PET Scans Provide Key Info on Cancer Stage, Treatment Progress, Says Study

PET (positron-emission tomography) and the combination of PET and CT (in one instrument) help physicians determine the stage of a patient's cancer, how well it has responded to treatment, and whether it has re-appeared again after treatment, according to the study. This information helps physicians better determine next steps in treatment—often allowing patients to avoid unneeded treatment.

• PET is currently approved for restaging—or detecting whether the cancer has returned or remains after treatment—for breast, colorectal, esophageal, head and neck, non-small-cell lung, and certain recurrent thyroid cancers, as well as melanoma and lymphoma. It is especially useful in distinguishing between new tumors that have developed and the scar tissue that is left over from earlier treatment. This helps avoid unnecessary treatment when no cancer is truly present or, if the cancer has returned, enables new therapy to begin promptly.

• Though PET is relatively expensive in the United States, according to the study, it also offers clear opportunities for savings. One study found that restaging colorectal cancer patients with PET resulted in a 4-to-1 net savings-to-cost ratio, largely because PET enabled physicians to identify patients with inoperable disease who would not benefit from surgery. Studies also indicate that restaging with PET may help patients with head and neck cancer avoid potentially disfiguring neck surgery.

1. Juweid, M.E. and B.D. Cheson. "Positron-Emission Tomography and Assessment of Cancer Therapy," The New England Journal of Medicine, February 2, 2006, 496 – 507.