The relationship between local, regional, or distant disease control (LC, RC, DC) and maximal posttreatment standardized uptake value (SUVmax) in patients with esophageal cancer has not been elucidated. This study was initiated to explore whether a decrease in SUV on positron emission tomography-computed tomography (PET-CT) scan is associated with LC, RC, or DC in patients with esophageal carcinoma treated with definitive chemoradiotherapy.
Medical records of 40 patients with inoperable esophageal cancer treated with definitive intent and who underwent pre- and posttreatment PET-CT scans were reviewed. The histology, nodal status, tumor location, and radiotherapy (RT) dose were investigated as variables to determine a relationship between SUVmax and LC, RC, and DC as well as disease-free survival (DFS).
Decreased posttreatment SUVmax on PET scan (P = .02) and increased RT dose (P = .009) were the only significant predictors of improved LC on univariate analysis. Mean RT doses in patients with no evidence of disease or with local, regional, or distant recurrences were 5,244, 4,580, 5,094, and 4,968, respectively. Decreased posttreatment SUV (P = .03) and increased RT dose (P = .008) were also associated with an improvement in DFS. Furthermore, decreased posttreatment SUVmax correlated with an improvement in LC (hazard ratio [HR] = 1.3, 95% confidence interval [CI] = 1.03–1.6, P = .03) as well as DFS (HR = 1.3, 95% CI = 1.03–1.6, P = .03). These findings were maintained on multivariate analysis.
Posttreatment decrease in SUV is associated with LC and DFS in esophageal cancer patients receiving definitive chemoradiotherapy. RT dose was also associated with both LC and DFS. The prognostic significance of these findings warrants prospective confirmation.