Positron emission tomography may improve lung cancer diagnosis

Tumor imaging with positron emission tomography (PET) may improve the diagnosis and subsequent treatment of lung cancer patients, according to a review published online November 27 in the Journal of the National Cancer Institute.

Tumor imaging is frequently used in the diagnosis of lung cancer and is important for making treatment decisions. Standard imaging technologies, such as magnetic resonance imaging or computed tomography imaging, provide information on anatomical changes, but PET imaging is based on biochemical processes that may detect disease even before anatomical changes occur. Therefore, PET imaging may complement standard imaging in the diagnosis of lung cancer.

To evaluate the accuracy of PET imaging, Yee Ung, M.D., of the Odette Cancer Centre in Toronto and colleagues reviewed several recent studies on PET imaging used for the diagnosis of lung cancer and for making treatment decisions. Their review was an update of a previous technology assessment conducted by the Toronto-based Institute for Clinical and Evaluative Sciences in 2001.

The researchers determined that PET imaging can accurately distinguish between benign and malignant tumors as small as 1 cm. There were limited data for the use of PET imaging in patients with small cell lung cancer, but the available data suggested that PET imaging is accurate in differentiating between extensive and limited disease. PET imaging appears to be better than computed tomography imaging for making treatment decisions for non–small-cell lung cancer patients. But the authors point out that further trials are still necessary to establish the clinical utility of PET imaging.

“Future research is needed to determine not only if PET should be integrated into the standard staging and diagnostic processes of lung cancer but also how PET would be incorporated into the staging algorithm,” the authors write.

In an accompanying editorial, Giuseppe Giaccone, M.D., of the National Cancer Institute in Bethesda, Md., discusses the recent improvements in imaging technology that must to be considered before determining the guidelines and recommendations for the use of PET imaging in lung cancer.

“[PET imaging] is being increasingly used in lung cancer and has acquired a relevant role in staging patients, assessing treatment strategies, and monitoring treatment effects. Although [PET] has not replaced more accurate and invasive procedures…improvements in the integration of [PET] with other imaging modalities are promising and likely to affect the management of patients with lung cancer in the future,” Giaccone writes.