Distribution and timing of distant metastasis after local therapy in a large cohort of patients with esophageal and esophagogastric junction cancer

Background: Patients with localized esophageal and esophagogastric junction cancer (EAC) receive chemoradiation and then surgery (trimodality, TMT) or definitive chemoradiation (bimodality, BMT). Distant metastases (DMs) are common but the details of their distribution and timing in a large cohort have not been described. Methods: 629 patients with localized EAC who had TMT or BMT were analyzed. Standard statistical methods were used to define the end points. Results: The median follow-up time was 37.2 months (interquartile range 17.8-65.0). Of 356 TMT patients, 33% (119) developed DM as their first relapse and of 273 BMT patients, 40% (109) developed DM; 91% (TMT) and 96% (BMT) of the DMs were diagnosed within 2 years of local therapy. The most common sites of DM were: lung, distant nodes, liver, peritoneal cavity, bone, brain and pleura in order of frequency. The median overall survival of TMT patients with DM was 10.2 months (95% CI 7.8-12.7) and that for BMT patients with DM was 7.8 months (95% CI 5.7-9.9). Conclusions: Following TMT or BMT, ≥33% of patients developed DMs and most of these occurred within 2 years (>90%) of local therapy. A clinical model is desirable that associates clinical parameters with a high risk for DM in TMT-eligible patients prior to surgery.