PETIncluded in Guidelines for Eval of EarlyStage Lung Cancer

[RandyW]

Positron Emission Tomography Included in Guidelines for Evaluation of Early-Stage Lung Cancer Patients: Presented at NCCN

By Ed Susman

HOLLYWOOD, Fla -- March 10, 2008 -- New guidelines from the National Comprehensive Cancer Network give emphasis to the use of fluorodeoxyglucose (FDG)-positron emission tomography (PET) scanning for the evaluation of patients diagnosed with early-stage non-small-cell lung cancer (NSCLC).

"We have other scanning methods -- computer-assisted tomography, magnetic resonance imaging, mediastinoscopy, ultrasound -- but at the end of the day, PET is helpful because it can pick up occult metastases," said David S. Ettinger, MD, Alex Grass Professor of Oncology, as well as Professor of Medicine, Otolaryngology, Head and Neck Surgery, Obstetrics & Gynaecology, and Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland.

"[PET] also has prognostic abilities, but it also has deficiencies. It doesn't make histological diagnoses. Inflammation is positive, brown fat is positive -- and of course, cancer is positive as well," Dr. Ettinger said on March 6 at the National Comprehensive Cancer Network (NCCN) 13th Annual Conference: Clinical Practice Guidelines and Quality Cancer Care.

On the plus side, however, when compared with CT scans, PET is more sensitive (91% to 75%) and more specific (86% to 66%), according to previous research (Pieterman RM et al. N Engl J Med. 2000;343:254-261), Dr. Ettinger said in his review of the rationale for including PET as part of the pretreatment evaluation for stage I and II NSCLC.

"PET may be used to direct lymph node biopsies of the mediastinum but mediastinoscopy remains the gold standard for staging the mediastinum," he said. "PET is valuable for assessment of distant metastases. However, if the PET findings are going to change staging, you need histologic confirmation."

Dr. Ettinger explained that FDG-PET identifies areas of hypermetabolic sites such as neoplasia or inflammation. "In about 10% to 20% of cases, PET reveals occult metastases, thereby precluding futile, expensive thoracotomies," he said.

He noted that PET scans may provide prognostic value as well. About 80% of patients that are determined to have a complete response to definitive treatment according to a PET scan have a 2-year overall survival compared with a 2-year survival rate of 40% if the PET finding is a partial response and 15% if the PET scan reveals no response.

[Presentation title: Update: Non-Small Cell Lung Cancer Guidelines.]