Selective internal radiation therapy for neuroendocrine tumours that have metastasised to the liver

NICE did a rapid review of the published literature on the efficacy and safety of this procedure. This comprised a comprehensive literature search and detailed review of the evidence from 9 studies reported in 8 publications, which was discussed by the committee. The evidence included 2 systematic reviews and meta-analyses, a large retrospective comparative study, an analysis of international registry data, a small single-arm trial, a retrospective analysis of a small, prospective, UK-based study and 2 retrospective case series. It is presented in the summary of key evidence section in the interventional procedures overview. Other relevant literature is in the appendix of the overview.

The professional experts and the committee considered the key efficacy outcomes to be:

• quality of life

• tumour control in the liver

• symptom response

• overall survival

• hepatic progression-free survival.

The professional experts and the committee considered the key safety outcomes to be:

• mortality

• radiation-induced liver disease

• post-radioembolisation syndrome

• other clinical toxicity

• other biochemical toxicity.

For auditing the outcomes of this procedure, the key outcomes identified in this guidance can be entered into NICE's interventional procedure outcomes audit tool (for use at local discretion), with details of patient selection. This will help to define which people will benefit most from SIRT.

One commentary from a person who has had this procedure was discussed by the committee. They had side effects including tiredness, nausea and weight loss. The worst of the side effects lasted 4 to 6 weeks. They remain tired and nauseous 2 months after treatment and have started to regain weight. They said that the procedure has stopped almost all the carcinoid syndrome symptoms. They have been able to return to their normal activities, which has improved their mental health.

Experts emphasised that selective internal radiation therapy (SIRT) may be particularly useful for people with large metastatic neuroendocrine tumours who have symptoms of carcinoid syndrome.

When appropriate, SIRT can be preceded or followed by other treatments including peptide receptor radionuclide therapy, and it can be repeated. In some people, SIRT can open options for alternative treatment afterwards.

Neuroendocrine tumours that have metastasised to the liver may be more suitable for SIRT than other types of tumour in the liver, because they are usually hypervascular.

SIRT is likely to be better tolerated than other intra-arterial therapies, because SIRT relies on radiation rather than embolic effect to kill the tumour cells.

Clinical experts informed the committee that dosimetry methods are evolving.