Although the definitive role of surgery in metastatic disease has not been established, conservative resections of the intestine, mesenteric tumors, and fibrotic areas may improve symptoms and quality of life substantially in patients with metastatic hepatic, mesenteric, and peritoneal carcinoids. If the condition of the patient is such that surgery is not a greater risk than the disease, the primary tumor should be resected to prevent an emergency presentation with obstruction, perforation, or bleeding. Despite common acceptance that resection of at least 90% of the tumor burden is required to achieve palliation, approximately 60% of patients with surgery alone will experience symptom recurrence; the 5-year survival rate is between 35% and 80%, depending on the experience of the surgical center.[2,3] Because treatment with somatostatin analogs can achieve similar rates of symptom relief with fewer adverse effects, in each patient the benefits of surgical treatment of gastrointestinal (GI) carcinoid tumors should be weighed carefully against the potential risks of an open exploration. Tumor debulking, however, may potentiate pharmacologic therapy by decreasing the secretion of bioactive substances.
Management of hepatic metastases may include surgical resection; hepatic artery embolization; cryoablation and radiofrequency ablation; and orthotopic liver transplantation. (Refer to the Treatment of Hepatic Metastases section of the Treatment Option Overview section of this summary for more information.) Cytoreductive surgery for hepatic metastases from GI carcinoids can be performed safely with minimal morbidity and mortality resulting in regression of symptoms and prolonged survival in most patients. In one large review that included 120 carcinoid patients, a biochemical response rate of 96% and a 5-year survival rate of 61% were reported for patients whose hepatic metastases were resected surgically.[Level of evidence: 3iiDii]
Newcastle disease virus (NDV) is a virus that is of interest because it replicates (makes copies of itself) more quickly in human cancer cells than in most normal human cells and because it can kill these host cells (see Question 1).
NDV can be used to directly kill cancer cells, or it can be given as a cancervaccine. Cancer vaccines cause the body's natural immune system to seek out and destroy cancer cells (see Question 4).
The results of clinical trials (research studies with people)...
In the case of liver metastases, localization and resection of the primary tumor may be considered, even among patients in whom the primary neoplasm is asymptomatic. In a retrospective study involving 84 patients, 60 of whom had their primary neoplasm resected, the resected group had a greater median progression-free survival (PFS) of 56 months, compared with 25 months of PFS for the primary nonresected group (P < .001). Median survival time for the resected group was longer at 159 months when compared with 47 months for the nonresected group (P < .001).[Level of evidence: 3iiDii ]