Higher Baseline Metabolic Tumor Volume May Predict Poorer Outcome in Patients With High Tumor Burden Follicular Lymphoma


Key Points

  • Higher baseline total metabolic tumor volume was associated with poorer progression-free and overall survival in patients with high tumor burden follicular lymphoma.
  • Use of total metabolic tumor volume and FLIPI2 score together distinguished three risk groups for progression-free survival.

In a pooled analysis reported in the Journal of Clinical Oncology, Meignan et al found that higher baseline total metabolic tumor volume measured by 18F-fluorodeoxyglucose (18F-FDG) positron-emission tomography–computed tomography (FDG PET-CT) was associated with poorer outcome in patients with high tumor burden follicular lymphoma.

Study Details

The analysis included 185 patients receiving immunochemotherapy in 3 multicenter trials. Total metabolic tumor volume was computed using the 41% maximum standardized uptake value threshold method. Patients had a median age of 55 years, 92% had stage III to IV disease, 37% had a Follicular Lymphoma International Prognostic Index (FLIPI) score of 3 to 5, and 31% had a FLIPI2 score of 3 to 5.

Total Metabolic Tumor Volume and Outcome

Median follow-up was 64 months. Among all patients, 5-year progression-free survival was 55%, and overall survival was 92%. The median total metabolic tumor volume was 297 cm3. Optimal cutoff was identified as 510 cm3, with survival being poorer in the 29% of patients with total metabolic tumor volume > 510 cm3. For higher vs lower total metabolic tumor volume, 5-year progression-free survival was 33% vs 65% (hazard ratio [HR] = 2.90, P < .001), and 5-year overall survival was 85% vs 95% (HR = 3.45, P = .010).

Total Metabolic Tumor Volume and FLIPI2

On multivariate analysis, total metabolic tumor volume (HR = 2.3, P = .002) and FLIPI2 score (HR = 2.2, P = .002) were independent predictors of progression-free survival. Use of these 2 factors together identified risk groups with 5-year progression-free survival of 20% (high total metabolic tumor volume and intermediate-to-high FLIPI2 score; HR = 5.0, P < .001), 46% (high total metabolic tumor volume or intermediate-to-high FLIPI2; HR = 2.1, P = .007), and 69% (low total metabolic tumor volume and low FLIPI2).

The investigators concluded: “Baseline [total metabolic tumor volume] is a strong independent predictor of outcome in [follicular lymphoma]. In combination with FLIPI2 score, it identifies patients at high risk of early progression. It warrants further validation as a biomarker for development of first-line PET-adapted approaches in [follicular lymphoma].”

Michel Meignan, MD, PhD, of the Université Paris-Est Créteil, is the corresponding author of the Journal of Clinical Oncology article.

The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.