasis with regression change in LNs, and (D) metastasis with minimal or no regression change in LNs. Correlations between regression change and residual tumor groups in LNs and regression change in the primary tumor, as well as correlations between regression change in LNs and clinicopathological characteristics, were analyzed. The prognostic effect of regression change and residual tumor groups in LNs was also analyzed.

RESULTS

We found that regression change and residual tumor groups in LNs were significantly correlated with regression change in the primary tumor, tumor differentiation, ypT stage, ypN stage, ypTNM stage, lymph-vascular invasion, perineural invasion and R0 resection status. Regression change and residual tumor groups in LNs were statistically significant using univariate Cox proportional hazards analysis, but were not independent predictors. For patients who had no residual tumor in LNs, the 5-year overall survival (OS) rates were 67.5% in Group A and 67.4% in Group B. For the patients who had residual tumors in LNs, the 5-year OS rates were 28.2% in Group C and 39.5% in Group D. The patients in Groups A+B had a significantly better outcome than the patients in Groups C+D (P < 0.01). No significant differences in survival were found between Groups A and B, or between Groups C and D.

CONCLUSION

The existence of residual tumor in LNs, rather than regression change in LNs, is useful for predicting the prognosis after neoadjuvant chemotherapy in GAC patients. In practice, it may not be necessary to report regression change in LNs.

Keywords: Gastric cancer, Neoadjuvant chemotherapy, Lymph nodes, Regression, Residual tumor, Regression change

Core tip: Neoadjuvant chemotherapy has been applied worldwide to improve the survival of patients with gastric adenocarcinoma (GAC). In this study, we evaluated the prognostic effect of regression change in lymph nodes (LNs) from 192 GAC patients treated with neoadjuvant chemotherapy. The existence of residual tumor in LNs, rather than regression change in LNs, is useful for predicting prognosis after neoadjuvant chemotherapy in GAC patients. In practice, it may not be necessary to report regression change in LNs.