A self-made cure for lung cancer?

A lung cancer vaccine using the patient's own tumour cells shows limited promise after phase II trials. Could this be the future of treatment?

By Graham Furness

Don't tell any friends who are smokers, but a new lung cancer vaccine has just finished phase I/II trials with reasonably promising results. Reasonably promising, that is, when measured against the appallingly low expectations of survival associated with this lethal disease.

A small number of the patients participating in this trial have survived three years since beginning treatment, even though they had advanced disease at the outset. Connie West of Waxahachie, TX is one of those lucky few. She had stage IV cancer and began taking the vaccine in 2001. "I had cancer in both lungs," she said, "and it just gradually went away. I had a scan last week, and there's no sign of cancer in my body. It's almost unbelievable."

Scientists from the Baylor University Medical Centre, Dallas, TX created each patient's vaccine individually using cells from their tumours, which were surgically removed. A gene called GM-CSF was placed into the cancer cells to change their surface markers, permitting the immune system to identify them as cancerous. The research was published in the Journal of the National Cancer Institute.

The researchers vaccinated 43 patients who had non-small cell lung cancer. Ten had early stage disease and 33 had advanced stage disease. The patients were injected with the vaccine every fortnight, receiving a total of between three and six shots over a period of a few months.

Vaccines that secreted the most GM-CSF gave the best results. Patients receiving these stronger vaccines had a median survival of 17 months, compared to seven months in those getting vaccines with lower secretions of GM-CSF. Three patients had complete tumour responses, lasting six months, 18 months and in one case still responding 22 months later. Two of these patients had bronchioloalveolar tumours, a subtype of the non-small cell lung cancer group, adenocarcinomas. In others, the vaccine appeared to delay the recurrence of cancer for several months. Curiously, the vaccine didn't appear to have any benefit for patients with early stage lung cancer.

Non-small cell lung cancer kills around 14,000 Canadians a year. Only about one patient in five is a candidate for surgery; chemotherapy and radiotherapy are the current standard treatments.

Dr John Nemunaitis, who led the research, is cautiously hopeful about the future of the vaccine. "I can't say this is a cure," he said. "But in a small number of people sensitive to this approach, the cancer hasn't come back -- for over three years and counting for a number of patients."