- A retrospective analysis concludes that the 2-[18F]-fluoro-2-deoxy-d-glucose positron emission tomography (FDG-PET) quantitative parameters of homogeneity and sphericity are associated with PFS of patients with pharynx squamous cell carcinoma (SCC).
Why this matters
- This study lends support to the use of a tumor’s 3D shape on FDG-PET for predicting treatment outcomes.
- Higher homogeneity and sphericity were associated with improved PFS (HR, 1.76 [P=.02] and 2.71 [P=.01], respectively) in multivariate analysis.
- This result was confirmed in Kaplan-Meier analysis (P=.01 for homogeneity and P=.002 for sphericity).
- A cutoff value of 0.37 for homogeneity was associated with sensitivity of 91%, specificity of 58%, positive predictive value (PPV) of 80%, negative predictive value (NPV) of 78%, and accuracy of 79% for PFS.
- A cutoff value of 0.35 for sphericity was associated with sensitivity of 74%, specificity of 94%, PPV of 96%, NPV of 67%, and accuracy of 81% for PFS.
- Patients with high homogeneity (≥0.37) and high sphericity (≥0.35) had longer PFS than patients with either high homogeneity or high sphericity, who had longer PFS than patients with both low homogeneity (
- No analyzed parameter was significantly associated with OS.
- 54 patients with pharynx SCC were analyzed for 14 FDG-PET parameters to identify associations with survival outcomes.
- Funding: None disclosed.
- Small patient sample size.
- Retrospective study.