New cancer treatment significantly reduces tumour progression and death

A new approach for early cancer treatment known as radioligand therapy has been shown to reduce the risk of advanced neuroendocrine tumour progression and death by 72 per cent in otherwise challenging areas to treat. 

The results from the multi-centre clinical trial, led by scientists at Sunnybrook Health Sciences Centre and the University of Toronto, were published this week in The Lancet.

“Cancer care has traditionally been treated by surgery, drugs or radiation; RLT is a game changer in the practice of cancer treatment. While it’s technically radiation, it is given via a chemotherapy route through the blood until it reaches the precise location of the tumour,” says Simron Singh, global principal investigator on the trial, who is a medical oncologist at Sunnybrook and an associate professor of medicine at U of T’s Temerty Faculty of Medicine.

Results from the NETTER-2 Phase III international clinical trial provided evidence for the first time that RLT — when applied in the early stages after a patient’s diagnosis — significantly and safely slowed down the progression of aggressive higher Grade 2 and 3 neuroendocrine tumour growth (of the gastrointestinal tract), extending the average time of “progression-free survival” from approximately 8.5 months to 22.8 months. 

“This is the first study to show the effectiveness of RLT as the ‘first-line’ treatment with advanced uncurable cancer, or any cancer,” says Singh, who is also an affiliate scientist at Sunnybrook Research Institute and cofounder of the Susan Leslie Clinic for Neuroendocrine Tumours at Sunnybrook’s Odette Cancer Centre. “This trial is groundbreaking not only for patients with neuroendocrine cancers, but for all cancer patients as it has implications for the practice of cancer treatment broadly.”

Radioligand therapy involves injecting radioactive isotopes through an IV (in this case, with the drug known as Lutathera) in order to target specific cancer cell receptors, and deliver more targeted and precise radiation to kill cancer cells while preserving healthy tissue. 

This study evaluated the use of RLT earlier as a first-line (or “up front”) treatment for patients newly diagnosed with grade 2 or 3 advanced gastrointestinal neuroendocrine tumours. Although neuroendocrine cancer is uncommon, its incidence is rising rapidly, and few treatments exist for patients. This cancer is resistant to most therapies, making it challenging to treat.

“The results confirm the clinical benefit of earlier use of RLT for newly diagnosed patients with these types of aggressive and life-threatening tumours,” says Singh. “This is the next step in personalized targeted cancer therapy for patients, focused on more effectively killing cancer cells, while limiting the damage to surrounding healthy tissues.”

Further investigations of RLT as a therapeutic option are ongoing to evaluate overall survival and long-term safety, which will better define next steps for how this therapy will change cancer treatment world-wide.

The multi-site trial included investigators and participants from Canada, France, Germany, Italy, Netherlands, South Korea, Spain, UK and USA. An overview of the results was presented at the 2024 American Society of Clinical Oncology (ASCO) Gastrointestinal (GI) Cancers Symposium in January 2024.