Differentiation between malignant and benign musculoskeletal tumors using diffusion kurtosis imaging

Area of Science:

• Radiology
• Oncology
• Medical Imaging

Background:

• Musculoskeletal tumors require accurate differentiation between benign and malignant types for appropriate patient management.
• Diffusion kurtosis imaging (DKI) and apparent diffusion coefficient (ADC) metrics offer potential for non-invasive tumor characterization.

Purpose of the Study:

• To compare diffusion kurtosis imaging (DKI) parameters, specifically mean kurtosis (MK), and minimum apparent diffusion coefficient (ADCmin) in distinguishing benign from malignant musculoskeletal tumors.

Main Methods:

• A prospective study involving 43 patients with eligible musculoskeletal tumors underwent DKI on a 3-T MR scanner.
• DKI analysis utilized diffusion-weighted imaging with four b values (0-2000 s/mm²) and 21 directions.
• Mean kurtosis (MK) and ADCmin values were calculated and compared between histologically confirmed benign (n=27) and malignant (n=16) tumors.

Main Results:

• Both MK and ADCmin values were significantly different between benign and malignant tumors (p < 0.01).
• Mean MK values were 0.49 ± 0.17 for benign and 1.14 ± 0.30 for malignant tumors.
• Mean ADCmin values were 1.54 ± 0.47 × 10⁻³ mm²/s for benign and 0.49 ± 0.17 × 10⁻³ mm²/s for malignant tumors.
• MK and ADCmin showed high diagnostic accuracy (96.3% specificity, 93.8% sensitivity) for malignant tumors at specific cutoffs.
• MK and ADCmin demonstrated strong correlation (rs = 0.95).

Conclusions:

• MK and ADCmin are highly accurate in differentiating benign and malignant musculoskeletal tumors.
• The strong correlation between MK and ADCmin suggests MK reflects ADCmin accuracy.
• While effective, DKI did not demonstrate a clear added value over ADCmin in differentiating these tumors.