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.

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