Management of Neuroendocrine Tumor–Related Fibrosis

Bowel obstruction secondary to peritoneal fibrosis is the most common presenting symptom of small intestinal neuroendocrine tumors. Heart failure secondary to right-sided valvular fibrosis represents a serious extraintestinal manifestation of neuroendocrine tumor–related fibrosis. It occurs in 20% to 70% of patients with metastatic disease and it accounts for as much as 50% of neuroendocrine tumor mortality.[28,29] There is no effective pharmacological therapy for either clinical problem. In the instance of bowel obstruction, surgical lysis of the adhesions often is technically demanding because of the cocoon-like effects of extensive fibrosis stimulated by the various tumor-derived growth factors.[30] Valvular replacement usually is required to manage carcinoid heart disease.[1]