PET Scan and CT Scan in Evaluating Response in Patients Undergoing Radiofrequency Ablation for Lung Metastases (TEPARF)

PET Scan and CT Scan in Evaluating Response in Patients Undergoing Radiofrequency Ablation for Lung Metastases

Study of Positron Emission Tomography/CT Scan for Response Evaluation After Radiofrequency Ablation in Patients With Lung Metastases

RATIONALE: Radiofrequency ablation uses a high-frequency, electric current to kill tumor cells. Diagnostic procedures, such as PET scan and CT scan, may help doctors measure the patient's response to treatment. PURPOSE: This clinical trial is studying PET scan and CT scan to see how well they work in evaluating response to treatment in patients undergoing radiofrequency ablation for lung metastases.

OBJECTIVES: Primary Determine the accuracy of positron emission tomography (PET) and CT scan in measuring response at 3 months after radiofrequency ablation (RFA) in patients with lung metastases. Secondary Determine the agreement between observers analyzing PET/CT scan results. Determine the outcome of these patients. Determine the false-positive rate and false-negative rate of PET/CT scan at 1 and 3 months in these patients. Determine the optimal time for obtaining a negative PET scan. Determine the sensitivity, specificity, positive predictive value, and negative predictive value of PET/CT scan at 1 and 3 months. Determine the morbidity associated with RFA. Determine the disease-free survival after RFA and the factors predicting recurrent disease in these patients. OUTLINE: This is a multicenter study. Patients undergo positron emission tomography (PET) and CT scan at baseline. Patients then undergo radiofrequency ablation (RFA) for lung metastases. PET/CT scan is repeated at 1 week, 1 month, and 3 months after RFA. After completion of RFA, patients are followed by clinical examination and conventional scanning at 6, 9, and 12 months. PROJECTED ACCRUAL: A total of 80 patients will be accrued for this study.

18F-FDG PET/CT: I.V. injection of 5 to 15 mCi (185 to 555 MBq) of 18F-FDG. Capture time of 60 to 90 minutes. Acquisition of images: A whole body CT scan with normal breathing will be performed for attenuation correction with 5mm thick slices. A whole body PET acquisition of 6 or 7 steps will be done from the upper third of the thighs to the base of the skull. PETC/CT performed at inclusion, 1 month et 3 months after RFA. RFA: Treatment procedure: the location under scanner allows to place the electrode in the center of the tumor. The treatment then lasts 15 to 20 minutes. CT scanner: The CT examination will be performed in spiral acquisition without or after injection of contrast medium (70 ml at 2 or 3 ml/sec). On a 16-slice scanner, the examination is performed with 1.25 mm slices every 0.9. Constants generally used 120kV, 350 mA. Ct scanner performed at inclusion, 48H post-RFA, 1 month, 3 months, 6, 9 and 12 months after RFA.

Accuracy of PET/CT scan to determine response of patients at 3 months will be assessed and compared with standard biopsy 3 months after RFA ,if performed or follow-up at 12 months. Number of patients with true positive results plus number of patients with true negative results divided by the number of evaluable patients (accuracy).

Sensitivity of PET/CT scan to determine response of patients at 3 months will be assessed and compared with standard biopsy 3 months after RFA ,if performed or follow-up at 12 months. Number of patients with true positive results divided by the number of patients with true positive plus false negative results (sensitivity)

Specificity of PET/CT scan to determine response of patients at 3 months will be assessed and compared with standard biopsy 3 months after RFA ,if performed or follow-up at 12 months. Number of patients with true negative results divided by the number of patients with true negative plus false positive results (specificity)

DISEASE CHARACTERISTICS: Histologically confirmed cancer Radiologically suspected pulmonary metastases May be confirmed histologically or by specific markers Less than 6 lesions Lesions < 40 mm Prior positron emission tomography shows 1 hyperfixation (standard uptake variable > 3) at the level of lesions to be treated Lesions must not be attached to or next to major mediastinal structures Radiofrequency ablation planned as treatment PATIENT CHARACTERISTICS: Life expectancy > 6 months No uncontrolled medical condition, including any of the following: Psychiatric condition Infection Coronary insufficiency New York Heart Association class III-IV heart disease No other serious condition No contraindication to general anesthesia Not pregnant or nursing PRIOR CONCURRENT THERAPY: At least 30 days since prior participation in an investigational study At least 30 days since prior chemotherapy No other concurrent investigational agents

Bonichon F, Palussiere J, Godbert Y, Pulido M, Descat E, Devillers A, Meunier C, Leboulleux S, de Baere T, Galy-Lacour C, Lagoarde-Segot L, Cazeau AL. Diagnostic accuracy of 18F-FDG PET/CT for assessing response to radiofrequency ablation treatment in lung metastases: a multicentre prospective study. Eur J Nucl Med Mol Imaging. 2013 Dec;40(12):1817-27. doi: 10.1007/s00259-013-2521-9. Epub 2013 Sep 17.