Positron Emission Tomography (PET) is a functional imaging method frequently used to assess diagnosis and prognosis of patients with cancer. PET main clinical application are staging and restaging tumors, and the evaluation of treatment. Furthermore, in lung cancer, PET has been used to assess malignancy of solitary pulmonary nodules, that are undetermined at conventional imaging (e.g. Computed Tomography , CT).
This study is the first one published showing PET usefulness for lung cancer screening. The study, that includes 1035 subjects at high risk for lung cancer (heavy smokers), shows that PET scanning performed in all CT undetermined nodules, is able to provide a diagnosis in 43% of them.
Research field:
This study is a classical example of Molecular Medicine, as it uses a Molecular Imaging method, i.e. PET with [18F]FDG, that allows the characterisation and measurement of an important biological process (glucose metabolism) at the cellular level. Like its analogue, glucose, FDG is largely utilised by neoplastic cells for their rapid proliferation, via the same membrane transporter (GLUT) and the same enzymes (Hexokinase).
Clinical applications:
The results of this work are very important to the National Health System, as they suggest a new strategy for lung cancer screening programmes. In fact, a PET study performed after CT in those cases that remain undetermined, allows the reduction of either invasive diagnostic procedures (usually suggested in these cases) or a 'wait and see' decision that might prevent from curative surgery.
Collaborations:
Collaboration are foreseen with clinical oncologist and surgeons for the diagnosis and screening of lung cancer. Furthermore, a collaboration with molecular biologists is ongoing, in order to better understand [18F]FDG mechanisms of uptake in neoplastic cells.
Future developments:
The present work reports the results obtained in the first 2 years of a 5 years study.
To evaluate the clinical impact of CT and PET in screening lung cancer, another trial on 10.000 expected cases of subjects at risks for lung cancer has started in 10-15 Italian Centres. All PET data will be supervised by our Center.
The results of this work have been published on Lancet: Early lung-cancer detection with spiral CT and positron emission tomography in heavy smokers: 2-year results. Pastorino U, Bellomi M, Landoni C, De Fiori E, Arnaldi P, Picchio M, Pelosi G, Boyle P, Fazio F. Lancet. 2003 Aug 23;362(9384):593-7.
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