Prediction model of objective response after neoadjuvant chemotherapy in patients with locally advanced gastric cancer

Abstract

Background: Neoadjuvant chemotherapy (NAC) plays an important role in the therapeutic strategy of locally advanced gastric cancer (LAGC). However, the response of LAGC after NAC varies among different patients. The objective response after NAC has proven to be an excellent indicator for benefiting from NAC, yet effective predictors of objective response are still lacking. The present study aimed to identify potential predictors of objective response in LAGC patients treated with NAC.

Methods: Clinicopathological data from 267 patients with LAGC who received NAC and met the inclusion criteria between July 2009 and December 2018 were retrospectively reviewed. Patients were randomly divided into the training and test sets at a 2:1 ratio. Univariate analysis was used to investigate whether any factors were correlated with objective response in the training set. Multivariate logistic regression analysis was applied to find independent predictors. A risk score model was then constructed based on the independent predictors, and its performance in predicting objective response was validated in the test set.

Results: Univariate analysis found that gender, age, short axis diameter of the largest regional lymph node (LN_max), serum total protein content, CEA detection value, tumor location, tumor differentiation, signet ring cell carcinoma component and Borrmann type were potential predictors for objective response. In multivariate logistic regression analysis, gender, LN_max and signet ring cell carcinoma component were independent predictors for objective response. Based on independent predictors, we developed a prediction model for objective response.

Conclusions: We found gender, LN_max and signet ring cell carcinoma component were independent predictors for objective response. The prediction model is a good tool to predict the objective response for LAGC patients treated with NAC, which can be applied to guide clinical practice.

Keywords: Local advanced gastric cancer; neoadjuvant chemotherapy; objective response; prediction model; recist; survival time.

Figure 1

The typical pathological pictures of well-differentiated (A, 25×; B, 400×) and signet ring cell carcinoma component (C, 25×; D, 400×) in gastric cancer.

Figure 2

ROC curve of the risk score model in the training (A) and test set (B).

Figure 3

Survival analysis of patients in different groups. A. Survival analysis for all patients between PR and SD+PD group. B. Survival analysis for patients in training group between PR and SD+PD. C. Survival analysis for patients in test group between PR and SD+PD. D. Survival analysis for all patients between High-Risk and Low-Risk group. E. Time to recurrence for all patients between High-Risk and Low-Risk group.