Incidence and Risk Factors for Diaphragmatic Herniation Following Esophagectomy for Cancer

Objective: To evaluate the incidence and risk factors of diaphragmatic herniation following esophagectomy for cancer (DHEC), and assess the results of surgical repair. Summary Background data: The current incidence of DHEC is discussed with conflicting data regarding its treatment and natural course. Methods: Monocentric retrospective cohort study (2009-2018). From 902 patients, 719 patients with a complete follow-up of CT scans after transthoracic esophagectomy for cancer were reexamined to identify the occurrence of a DHEC. The incidence of DHEC was estimated using Kalbfleisch and Prentice method and risk factors of DHEC were studied using the Fine and Gray competitive risk regression model by treating death as a competing event. Survival was analyzed. Results: Five-year DHEC incidence was 10.3% [95% CI, 7.8%-13.2%] (n = 59), asymptomatic in 54.2% of cases. In the multivariable analysis, the risk factors for DHEC were: presence of hiatal hernia on preoperative CT scan (HR = 1.72 [1.01-2.94], P = 0.046), previous hiatus surgery (HR = 3.68 [1.61-8.45], P = 0.002), gastroesophageal junction tumor location (HR = 3.51 [1.91-6.45], P < 0.001), neoadjuvant chemoradiotherapy (HR = 4.27 [1.70-10.76], P < 0.001), and minimally invasive abdominal phase (HR = 2.98 [1.60-5.55], P < 0.001). A cure for DHEC was achieved in 55.9%. The postoperative mortality rate was nil, the overall morbidity rate was 12.1%, and the DHEC recurrence rate was 30.3%. Occurrence of DHEC was significantly associated with a lower hazard rate of death in a time-varying Cox's regression analysis (HR = 0.43[0.23-0.81], P = 0.010). Conclusions: The 5-year incidence of DHEC is 10.3% and is associated with a favorable prognosis. Surgical repair of symptomatic or progressive DHEC is associated with an acceptable morbidity. However, the optimal surgical repair technique remains to be determined in view of the large number of recurrences.