Retrospective Study
Copyright ©The Author(s) 2020. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastrointest Oncol. Jan 15, 2020; 12(1): 101-112
Published online Jan 15, 2020. doi: 10.4251/wjgo.v12.i1.101
Adenosquamous carcinoma may have an inferior prognosis to signet ring cell carcinoma in patients with stages I and II gastric cancer
Yu-Xin Chu, Hong-Yun Gong, Qin-Yong Hu, Qi-Bin Song
Yu-Xin Chu, Hong-Yun Gong, Qin-Yong Hu, Qi-Bin Song, Department of Oncology (Division I), Cancer Center, Renmin Hospital of Wuhan University, Wuhan 430060, Hubei Province, China
Author contributions: Chu YX drafted the manuscript; Gong HY performed data extraction; Hu QY performed statistical analysis; and Song QB supervised the study.
Supported by the National Natural Science Foundation of China, No. 81670123 and No. 81670144.
Institutional review board statement: This study was approved by the Institutional Review Board of Wuhan University Renmin Hospital.
Informed consent statement: The patients were not required to give informed consent to the study because the analysis used anonymous clinical data that were obtained after each patient agreed to treatment by written consent.
Conflict-of-interest statement: We have no financial relationships to disclose.
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:
Corresponding author: Qinyong Hu, MD, Academic Research, Department of Oncology I, Cancer Center, Renmin Hospital of Wuhan University, Jiefang Road No. 238, Wuhan 430060, Hubei Province, China.
Received: August 30, 2019
Peer-review started: August 30, 2019
First decision: October 14, 2019
Revised: October 25, 2019
Accepted: October 31, 2019
Article in press: October 31, 2019
Published online: January 15, 2020
Processing time: 123 Days and 2.3 Hours
Research background

Adenosquamous carcinoma (ASC) is a rare entity in gastric cancer, which exhibits early tumor progression and a poorer prognosis than other typical gastric adenocarcinoma. Gastric signet ring cell carcinoma (SRC) is a unique subtype with distinct tumor biology and clinical features. We hypothesized that further knowledge about these distinct cancers would improve the clinical management of such patients.

Research motivation

Given the relative rarity of these two subtypes in gastric cancer, the study on gastric ASC with large series is still lacking. The clinicopathological characteristics and prognosis of ASC vs SRC has not been well established to date. The current study adopted a large cohort of such patients from the Surveillance, Epidemiology, and End Results (SEER) database. Study on the clinicopathological features, treatment, and prognosis of such patients may bring deeper knowledge on these tumors and provide additional assistance for their treatment.

Research objectives

The goal of our study was to evaluate the clinicopathological characteristics and prognosis of ASC vs SRC based on a large cohort from the SEER database. Achieving this objective may provide additional assistance for their management.

Research methods

We conducted a retrospective study using a large cohort from the SEER database. The clinicopathological features of patients with ASC vs SRC were comprehensively compared by chi-square tests. We used both propensity-score matching (PSM) method and multivariate Cox regression analysis to adjust the potential bias caused by the imbalanced distribution of confounding factors. Clinical outcomes including cancer-specific survival (CSS) and overall survival (OS) were also compared by the Kaplan-Meier method. The prognostic factors were identified.

Research results

A total of 6063 eligible patients were collected. After PSM, 370 patients with SRC and 95 patients with ASC were analyzed. In the post-matching cohort, gastric ASC showed an inferior prognosis to SRC in both CSS and OS. ASC and higher TNM stage were independently associated with a poor survival (HR > 1, P < 0.05), while radiotherapy (HR = 0.587; 95%CI: 0.444-0.776, P < 0.001) and surgery were independent protective factors for favorable prognosis (HR < 1, P < 0.05). Subgroup survival analysis revealed that the inferior prognosis was most significant in stages I and II patients.

Research conclusions

ASC may have an inferior prognosis to SRC in patients with stages I and II gastric cancer, so greater attention should be paid to these patients. Our study supports radiotherapy and surgery for the future management of this clinically rare entity. Improved clinical and biological understanding of ASC vs SRC may lead to more individualized therapy for such patients.

Research perspectives

Our study shows that gastric ASC has an inferior prognosis to SRC in stages I and II patients. Precautions should be taken to such patients. Radiotherapy and surgery have the potential to improve their clinical outcomes. Future long-term prospective studies are warranted to validate our findings.