Pericardial effusion after definitive concurrent chemotherapy and intensity modulated radiotherapy for esophageal cancer

Background: The literature regarding pericardial effusion after definitive concurrent chemotherapy and intensity modulated radiotherapy (IMRT) for esophageal cancer was lacking. This study aimed to investigate the risk factors of pericardial effusion in esophageal cancer patients undergoing definitive concurrent chemotherapy and IMRT. Methods: A total of 126 consecutive esophageal cancer patients treated with definitive concurrent chemotherapy and IMRT between 2008 and 2018 were reviewed. The pericardial effusion was determined on computed tomography scan of the chest and graded by the Common Terminology Criteria for Adverse Events, version 4.0. The cumulative incidence of pericardial effusion was estimated by the Kaplan-Meier method and compared between groups by the log-rank test. The risk factors of pericardial effusion were determined with multivariate Cox proportional hazards regression analysis. Results: The median follow-up time was 14.0 months. Thirty-seven (29.4%) patients had pericardial effusion after a median interval of 6.6 months since the end of IMRT. The cumulative incidence of pericardial effusion of any grade was higher in patients with mean heart dose > 23.45 Gy (p = 0.00018), heart V30 > 33.55% (p = 0.00015), mean pericardium dose > 20.33 Gy (p = 0.00027), and pericardium V20 > 42.55% (p = 0.00018). Furthermore, eight (6.3%) patients had symptoms related to pericardial effusion and were considered as cases with pericardial effusion ≥ grade 3. The cumulative incidence of pericardial effusion ≥ grade 3 was higher in patients with pericardium V30 > 65.80% (p = 0.00028), V40 > 55.35% (p < 0.0001), and V60 > 24.70% (p = 0.0021). Multivariate analyses showed the above dose-volume parameters predicted the risk of pericardial effusion in esophageal cancer. Conclusions: Dose-volume parameters predicting the risk of pericardial effusion were identified in esophageal cancer treated with definitive concurrent chemotherapy and IMRT. They could be applied as constraints of IMRT for esophageal cancer.