Serum level of soluble interleukin‐2 receptor is positively correlated with metabolic tumor volume on 18 F‐FDG PET/CT in newly diagnosed patients with diffuse large B‐cell lymphoma

摘要

Diffuse large B‐cell lymphoma (DLBCL) is the most frequent subtype of non‐Hodgkin lymphoma. High total metabolic tumor volume (TMTV) calculated using 18 F‐FDG PET/CT images at diagnosis predicts poor prognosis of patients with DLBCL. However, high cost and poor access to the imaging facilities hamper wider use of 18 F‐FDG PET/CT. In order to explore a surrogate marker for TMTV, we evaluated the correlation between the serum levels of soluble interleukin‐2 receptor (sIL‐2R) and TMTV in 64 patients with DLBCL, and the results were verified in an independent validation cohort of 86 patients. Serum levels of sIL‐2R were significantly correlated with TMTV. ROC analysis revealed that the cutoff value of TMTV ≥150?cm 3 or sIL‐2R ≥?1300?U/mL could predict failure to achieve EFS24 with areas under the curve (AUC) 0.706 and 0.758, respectively. Each of TMTV ≥150?cm 3 and sIL‐2R ≥1300?U/mL was significantly associated with worse 5‐year overall survival and event‐free survival. Importantly, each of sIL‐2R 1300?U/mL or TMTV 150?cm 3 identified patients with favorable prognosis among NCCN‐IPI high‐intermediate and high‐risk group. Serum level of sIL‐2R represents a convenient surrogate marker to estimate metabolic tumor burden measured by 18 F‐FDG PET/CT that can predict treatment outcomes of patients with DLBCL.