Background: Induction therapy is not always beneficial for all patients. Therefore, it is important to identify the patients with a high rate of recurrence. The occurrence of lymph node metastases (LNMs) strongly influences the postoperative survival in patients with esophageal cancer. We investigated the usefulness of an LN evaluation by initial (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET) in prediction of postoperative recurrence for patients with resectable esophageal squamous cell carcinoma (ESCC).
Methods: A total of 76 ESCC patients who did not undergo induction therapy, but who did receive a curative resection were divided into PET-node (PET-N) positive (n = 26) and negative (n = 50) groups according to the presence or absence of FDG uptake in LNs. The PET-N status was compared with the size and the number of LNMs, as well as with the survival and failure patterns.
Results: PET positive LNs involved a significantly larger size of metastatic nests than PET negative LNs (P = 0.002). The PET-N negative group showed a higher proportion of patients with 2 or fewer LNMs (92.0%), a higher 5-year relapse-free survival (75.1%) and a higher overall survival (70.0%), and a lower postoperative recurrence (24.0%) than the 15.4, 29.6, 30.3, and 69.2% values in the PET-N positive group, respectively, (P < 0.005). Multivariate analyses identified the PET-N status to be the most significant preoperative risk factor for postoperative recurrence (P = 0.031).
Conclusion: The preoperative PET-N status in patients with resectable ESCC was significantly associated with the size and the number of LNMs and was therefore found to reliably identify the high-risk population for postoperative recurrence.