Variations in apparent diffusion coefficient values following chemotherapy in pediatric neuroblastoma

Area of Science:

• Pediatric Oncology
• Radiology
• Biomarkers

Background:

• Chemotherapy response in pediatric solid tumors is often assessed by size reduction, which is unreliable and a late indicator due to necrosis.
• Novel imaging biomarkers are needed for early and accurate assessment of treatment efficacy.

Purpose of the Study:

• To determine if apparent diffusion coefficient (ADC) values in childhood neuroblastomas change proportionally with chemotherapy response.
• To evaluate diffusion-weighted MRI as a noninvasive biomarker for therapeutic response.

Main Methods:

• Retrospective analysis of MRI scans from 15 pediatric patients with abdominopelvic neuroblastomas before and after chemotherapy.
• Region-of-interest analysis of solid/contrast-enhancing tumor portions to determine ADC values.
• Comparison of pre- and post-chemotherapy ADC values.

Main Results:

• A statistically significant increase in post-chemotherapy ADC values (minimum, maximum, and median) compared to pre-treatment values (P < 0.05).
• Demonstrated a clear trend of increasing ADC values with chemotherapy treatment.

Conclusions:

• Diffusion-weighted MRI, assessed by ADC values, shows promise as a noninvasive biomarker for evaluating chemotherapy response in pediatric neuroblastomas.
• This study is the first to report on diffusion-weighted imaging findings before and after chemotherapy in childhood neuroblastic tumors.