We aimed to investigate the prognostic value of the relative maximum standardized uptake value (SUV) of metastatic lymph node (LN) compared with that of primary tumor (SUVLN/SUVTumor) based on a pretreatment [18F]-FDG PET/CT scan in patients with clinically node-positive esophageal squamous cell carcinoma (cN+ ESCC) treated with definitive chemoradiotherapy (dCRT). We retrospectively evaluated cN+ ESCC patients who underwent a PET/CT scan before dCRT. Time-dependent receiver operating characteristics analysis was performed to identify the optimal cutoff value for SUVLN/SUVTumor. Prognostic influences of SUVLN/SUVTumor on distant metastasis-free survival (DMFS) and overall survival (OS) were evaluated using the Kaplan–Meier method and log-rank test for univariate analysis and Cox’s proportional hazards regression model for multivariate analysis. We identified 112 patients with newly diagnosed cN+ ESCC. After a median follow-up of 32.0 months, 50 (44.6%) patients had distant failure and 84 (75.0%) patients died. Patients with high SUVLN/SUVTumor (≥ 0.39) experienced worse outcomes than low SUVLN/SUVTumor (< 0.39) (two-year DMFS: 26% vs. 70%, p < 0.001; two-year OS: 21% vs. 48%, p = 0.001). Multivariate analysis showed that SUVLN/SUVTumor was an independent prognostic factor for both DMFS (adjusted HR 2.24, 95% CI 1.34–3.75, p = 0.002) and OS (adjusted HR 1.61, 95% CI 1.03–2.53, p = 0.037). Pretreatment of SUVLN/SUVTumor is a simple and useful marker for prognosticating DMFS and OS in cN+ ESCC patients treated with dCRT, which may help in tailoring treatment and designing future clinical trials.

Background:In clinical trials, adjuvant therapy (AT) has been shown to improve the prognosis in patients with gastric adenocarcinoma who undergo curative gastrectomy and adequate lymph node dissection. However, the optimal timing for initiating AT is still unclear.Method:We collected data from 538 patients with stage II-III gastric cancer who underwent curative gastrectomy and AT in two tertiary hospitals from 2006 to 2013. Patients were divided into the early group (≤8 weeks, n=393) and the late group (>8 weeks, n=145), based on the interval between gastrectomy and initiation of AT. Propensity score matching was applied according to baseline characteristics.Results:After 1:1 propensity score matching, an even distribution of characteristics in both groups (143:143) was achieved. The 5-year overall survival (OS) rates were 56.6% and 40.2% in the matched early and late groups, respectively (p=0.062), while the corresponding 5-year recurrence-free survival (RFS) rates were 57.6% and 46.4%, respectively (p=0.028). The time to AT initiation was correlated with RFS and had a positive association with OS. The 5-year distant metastasis-free survival was also significantly better (HR 0.682, 95% CI 0.472-0.985, p=0.040), suggesting an early AT results in a better outcome in patients.Conclusion:We observed that initiation of AT within 8 weeks of curative gastrectomy produces better disease control and may contribute to better overall survival.

Absence of FDG-avid metastatic lymph node with at least partial response of the primary tumor on PET scan after CRT (i.e., yPET-F status) prognosticate for excellent OS and DMFS in cN+ ESCC patients treated with dCRT, and might be comparable to TMT.