European Radiology: The value of CT body composition quantification for the evaluation of lymphoma treatment in pediatrics, adolescents and young adults

Multiple studies have shown that body composition (BC) plays an important role in the pharmacokinetics of chemotherapy and plays a role in cancer prognosis in adults Important roles, including chemotherapy tolerability and toxicity, length of hospital stay, infection rates, quality of life, and overall survival
.
However, assessment of BC in clinical settings is largely limited to anthropometric indicators such as skinfold thickness, waist or arm circumference, and body mass index (BMI).

Chemotherapy dosing regimens are also largely based on anthropometric indicators such as body surface area, body weight, and BMI
.
These anthropometric indicators, while readily available and easy to use, vary greatly and cannot distinguish between weight and fat mass
.

Studies of BC using non-anthropometric, non-imaging techniques such as bioelectrical impedance analysis or air displacement plethysmography have consistently shown that cancer patients have significantly reduced
skeletal muscle mass after initiation of treatment, in addition to an increase in fat mass.
However, these techniques can neither distinguish subcutaneous adipose tissue (SAT) from visceral adipose tissue (VAT), nor provide quantitative measurements
of SAT, VAT, and skeletal muscle (SkM).
Dual-energy X-ray bone densitometry (DXA) is an imaging technique that provides quantitative measurements of bone density, muscle and subcutaneous fat content and has been used in large clinical trials
to measure body composition.
However, DXA-derived BC measurements are biased in longitudinal studies of patients, thus limiting their effectiveness in
continuously monitoring BC during the treatment of cancer patients.
At this stage, measurements of SAT, VAT, and SkM can be accurately quantified using computed tomography (CT) or magnetic resonance imaging (MR
).

Although BC plays an important role in adult cancer patients, few studies have explored the role of BC in patients with pediatric, adolescent, and young adult (AYA) tumors, and most studies are limited to acute lymphoblastic leukemia (ALL) but cannot be applied to other haematological malignancies
。 In addition, while early tracking of BC changes is essential for proper planning of diet and exercise recommendations to prevent adverse changes in BC, early changes in BC after initiation of treatment in children and the AYA oncology population remain understudied
.

Recently, a study published in the journal European Radiology compared the differences between BC changes caused by positron emission tomography (PET)/CT scanning, CT and traditional BMI measurement, providing a reference for clinically accurate and early assessment of the condition and treatment of cancer patients
.

In this study, skeletal muscle (SkM), subcutaneous adipose tissue (SAT), and visceral adipose tissue (VAT) volumes were calculated by manual segmentation of low-dose CT images obtained from a 10-year retrospective single-point cohort of 110 lymphoma patients.

CT images and BMI percentiles (BMI%) were obtained from baseline and first treatment follow-up
.
CT image segmentation
at the vertebral L3 level using 5 consecutive axial CT images.

CT imaging detected treatment-induced significant changes in BC measurements from baseline to the first follow-up time point, manifested as significant increases in SAT and VAT and significant decreases
in SkM.
BMI% measurements did not change from baseline to first follow-up and were not significantly correlated
with changes in image-derived BC measurements.
Men under 12 years of age, patients diagnosed with non-Hodgkin lymphoma and developing stage 3 or 4 disease gained more adipose tissue and lost more SkM
in the first treatment cycle compared to their clinical counterparts.

Figure Changes in CT imaging of BC after the first cycle of lymphoma treatment
.
Abdominal CT images of an 18-year-old male patient diagnosed with stage 1 non-Hodgkin lymphoma, and measurements (SAT, VAT, and SkM) for each BC region of interest changed significantly at
treatment follow-up imaging time points when comparing (A) baseline to (B).
At the population level, there was a significant change in each BC measure of interest from baseline to first treatment follow-up, while BMI% remained unchanged
after the first treatment cycle.
N = 110 patients

This study shows that pediatric and AYA lymphoma patients exhibit significant adipose tissue buildup while losing a large amount of SkM
upon their first treatment cycle.
In addition, BC assessed by non-invasive imaging is more sensitive
than BMI in monitoring treatment-induced toxicity.
This study highlights the value of using standard of care images obtained during treatment to quantify and monitor changes in BC and provides new opportunities
to assist in developing treatment plans to optimize lymphoma outcomes in pediatric and AYA patients.

Original source:

Nguyen K Tram,Ting-Heng Chou,Laila N Ettefagh,et al.
Quantification of chemotherapy-induced changes in body composition in pediatric, adolescent, and young adult lymphoma using standard of care CT imaging.
DOI:10.
1007/s00330-022-09048-z