Enterovascular Fistula: An Under-Recognized Complication Related to Therapy for Esophageal Carcinoma

The formation of a fistula between the gastrointestinal tract and cardiovascular system is a rare but devastating condition. Although clinical diagnosis is suspected, autopsy confirmation is rarely obtained. Advancement in the treatment of esophageal cancer could result in an increased risk of enterovascular fistula formation. We describe autopsy-proven series of enterovascular fistulas with particular focus on this complication developing as a consequence of esophageal cancer therapy. Cases of enterovascular fistulas were retrospectively identified in the institutional autopsy case records (1994-2017). Relevant clinical information and pathologic findings were reviewed. Nine cases were identified. Seven out of 9 were related to malignancy, with 6/9 occurring in the setting of treated esophageal carcinoma. This esophageal cancer group was a unique set of patients (age median: 71 years) with male predominance (M:F-5:1) presenting with hematemesis as the main symptom. All patients had advanced disease at diagnosis and the complication generally occurred late after treatment (mean interval: 1.7 years). The fistula site was between the esophagus and variety of vascular structures. The most common etiology was tumor invasion (4/6). The diagnosis of enterovascular fistula was made postmortem in all cases. The development of enterovascular fistulas is a late complication of treated esophageal cancer. Tumor invasion, infection, and radiation response are the leading etiologies. Early recognition and aggressive treatment may salvage this highly morbid complication.