Textural analysis of baseline F-FDG PET/CT provides strong independent predictors of survival in patients with LARC, with better predictive power than intensity- and volume-based parameters. The utility of such features, especially coarseness, should be confirmed by larger clinical studies before considering their potential integration into decisional algorithms aimed at personalized medicine.

Abstract. Despite advances in morphological imaging, some patients with lung cancer are found to have non resectable disease at surgery or die of recurrence within a year of surgery. At present, metastatic bone involvement is usually assessed using bone scintigraphy, which has a high sensitivity but a poor specificity. We have attempted to evaluate the utility of the fluorine-18 deoxyglucose positron emission tomography (FDG PET) for the detection of bone metastasis. One hundred and ten consecutive patients with histological diagnosis of non-small cell lung cancer (NSCLC) who underwent both FDG PET and bone scintigraphy were selected for this review. In this group, there were 43 patients with metastatic disease (stage IV). Among these, 21 (19% of total group) had one or several bone metastases confirmed by biopsy (n = 8) or radiographic techniques (n = 13). Radionuclide bone scanning correctly identified 54 out of 89 cases without osseous involvement and 19 out of 21 osseous involvements. On the other hand, FDG PET correctly identified the absence of osseous involvement in 87 out of 89 patients and the presence of bone metastasis in 19 out of 21 patients. Thus using PET there were two false-negative and two false-positive cases. PET and bone scanning had, respectively, an accuracy of 96% and 66% in the evaluation of osseous involvement in patients with NSCLC. In conclusion, our data suggest that whole-body FDG PET may be useful in detecting bone metastases in patients with known NSCLC.

In order to evaluate the usefulness of 18-fluorodeoxyglucose (FDG) positron emission tomography (PET) in the assessment of therapeutic effects, a study was performed before and after therapy in 126 patients with non-small cell lung cancer (NSCLC) codified stage I to stage IIIB.Treatment with an early curative result was given in 58 patients, whereas in 68 cases it was limited to palliation. During the treatment follow-up period (8±40 months), each patient was evaluated every 3 months by clinical examination and #6 months by imaging techniques (PET and computed tomography (CT)).A diagnosis of persistent or recurrent tumour was established by means of pathological analysis in 31 patients and by clinical evolution and subsequent imaging progression in 29 other patients. PET showed increased FDG uptake in all cases (n=60) of persistent or recurrent tumour, whereas CT was nonspecific in 17 cases. Conversely, there were five false positive cases via PET imaging and three via CT. In detecting residual or recurrent NSCLC, PET had a sensitivity of 100% and specificity of 92%, whereas CT had a sensitivity and specificity of 71% and 95% respectively.In conclusion, 18-fluorodeoxyglucose positron emission tomography correctly identified response to therapy in 96% (121 of 126) of patients. Positron emission tomography appears to be more accurate (p=0.05) than conventional imaging in distinguishing persistent or recurrent tumour from fibrotic scar in patients undergoing treatment for non-small cell lung cancer. Eur Respir J 1999; 14: 1376±1380.

The aim of this study was to evaluate the clinical performances of whole body 2-[18F]fluorodeoxyglucose positron emission tomography (FDG PET) imaging for the detection of the primary tumour in patients with metastases of unknown origin. Forty-one patients, without previous history of known cancer (18 women and 23 men; average age 64.1 years) with metastasis confirmed by histopathological analysis were included in a retrospective study. Results of PET were compared with those of techniques used in the current conventional diagnostic procedure. All known metastatic lesions were detected by PET. There were 26 true-positive and two false-negative results. Primary tumour remained undetermined in eight patients after conventional investigations and PET. PET was superior to conventional diagnostic procedure in 11 patients and led to modify treatment in 11 patients. Sensitivity of PET was superior than computed tomography in detecting abdominal primary tumours. FDG PET is useful in patients with unknown primary tumour because its sensitivity is good and it could modify the disease management. Otherwise, PET allows the evaluation of the extent of the disease and could be used to monitor treatment efficiency. Its contribution has to be evaluated particularly in patients with primary tumour with a specific treatment.