[Positron emission tomography and stereotactic body radiation therapy for lung cancer: From treatment planning to response evaluation]. / TEP et radiothérapie stéréotaxique pulmonaire : rôles dans la préparation du traitement et le suivi de la maladie.

Stereotactic body radiation therapy is the standard treatment for inoperable patients with early-stage lung cancer. Local control rates range from 80 to 90 % 2 years after treatment. The role of positron emission tomography in patient selection is well known, but its use for target definition or therapeutic response evaluation is less clear. We reviewed the literature in order to assess the current state of knowledge in this area.

Comparison of positron emission tomography and lymphangiography in the diagnosis of infradiaphragmatic Hodgkin's disease.

PURPOSE: To evaluate the respective roles of positron emission tomography using 18F-fluorodeoxyglucose (FDG-PET) and lymphangiography (LAG) in staging Hodgkin's disease (HD) patients with negative contrast-enhanced infradiaphragmatic computed tomography (CT). MATERIAL AND METHODS: 28 patients underwent FDG-PET and LAG at initial staging. Concordant positive findings on both tests were regarded as actual HD locations and concordant negative findings as true negative. In case of discrepancy, the reference was biopsy or magnetic resonance imaging (MRI). RESULTS: Concordant results were obtained in 26 patients (24 negative, two positive). In two of the 24 negative patients, PET showed additional lesions in the spleen and one celiac lymph node (one patient), and in the right kidney and the right iliac crest (one patient). Discordant results were obtained in two patients. Both methods indicated infradiaphragmatic involvement in different locations in one patient. In the other, PET was falsely positive (PET done within 24 hours after a negative LAG), which was confirmed by biopsy (benign inflammatory, probably due to LAG medium). CONCLUSION: FDG-PET and LAG gave comparable results, making invasive LAG unnecessary. Furthermore, LAG, when performed before PET, can be responsible for false-positive PET results.

Interest of F-18 fluorodeoxyglucose positron emission tomography in the evaluation of vaginal malignant melanoma.

BACKGROUND: This is the first report of FDG-PET findings in a case of vaginal melanoma. CASE: The tumor arose from the anterior wall of the vaginal canal. As the tumor was limited to the vaginal wall and as there was no evidence of distant metastases, the disease was staged as IIC (AJCC 2002). PET-CT images showed two mediastinal foci localized to the left highest mediastinal and subcarinal nodes on fusion PET/CT images. As it was metastatic, the disease was staged IV (AJCC 2002). CONCLUSION: In comparison to conventional imaging, FDG-PET provides a more accurate assessment of the extent of disease spread in patients with vaginal melanoma as with cutaneous melanoma. Significant alterations in the surgical management and treatment were made based on PET results.