Genes may show which lung cancer patients need aggressive care

WASHINGTON -- Studying the genes active in early stage lung cancers may help identify which patients are at greatest risk of dying, allowing their doctors to prescribe more aggressive treatment, researchers report.

A team led by Dr. David G. Beer at the University of Michigan found that by studying which of about 50 genes in an early stage tumor are more or less active, it could predict which patients are more likely to relapse within five years.

With that information, doctors would know which patients should get additional treatment, perhaps adding radiation or chemotherapy to the standard of surgery, Beer said.

The study is in Monday's online edition of the journal Nature Medicine.

Identifying high-risk patients through their genes is still experimental, Beer said. But he said the process has the potential to help doctors provide more individualized care for their patients.

"This study of gene expression profiling in lung cancer is a valuable contribution to the exciting area of molecular cancer characterization," said Dr. Daniel R. Jacobson of the New York University School of Medicine.

Jacobson, who was not connected to the Michigan team, said cancer physicians long have sought ways to predict a patient's long-term prospects.

"While it would be premature to make decisions about postoperative chemotherapy or radiotherapy based on gene expression profiling, the field is moving in that direction," he said.

Profiling as a tool

Some day, perhaps soon, such profiling probably will become a standard tool to help doctors decide on treatment, Jacobson added.

Already, an additional drug is being offered to breast cancer patients who have extra copies of a gene that makes their tumors more aggressive.

The Michigan study focused on patients with stage 1 lung cancer, the earliest form of the disease.

Of 169,400 new lung cancer cases expected to be diagnosed in the United States this year, only about 15 percent will be caught at that early stage, the American Cancer Society says.

Of those stage 1 patients who have surgery to remove the tumor, between 35 percent and 50 percent suffer a return of the disease within five years, Beer said.

The researchers studied lung tissues from cancer patients, compared their gene profiles with the long-term outcome, and concluded that the activity or inactivity of certain genes was related to which patients were most at risk for relapse.

They developed a risk index of about 50 genes and then turned to a different set of tumors collected in a study at Harvard University, Beer said. The risk index was able to predict survival among the patients in that study, he said.

But he said more study is needed before the risk index could come into regular use.

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