Related Experiment Video
Updated: Oct 14, 2025

Competing-Risk Nomogram for Predicting Cancer-Specific Survival in Multiple Primary Colorectal Cancer Patients after Surgery
Published on: September 27, 2024
The Clinical Significance of CA19-9 and Tumor Size Ratios for Predicting Prognosis After Conversion Surgery in
Keishi Okubo1, Takaaki Arigami2,3, Daisuke Matsushita2
1Department of Digestive Surgery, Breast and Thyroid Surgery, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan; k5658877@kadai.jp.
Background/Aim:
The clinical benefit of conversion surgery (CS) after chemotherapy remains unclear for stage IV gastric cancer (GC) patients. This study aimed to investigate the prognostic factors used to determine whether CS is a promising therapeutic strategy.
Patients And Methods:
We retrospectively analyzed data from 156 patients diagnosed with unresectable stage IV GC who underwent chemotherapy as the initial treatment, including 40 patients who had R0 resection in CS.
Results:
The median survival time of the CS patients was significant longer than that of patients who underwent chemotherapy alone. A multivariate analysis identified only pN3 as an independent prognostic factor in CS patients. Among the differentiated tumor type patients, carbohydrate antigen 19-9 (CA19-9) levels were significantly higher in pN3 patients than in pN0-2 patients before chemotherapy. Among undifferentiated tumor type patients, pN3 patients had a significantly lower tumor size ratio (before chemotherapy/before surgery) than pN0-2 patients.
Conclusion:
Although it is clinically difficult to diagnose lymph node metastasis using preoperative examinations, CA19-9 levels and tumor size ratios may be preoperative indicators for predicting pN3, which is associated with a poor prognosis in CS.

