No abstract

Introduction: Body composition (BC) influences chemotherapy toxicity, surgical complication rates, and overall survival in cancer patients. While recent studies have shown the connection between BC and clinical outcomes in adult oncology populations, BC measures are still often overlooked in the pediatric, adolescent, and young adult (AYA) oncology populations. The objective of this study was to determine the effect of BC on the occurrence of venous thromboembolism (VTE) in pediatric and AYA patients with lymphoma. Methods: Skeletal muscle (SkM), subcutaneous adipose tissue (SAT), and visceral adipose tissue (VAT) volumes were manually segmented at vertebral level L3 from 5 consecutive axial CT images ( Fig. 1A ) acquired in a 5-year retrospective cohort of 78 patients with lymphoma (mean age = 13.3 ± 0.6 years). All CT images were acquired at initial staging of disease. Incidence of VTE, including deep vein thrombosis and pulmonary embolism, was evaluated for 12 months after diagnosis. Results and Conclusions: In the first 12 months after diagnosis, 26 of 88 patients (33%) had a VTE event. Patients with VTE had a significantly higher percent of SAT (p = 0.022) and lower percent of SkM (p = 0.036) compared to patients without VTE ( Fig. 1B ). Patients were stratified based on a SkM/SAT cut-off ratio of 0.963, determined using the Receiver-Operating-Characteristic Curve. Patients who were below this SkM/SAT cutoff ratio had a significantly higher probability for VTE in the first 12 months compared to patients who were above the cutoff (log-rank test, p < 0.005) ( Fig. 1C ). This cutoff ratio remained significant after correcting for lymphoma subtype, body mass index, age, and sex using the Cox Proportional-Hazards model. Standard-of-care CT imaging may offer a technique for evaluating BC and predicting outcomes such as VTE in pediatric and AYA patients, thereby offering personalized approaches to cancer care by guiding chemotherapy dosing and nutritional recommendations.

Introduction: Lymphoma treatment with chemotherapy, alone or in combination with radiation therapy, can have off-target effects that lead to vascular toxicity, which has recently gained attention in the field of cardio-oncology. Positron emission tomography (PET)/computed tomography (CT) imaging with fluorine-18 ( 18 F)-fluorodeoxyglucose (FDG) is standard of care for monitoring lymphoma treatment responses and is a widely accepted tool for assessing vascular inflammation. We hypothesized that 18 F-FDG PET/CT imaging could detect and quantify chemotherapy-induced increases in vascular inflammation following the first cycle of lymphoma treatment in pediatric, adolescent, and young adult (AYA) patients. Methods: Whole-body 18 F-FDG PET/CT images were retrospectively acquired at initial staging of disease and first treatment follow-up for pediatric and AYA lymphoma patients (n=33). Regions of interest were manually drawn using each axial slice of fused PET/CT images for the femoral and popliteal arteries/veins to quantify serial changes in vascular uptake of 18 F-FDG. The changes in the average maximum standard uptake value (SUV max ) for the femoral-popliteal vessels were calculated. Results and Conclusions: The patient population consisted of Non-Hodgkin (55%) and Hodgkin (45%) lymphoma patients with a mean age of 13 years (SD=4.7). 18 F-FDG PET/CT imaging detected ( Fig. 1A ) and quantified a significant increase in the mean SUV max from baseline (0.94±0.03) to first treatment follow-up (1.06±0.02) for the femoral and popliteal arteries/veins ( Fig. 1B ). Standard of care 18 F-FDG PET/CT imaging can non-invasively quantify chemotherapy-induced vascular inflammation in young cancer patients in response to the first cycle of treatment, thus representing an approach for evaluating vascular toxicity and creating novel opportunities for personalized medicine focused on reducing cardiovascular side effects of chemotherapy.

Background: Positron emission tomography (PET)/computed tomography (CT) imaging can detect changes in arterial inflammation, but has not been used to evaluate chemotherapy-induced venous inflammation or assess risk for venous thromboembolism (VTE) in pediatric oncology. Therefore, the purpose of this study was to evaluate the prognostic value of fluorine-18-fluorodeoxyglucose PET/CT imaging of venous inflammation for predicting VTE occurrence in the 12 months after lymphoma diagnosis in pediatric, adolescent, and young adult patients. Methods: Pediatric, adolescent, and young adult patients with lymphoma diagnoses (n=71) who underwent whole-body PET/CT imaging at initial staging of disease and first therapeutic follow-up were retrospectively evaluated for serial changes in lower extremity venous uptake of fluorine-18-fluorodeoxyglucose. PET/CT images were used to segment and quantify serial changes in fluorine-18-fluorodeoxyglucose uptake for veins of interest (ie, popliteal and femoral). Incidence of VTE was assessed for 12 months after lymphoma diagnosis. Results: PET/CT detected a significantly higher inflammatory response in the femoral ( P =0.012) and popliteal ( P =0.013) veins of patients who experienced a VTE event compared with those who remained VTE free in the 12 months after diagnosis. The area under the curve values for receiver operator characteristics analyses were 0.76 (femoral vein) and 0.77 (popliteal vein) based on incidence of VTE occurrence. Univariate analyses demonstrated that PET/CT-derived changes in femoral ( P =0.008) and popliteal ( P =0.002) vein inflammation were significantly associated with VTE-free survival at 12 months after diagnosis. Conclusions: Fluorine-18-fluorodeoxyglucose PET/CT imaging detects treatment-induced venous toxicity that may provide insight into risk of VTE events in pediatric and adolescent and young adult patients with lymphoma.