The role of FDG-PET in predicting prognosis for patients with advanced signet ring cell carcinoma

Abstract

Background and Objectives. The purpose of this study was to investigate the role of the standardized uptake values (SUV), a semi-quantitative assessment of tumor FDG uptake, as a prognosticator for advanced signet ring cell carcinoma (SRC).Methods. We reviewed the files of 41 patients who underwent curative gastrectomy for advanced SRC and who had an FDG-PET at initial presentation between September 2003 and December 2007. We used the maximal SUV for the analysis. Results. The median follow-up period was 30.9 months (range: 4.0-70.3). We found a correlation between the SUVmax and TNM stage. When the patients were divided into two groups (low vs. high SUVmax) based on a median SUVmax of 3.80, the high-SUVmax group showed more aggressive tumor behavior than did the low SUVmax group. In addition, the high SUVmax group showed more postoperative recurrence (P=0.028), shorter relapse-free survival (P=0.004) and lower 30-month cancer-specific survival rates (40.0% versus 69.3%, P=0.008). However, in multivariate analysis, SUVmax failed to be an independent predictor of overall survival. Conclusions. SUVmax at diagnosis is a valuable surrogate marker of tumor aggressiveness in advanced signet ring cell carcinoma, although it was not an independent predictor of overall survival after curative surgery.