High dose chemotherapy along with stem cell transplantation has been shown to be more effective than standard treatment for myeloma patients under age 65. The study, which appears in the New England Journal of Medicine (Vol. 348, No. 19: 1875-1883), found that this treatment added nearly one year of life.

Multiple myeloma is a cancer of bone marrow cells that affects mainly people in their 60s and 70s. Nearly 15,000 people will be diagnosed with this cancer in the US in 2003. Chemotherapy can be effective, but half of patients die of this cancer within three years. This survival rate hasn’t changed for many years.

In the last 10 years, treatment with high dose chemotherapy and stem cell rescue (transplantation) has been frequently used, particularly in younger patients. But it hasn’t been clear that this is better than treatment with conventional doses of chemotherapy. Only one study that compares conventional with high dose chemotherapy has been published. That study of 200 patients, published in 1996, showed a benefit for the high dose treatment.

This British study confirms the original results.

Beginning in 1993, researchers from the University of Leeds and other centers enrolled just over 400 patients, all under 65 years of age. Half received conventional chemotherapy and the other half received the high dose treatment. Along with the high doses of chemotherapy, they also received infusions of bone marrow stem cells that had been collected from their blood. These stem cells are needed to replace the bone marrow cells that are destroyed by the high doses of chemotherapy.

Those receiving the high dose treatment were much more likely to have a remission of their myeloma (44% versus 8% of patients on standard treatment). It also took longer, on average, for their cancer to return after treatment (32 months versus 20 months); and the median survival was prolonged from 42 months in the conventionally treated group to 54 months in the high dose patients. Median survival is the point at which half the patients have died.

Another positive finding from this study is that patients who had the worst prognosis got the most benefit out of the high dose treatment. But a shortfall of the study is that it was confined to patients under age 65, while about two-thirds of all patients with myeloma are over 65.

This doesn’t mean that high dose chemotherapy and stem cell rescue can’t be given to patients older than 65. Patients over 65 are receiving this treatment in the US; it just hasn’t been proven that this is better than conventional treatment for this age group.