|Lymphochip predicts success of chemotherapy in cancer patients|
By Kate Dalke
June 21, 2002
Patterns of gene expression in tumor cells can be used to predict whether lymphoma patients will benefit from chemotherapy, according to a new study. The researchers identified as few as seventeen genes that can help doctors recommend whether individuals should undergo chemotherapy.
Among patients with diffuse large B-cell lymphoma, less than half respond well to chemotherapy. New methods are needed to develop accurate prognoses for patients with lymphoma cancer, a non-Hodgkin's form of the disease that attacks cells in the lymphatic system and can spread anywhere in the body.
"Our outcome predictor may help identify patients who are unlikely to be cured by conventional therapy," the authors write in The New England Journal of Medicine. For these patients there are alternative treatments such as bone marrow transplantation and therapies that target cellular pathways, which may block a person's response to chemotherapy.
The researchers used the Lymphochipa gene chip specialized for lymphoid cellsto analyze tumor biopsies from 240 cancer patients. They analyzed thousands of genes and identified seventeen genes that could be used to create a larger molecular predictor of patient survival. On the basis of this predictor, they found that one quarter of the 240 individuals comprised a risk group with a five-year survival rate of 15 percent.
The new predictor differs from the international prognostic index doctors currently use to make recommendations about treatment options. This prognostic index includes clinical factors such as a patient's age, the stage of the tumor and how far the disease has spread. Scientists note that this technique has advantages, but that it has not been a good predictor of patients who should seek alternative therapies.
The study "highlights the need to use molecular diagnosis in patients," the authors write. These diagnoses will help develop individualized and molecularly targeted drugs, they add.
The research was led by Louis M. Staudt of the National Cancer Institute in Bethesda, Maryland, and includes research institutions from both the United States and abroad. The study is part of NCI's Lymphoma/Leukemia Molecular Profiling Project, a project in which scientists are using gene chips to define gene expression profiles in lymphoid tumors and then develop therapies to target them.
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