Alaa  Muslimani,Bor-Tau  Hung,Ching-yee  Oliver Wong,Govinda  Brahmanday,Ishmael  Jaiyesimi,James  Huang,Mohammad Muhsin  Chisti,Paul Rigo,Pek-lan  Khong,
The Correlation between Lymphoma Cell Size and PET-CT Metabolic Activity in Follicular Lymphomas
Radiotherapy and Clinical Oncology
2018
2674-2497
http://dx.doi.org/10.31487/j.RCO.2018.01.006
https://www.sciencerepository.org/the-correlation-between-lymphoma-cell-size-and-PET-CT-metabolic-activity-in-follicular-lymphomas_RCO-1-106 
Abstract: The purpose of this study was to correlate the average lymphoma cell size and metabolic activity in follicular
lymphoma (FL) by comparing to the pathological grading, in a cohort of FL subjects.
Methods: 64 patients with FL were retrospectively studied. 44 cases were grade 1-2 (FL1-2) and 20 were grade
3 (FL3). The average tumor cell size was measured based on flow cytometric analysis of the relative forward
scatters (FSC) of tumor cells relative to that of internal T-cells in the lymphoma tissue. The metabolic activity
was measured using maximal standardized uptake value (SUV) of the involved lymph node by 18F-FDG PET–
CT scan. The SUV was normalized to a glucose level of 100 mg/dl using the formula: SUV100 = SUV x {[100
mg/dl]/[Glc]}g where g = [-0.5] and [Glc] was the glucose level recorded at the time of PET scan. The lymphoma
cell size (FSC) and metabolic activity (SUV100) was cross-tabbed and correlated using cut off values
determined by discriminant analysis.
Results: Average lymphoma cell size of FL3 was significantly (p < 0.0005) greater than that of FL1-2. There
was significant correlation between lymphoma cell size (FSC) and metabolic activity (SUV100) (p = 0.021),
suggesting the possibility of combining these two objective measurements to grade FL.
Conclusions: The significant difference of average lymphoma cell size between FL3 and FL1-2 validate the
utility of flow cytometry in grading FL. The significant correlation between cell size and metabolic activity
suggests that metabolic activity can further serve as an independent criterion in grading.
Keywords: Lymphoma, PET Tumor size SUV