Danish scientists have identified which head and neck cancer patients will benefit from additional drug treatment during radiotherapy, in a paper published online today by The Lancet Oncology.
Tumours that have low concentrations of oxygen (hypoxia) are resistant to radiotherapy. A drug called nimorazole (a hypoxia radiosensitiser) can improve the outcome of radiotherapy for patients with these types of tumours. However, at the moment there is no way to identify people with tumours that lack oxygen, who need this additional drug treatment, from those that only need radiotherapy.
Researchers knew that the concentration of a protein called osteopontin was associated with tumours that lacked oxygen. Jens Overgaard (Aarhus University Hospital, Denmark) and colleagues assessed whether blood concentration of osteopontin could predict patients’ responses to nimorazole. The investigators measured the concentration of osteopontin in 320 patients on a trial comparing nimorazole and radiotherapy with placebo and radiotherapy. Patients were grouped into high, intermediate, and low concentrations of osteopontin and the team recorded their outcome. They found that patients with high concentrations of the protein assigned placebo had a poorer prognosis than those with high concentrations on nimorazole.
Professor Overgaard states: “. . . high plasma concentration of osteopontin predicted clinically relevant, modifiable hypoxia-induced resistance to radiotherapy, and this finding might help to identify patients who will benefit from treatment with a hypoxia modifier such as nimorazole during radiotherapy. By contrast, use of nimorazole was not effective in patients with low or intermediate plasma concentrations of osteopontin.”