Influence of the baseline 18F-fluoro-2-deoxy-D-glucose positron emission tomography results on survival and pathologic response in patients with gastroesophageal cancer undergoing chemoradiation

BACKGROUND: In patients with esophageal cancer who receive chemoradiation, tools to predict/prognosticate outcome before administering therapy are lacking. The authors evaluated initial standardized unit value (iSUV) of 18F-fluoro-2-deoxy-D-glucose positron emission tomography and its association with overall survival and the degree of pathologic response after surgery. METHODS: The authors analyzed 161 patients with esophageal adenocarcinoma who had chemoradiation followed by surgery. The log-rank test, univariate Cox proportional hazards model, Kaplan-Meier survival plot, and Fisher exact test were used to analyze dichotomized iSUV and its association with overall survival and pathologic response. RESULTS: The median age of 161 patients was 61 years (range, 26-80 years) and the majority of patients had lower esophageal or gastroesophageal junction involvement. All patients received fluoropyrimidine and, most commonly, a taxane or platinum compound with concomitant radiation. The median radiation dose was 45 grays (Gy) (range, 45 Gy-50.4 Gy). The median iSUV for all patients was 10.1 (range, 0-58). Using the Fisher exact test, iSUV was not found to be associated with the location of the primary cancer. iSUV higher than the median (10.1) was associated with a better pathologic response (P = .06). Patients with primary cancer with iSUV >10.1 had a lower risk for death (hazards ratio of 0.56) compared with those with iSUV ≤10.1. Higher iSUV was nonsignificantly associated with improved survival (P=.07). CONCLUSIONS: Data from the current study suggest that lower iSUV is associated with poor survival and lower probability of response to chemoradiation. iSUV needs to be further evaluated because it may be used to complement other imaging or biomarker assessments to individualize therapy.