No evidence from randomised clinical trial for optimal management of resectable liver spread originating from intestinal hormone cells

Liver spread from hormone-producing cancer of intestinal hormone cells is generally treated by liver resection surgery (removing the affected parts of the liver) if it is possible to remove all the cancer deposits and is associated with good long-term survival. However, recently, destroying the tumour using radiofrequency waves has been reported to show reasonably good survival in patients in whom it is not possible to remove the liver spread by surgery. This Cochrane review attempted to answer the question whether surgical resection of the liver tumours is better than other forms of treatment in patients with removable liver spread. We could not find any randomised clinical trials addressing the issue. Currently, there is no evidence from randomised clinical trials comparing liver resection versus other treatments in patients with resectable liver spread originating from intestinal hormone cells. Evidence from retrospective studies has shown prolonged survival after surgery for such patients. There has also been some suggestion that combining treatments such as surgery and chemotherapy or radioactive tracer treatment results in better survival than surgery alone. Therapies such as radiofrequency ablation (heat destruction of the tumours using radiofrequency waves) have been recently evaluated as curative treatment and may be useful in patients with small tumours (smaller than 5 cm in size). However, long-term follow-up data from radiofrequency ablation is not available. Liver resection appears to be the main stay curative treatment for neuroendocrine liver metastases based on non-randomised studies. Further randomised clinical trials comparing liver resection alone or in combination with chemoembolisation or radionuclide therapy are needed. Further randomised clinical trials comparing liver resection and radiofrequency ablation in selected patients may also be appropriate.

Authors' conclusions: 

There is no evidence from randomised clinical trials comparing liver resection versus other treatments in patients with resectable liver metastases from gastro-entero-pancreatic neuroendocrine tumours. Liver resection appears to be the main stay curative treatment for neuroendocrine liver metastases based on non-randomised studies. Further randomised clinical trials comparing liver resection alone or in combination with chemoembolisation or radionuclide therapy are needed. Further randomised clinical trials comparing surgical resection and radiofrequency ablation in selected patients may also be appropriate.

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Background: 

Neuroendocrine tumours are tumours of cells, which possess secretory granules and originate from the neuroectoderm. While liver resection is generally advocated in patients with resectable liver metastases, recent studies have shown good survival in patients with disseminated neuroendocrine tumours who underwent thermal ablation using radiofrequency.

Objectives: 

To determine the benefits and harms of liver resection versus other treatments in patients with resectable liver metastases from gastro-entero-pancreatic neuroendocrine tumours.

Search strategy: 

We searched The Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE, Science Citation Index Expanded and LILACS until July 2008 for identifying the randomised trials.

Selection criteria: 

We considered only randomised clinical trials (irrespective of language, blinding, or publication status) comparing liver resection (alone or in combination with radiofrequency ablation or cryoablation) versus other interventions (chemotherapy, hormonotherapy, or immunotherapy) and those comparing liver resection and thermal ablation (radiofrequency ablation or cryoablation) in patients with resectable liver metastases from neuroendocrine tumours for the review.

Data collection and analysis: 

Two authors independently identified trials for inclusion.

Main results: 

We were unable to identify any randomised clinical trial suitable for inclusion in this review. We were also unable to identify any quasi-randomised studies, cohort studies, or case-control studies that could inform meaningfully.