Positron emission tomography (PET) is a non-invasive imaging procedure used to assess metabolic activity and perfusion in various organs or tissues in the human body. Images are obtained by processing of emissions from positron-emitting radioisotopes that are usually administered intravenously. The radioisotope commonly used in oncologic PET imaging procedures is 2-[F18] fluoro-2-deoxy-D-glucose (FDG).

The rate of FDG decay provides information on glucose metabolism of tissues being studied. As malignancies can cause abnormalities of glucose metabolism, FDG PET evaluation can indicate the probable presence or absence of malignancy based upon observed differences in biologic activity as indicated by the glucose metabolism of adjacent tissues.

Section 220.6.17 of the National Coverage Determination (NCD) Manual establishes coverage for only one FDG PET scan for guiding initial antitumor treatment strategy for beneficiaries who have solid tumors and myeloma that are biopsy proven or strongly suspected of being cancer based on other diagnostic testing, when the beneficiary's treating physician determines that the FDG PET study is needed to determine the location and/or extent of tumor for various therapeutic purposes.

The requestors have asked CMS to reconsider Section 220.6.17 to remove the restriction that only one FDG PET scan may be performed as part of guiding the initial antitumor treatment strategy.