Still, information about the risks faced by a patient could help doctors make choices about treatments, said Minna, who called the test "promising."
Study co-author Mann agreed: "There may be an important conversation that you can have with your oncologist about potential benefit from additional therapy to reduce the likelihood of the cancer coming back."
Mann said the test -- which is currently available -- could cost several thousand dollars. Minna, the commentary co-author, said any cost over a few hundred dollars could be an issue for insurors.
The research was funded by the firm that developed the molecular test, and several of the study authors serve as consultants to the firm.
The study appears in the Jan. 27 online issue of The Lancet.
For more about lung cancer, try the U.S. National Library of Medicine.
SOURCES: Michael J. Mann, M.D., associate professor, surgery, University of California, San Francisco; John D. Minna, M.D., professor, medicine, University of Texas Southwestern Medical Center, Dallas; Jan. 27, 2012, The Lancet
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