Researchers report the results of a new analysis from a phase III trial of patients with neuroendocrine tumours that begin in the gastrointestinal (GI) tract or have an unknown origin.

Compared to placebo, everolimus was associated with a six- to eight-month longer time period before the cancer worsened.

The study was presented at the 2016 Gastrointestinal Cancers Symposium in San Francisco.

“Everolimus has the potential to stop the cancer from growing for a prolonged period of time,” said lead study author Simron Singh, MD, MPH, FRCP(C), a medical oncologist at Sunnybrook’s Odette Cancer Centre in Toronto, Canada.

The analysis included 175 patients with previously treated, advanced GI neuroendocrine tumours and 36 patients with neuroendocrine tumours of an unknown site of origin. All patients had non-functional tumours, meaning that the tumour caused few or no symptoms initially.

“In consultation with their oncologist, patients with neuroendocrine tumours may consider this as one of the new standard treatment options,” said Dr Singh.

Study patients were randomly assigned to receive everolimus plus best supportive care, or placebo plus best supportive care.

All patients had tumours that progressed on other therapies, which included somatostatin analog (a standard hormone therapy for neuroendocrine tumours), surgery, or chemotherapy.

Overall, everolimus reduced the risk of disease progression by about 40% compared to placebo.

Among patients with GI neuroendocrine tumours, the median progression-free survival was 13.1 months with everolimus vs. 5.4 months with placebo.

In the group of patients with tumour of unknown origin, the median progression-free survival with everolimus and placebo was 13.6 and 7.5 months, respectively.

The most common adverse events in the everolimus arm were stomatitis (inflammation of the mouth), infections, diarrhoea, peripheral edema, and fatigue.

Neuroendocrine tumours are a group of cancers that begin in hormone-producing (neuroendocrine) cells of various organs in the body.

Most neuroendocrine tumours begin in the GI tract.

While they are uncommon (each year only about 8,000 people in the United States are diagnosed with a neuroendocrine tumour of the gastrointestinal tract), the incidence of neuroendocrine tumours is on the rise.

“Currently there are limited treatment options for patients with GI neuroendocrine tumours, so this study is a welcome advancement in the field, opening the door to a new exciting treatment,” say Dr Singh.

Everolimus has previously been approved for the treatment of pancreatic neuroendocrine cancer.

Source: ASCO