425. PARACONDUIT HIATAL HERNIA FOLLOWING ESOPHAGECTOMY IN A PORTUGUESE TERTIARY CENTER

Abstract Background Esophageal Cancer is the seventh most common cancer worldwide with poor overall survival. As minimally invasive esophagectomy is becoming the new standard of care, an increased incidence of para-conduit hiatal hernias has been reported. Possible risk factors, other than those related to the operative approach have been suggested, such as location of the tumor. Histological type may also account for the increased incidence of hiatal hernias due to shift from esophageal squamous cell carcinomas to adenocarcinomas of the gastro-esophageal junction in Western world. We reviewed our center’s experience to determine whether the adoption of minimally invasive esophagectomy was associated with an increased incidence of para-conduit hernia. Methods A single-center, prospective database was used to retrospectively analyze consecutive patient who underwent esophagectomy between January 2007 and December 2023. Results Between January 2007 and December 2023, 497 patients were submitted to esophagectomy (Ivor-Lewis, McKeown or transhiatal) due to cancer (242 squamous cell carcinomas and 255 adenocarcinomas); 163 proximal esophageal cancers and 323 distal esophageal cancers. An hiatal hernia was diagnosed in 11 (2.21%) of 497 included patients submitted to esophagectomy; 5 (3.25%) after 154 totally minimally invasive esophagectomies, 3 (11.11%) after 27 hybrid esophagectomies and 3 (0.95%) after 316 open esophagectomies. The median days to diagnosis of hiatal hernia was 199 (6-3881) days. Surgical treatment consisted of cruroplasty in 1 patient, crurorrhaphy in 6 patients, reduction of herniated contents in 4 patients. The tumor was located proximally in 1 patient whereas the remaining 10 were at distal esophagus or at gastro-esophageal junction. Regarding pathologic evaluation, 2 were squamous cell carcinomas (0.82%) and 9 adenocarcinomas (3.53%). Conclusion In our experience, the adoption of minimally invasive esophagectomy has been associated with an increase of symptomatic para-conduit hernia, in line with the reports of recent meta-analyses. The prevalence of paraconduit hiatal hernia was also increased in adenocarcinomas, revealing the shift in the histological type in Western world. The true rate of herniation may be much higher, as our patients are not routinely submitted imaging diagnostic tests as part of their follow-up.