Clinical significance of SUVmax on preoperative 18F-fluorodeoxyglucose positron emission tomography in patients who underwent R0-esophagectomy for esophageal cancer.

The standardized uptake value (SUV) is a marker of tumor glucose metabolism, detected using 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) and may reflect tumor aggressiveness. The purpose of this study was to evaluate the clinical significance of maximum SUV (SUVmax) of primary esophageal cancer (EC) lesions. A total of 86 patients with EC who underwent pre-treatment FDG-PET and R0-resection were included in our study. The mean patient age was 65 years, and 87% were men. Histologically, cancers included squamous cell carcinomas, adenocarcinomas, and other tumors in 72, 3, and 11 patients, respectively. Preoperative chemotherapy with or without radiotherapy was performed in 4 and 37 patients, respectively. Measured patient outcomes included the correlation between the SUVmax of the primary EC lesion and clinicopathological factors in patients who did not undergo preoperative treatment (n = 45), and the investigation of relapse-free survival (RFS) according to SUVmax and the relationship between SUVmax and recurrence sites in all patients (n=86). The mean SUVmax was 8.9 ± 4.6, and SUVmax values significantly correlated with tumor invasion depth and stage. The 5-year RFS for the enrolled patients was 57%, and the RFS of patients with SUVmax < 7.0 was better than that of patients with SUVmax ≥ 7.0, with a marginal difference (p = 0.0892). Lymph node recurrences were significantly more common in patients with SUVmax ≥ 7.0, compared to patients with SUVmax < 7.0. Therefore, the SUVmax value of the primary EC lesion before preoperative treatment may be predictive of RFS and lymph node recurrence.