[Positron emission-computed tomography in diagnosis and staging of lung neoplasms. Personal experience]

Background. Positron emission-computed tomography (PET) scans are obtained from the accumulation of a radiotracer in tissues with altered metabolism, such as malignant neoplasms. The authors present their experience with PET, performed in 50 selected patients with lung neoplasms in the 1998-2000 period. Methods. The indications to PET corresponded to those most frequently reported in the literature, that is: diagnosis in solitary pulmonary nodule 8 patients; mediastinal lymph node staging, 16 patients; re-evaluation after neo-adjuvant therapy, 21 patients; increased markers blood levels in the follow-up of resected patients, 5 cases. Each indication is individually discussed and compared with the data of the literature, especially regarding the role of PET and its relationship with other noninvasive and invasive diagnostic tools. Results. In 47 patients (94%) diagnostic yield was reached. A false positive (acute inflammatory lesion in solitary pulmonary nodule), a false negative (no demonstration of lymphangitic intrathoracic recurrence) and a non-diagnostic result (then pathologically proved non-neoplastic) were recorded. Conclusions. Thus the authors consider PET extremaly useful in the diagnosis and staging of lung neoplasms; the high cost of PET may be compensated for the reduced need for invasive diagnostic tools and, avoiding inappropriate surgical options, with favourable cost-effectiveness.Thus, PET may be indicated in most, if not in all, patients with lung neoplasms.