Physicians Embrace PET Scans for Follicular Lymphoma

Colin Gittens

February 2011, Vol 2, No 1 - Meeting Highlights

Orlando, FL—De spite little evidence supporting its use, fluorodeoxyglucose positron-emission tomography (FDG-PET) is often used to initially stage follicular lymphoma (FL), and this may lead to greater use of early therapy for the disease.

FL is the most common lymphoma, and between 25% and 33% of patients will be diagnosed with early-stage disease, according to lead author Karim E. Abou-Nassar, MD, of the Division of Hematologic Malignancies, Dana- Farber Cancer Institute in Boston. FDG-PET offers improved diagnostic accuracy in several lymphomas, and in FL its use can upstage 18% to 45% of patients and lead to changes in their management.

The researchers’ analysis of the Nation al Comprehensive Cancer Network (NCCN)’s Non-Hodgkin’s Lympho ma Outcomes Database included 953 eligible patients (those newly diagnosed with low-grade FL) from among 7 participating NCCN centers. The patients received staging imaging within 6 weeks of diagnosis; 532 underwent FDG-PET as part of initial staging.

Of the 189 patients with early-stage follicular lymphoma (ESFL), 120 underwent FDG-PET for initial staging. Use of FDG-PET varied significantly across NCCN centers, ranging from 25% to 78%. Choice of initial treatment strategy for ESFL, however, did not vary significantly by use of FDG-PET.

Initial treatment strategy for ESFL also varied significantly according to NCCN centers (P <.001). For all patients diagnosed with ESFL, 55 were treated with radiotherapy alone, 68 with chemother apy/immunotherapy (CIT) alone, 28 with combined radiotherapy and CIT, and 38 were simply observed.

Patients undergoing FDG-PET scans were much more likely to be treated within 6 months of diagnosis, and were more likely to receive an anthracycline- based treatment regimen. A treatment trend that did not reach statistical significance was greater use of chemo therapy and less use of radiotherapy among those receiving an FDG-PET scan.

The study was limited by being set in academic centers only, and by the authors not having the imaging results that would allow them to determine the upstaging rate, said Dr Abou- Nassar.

Nevertheless, when asked if the study indicates that America’s best cancer hospitals are overtreating patients with FL, Dr Abou-Nassar agreed that patients are receiving early therapy, and “there is no evidence that early therapy improves long-term outcomes.” The study was not set up to track patient outcomes, he said.