Correlation between immunophenotypes and metabolic activity measured by¹⁸F-FDG PET/CT in newly diagnosed patients with T cell lymphomas

Introduction: Acknowledgments This study was supported by grants from the National Special Fund for the Development of Major Research Equipment and Instruments (2011YQ03011409), Twelfth “Five-Year" Plan for Science & Technology Support (2014BAA03B03).

Purpose: To analyze the metabolic activity of ¹⁸F-FDG in patients with T cell lymphomas and to explore the relationship between the degree of FDG accumulation and immunophenotypes.

Methods: Patients with newly diagnosed T cell lymphomas from Jul 2010 to Dec 2017 in Peking University First Hospital underwent positron emission tomography/computed tomography (PET/CT) examination were retrospectively reviewed. Sixty four patients (32 Male and 32 Female with the average age of 46.5) were enrolled in the study according to the inclusion and exclusion criteria. All the patients received ¹⁸F-FDG PET/CT examination before treatment, which confirmed by pathology with detailed immunohistochemical results. Maximum standard uptake value (SUVmax) at the biopsy site was measured to explore its correlation with immune phenotypes. The relationship between SUVmax and immune indicators was tested by Spearman. P<0.05 was considered statistically significant.

Results: SUVmax at biopsy site in 64 of patients ranged from 2.2 to 24.4, with the median 8.0. The statistical analysis showed that SUVmax at biopsy site was positively related with Ki-67 and CD5 (r = 0.307, P= 0.024 and r = 0.814, P= 0.002), but found no correlation with other immunological indicators (P>0.05).

Conclusions: SUVmax at biopsy site was positively correlated with Ki-67 and CD5, suggesting that tumour metabolic activity seems to be related to the proliferation and aggressiveness. Keywords T lymphomas, PET/CT, Maximum standardized uptake value, Immunophenotypes