Propensity score analysis of 18-FDG PET/CT-enhanced staging in patients undergoing surgery for esophageal cancer

PET/CT is now integral to the staging pathway for potentially curable esophageal cancer (EC), primarily to identify distant metastases undetected by computed tomography. The aim of this study was to analyze the effect of PET/CT introduction on survival and assess patterns of recurrence after esophagectomy.

A longitudinal cohort of EC patients staged between 1998 and 2016 were considered for inclusion. After co-variate adjustment using propensity scoring, a cohort of 496 patients (273 pre-PET/CT and 223 post-PET/CT) who underwent esophagectomy [median age 63 years (31-80), 395 males, 425 adenocarcinomas, 71 squamous cell carcinomas, 325 neoadjuvant therapy] were included. The primary outcome measure was overall survival (OS) based on intention to treat.

Three-year OS pre-PET/CT was 42.5% compared with 57.8% post-PET/CT (Chi² 6.571, df 1, p = 0.004). On multivariable analysis, pT stage (HR 1.496 [95% CI 1.28-1.75], p < 0.0001), pN stage (HR 1.114 [95% CI 1.04-1.19], p = 0.001) and PET/CT staging (HR 0.688 [95% CI 0.53-0.89] p = 0.004) were independently associated with OS. Recurrent cancer was observed in 125 patients (51.4%) pre-PET/CT, compared with 74 patients post-PET/CT (37.8%, p = 0.004), and was less likely to be distant recurrence after PET/CT introduction (39.5 vs. 27.0%, p = 0.006).

Enhanced PET/CT staging is an important modality and independent factor associated with improved survival in patients undergoing esophagectomy for cancer.