Correlation between apparent diffusion coefficient (ADC) and cellularity is different in several tumors: a...

Area of Science:

• Radiology and Oncology
• Medical Imaging
• Cancer Research

Background:

• Apparent diffusion coefficient (ADC) is a quantitative MRI biomarker.
• Tumor cellularity, a measure of cell density, is a key histopathological feature.
• Understanding the relationship between ADC and cellularity can aid in non-invasive tumor assessment.

Purpose of the Study:

• To synthesize existing clinical evidence on the association between ADC and tumor cellularity.
• To provide a pooled correlation estimate based on a large patient cohort.
• To explore this relationship across diverse tumor types.

Main Methods:

• Systematic literature search of Medline for studies published up to September 2016.
• Inclusion of English-language publications reporting ADC and cellularity data.
• Meta-analysis of 39 studies involving 1530 patients, following PRISMA guidelines.

Main Results:

• A pooled correlation coefficient of ρ = -0.56 (95% CI [-0.62; -0.50]) indicates a moderate inverse relationship between ADC and cellularity.
• Correlation varied by tumor type, with stronger inverse relationships observed in glioma (ρ = -0.66) and ovarian cancer (ρ = -0.64).
• Other tumor types like lung cancer, cervical cancer, and prostate cancer also showed significant inverse correlations.

Conclusions:

• A consistent inverse correlation exists between ADC and tumor cellularity across multiple cancer types.
• ADC shows potential as a non-invasive imaging biomarker for estimating tumor cellularity.
• Further research may refine the utility of ADC in characterizing tumor biology and guiding treatment decisions.