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

Abstract

Diffuse large B‐cell lymphoma (DLBCL) is the most frequent subtype of non‐Hodgkin lymphoma. High total metabolic tumor volume (TMTV) calculated using 18F‐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 18F‐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 cm3 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 cm3 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 cm3 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 18F‐FDG PET/CT that can predict treatment outcomes of patients with DLBCL.

Prognostic impact of six versus eight cycles of standard regimen in patients with diffuse large B-cell lymphoma: propensity score-matching analysis

“…We carried out sensitivity analyses to minimize or avoid immortal time bias and to address the concern of per protocol set analysis by the time-dependent Cox regression analysis and the interim analysis with sIL-2R, respectively. 10,11 These sensitivity analyses, while important and supportive, cannot definitively address potential bias arising from the immortal bias and per protocol set analysis. However, when considering the effect of residual bias on the results, the primary finding from our study that prognosis was no better with eight cycles of (R-) CHOP or THP-COP-21 than with six cycles was consistent across the sensitivity analysis.…”

“…Histologic diagnoses were made according to the Revised European American Lymphoma classification and the World Health Organization classification. 8 , 9 Patient age, sex, anthropometric data (height and weight), performance status (PS), number of extranodal sites, stage, elevated lactate dehydrogenase, serum albumin (Alb), serum soluble interleukin-2 receptor (sIL-2R), 10 , 11 International Prognostic Index (IPI), B symptoms (fevers, night sweats, or unintentional weight loss), and bulky mass (diameter >7.5 cm) were collected as baseline demographic data. 12 , 13 Comorbidity and nutrition status at diagnosis were assessed by the Charlson Comorbidity Index (CCI) and Geriatric Nutritional Risk Index (GNRI).…”

High metabolic heterogeneity on baseline 18FDG-PET/CT scan as a poor prognostic factor for newly diagnosed diffuse large B-cell lymphoma

“…We retrospectively analyzed the prognostic values of MH on baseline 18 FDG-PET/CT in 2 independent cohorts; this was the same population that we used in a previous study to explore the prognostic values of TMTV and sIL-2R. 4 In brief, the training cohort consisted of 86 newly diagnosed DLBCL patients treated at Sapporo Hokuyu Hospital between 2008 and 2013. The validation cohort included 64 patients treated at Aiiku Hospital between 2008 and 2014.…”

“…We previously reported that baseline total metabolic tumor volume (TMTV) on baseline 18 FDG-PET/CT was positively correlated with the serum level of soluble interleukin-2 receptor (sIL-2R), and TMTV and sIL-2R were useful prognostic biomarkers in newly diagnosed DLBCL. 4 High metabolic heterogeneity (MH) on 18 FDG-PET/CT is the index of heterogeneity of intratumoral 18 F-fluorodeoxyglucose uptake distribution, and it is associated with worse prognosis for various tumors. 5 Recently, high MH on the baseline 18 FDG-PET/CT image has been shown to predict worse prognosis of primary mediastinal B-cell lymphoma.…”

Quantitative FDG PET Assessment for Oncology Therapy

“…A recent study has reported evidence of the ability of volumetric indices to predict prognosis [ 36 ]. Although the volumetric indices are very useful, they are rarely mentioned in daily radiology reports because there is no consensus on how to determine the tumour boundary.…”