Differentiation between malignant and benign musculoskeletal tumors using diffusion kurtosis imaging

• Published in: Skeletal radiology Vol. 48; no. 2; pp. 285 - 292
• Main Authors: Ogawa, Masaki, Kan, Hirohito, Arai, Nobuyuki, Murai, Taro, Manabe, Yoshihiko, Sawada, Yusuke, Shibamoto, Yuta
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.02.2019; Springer; Springer Nature B.V
• Subjects: Adult; Aged; Benign; Biocompatibility; Biomedical materials; Bone Neoplasms - diagnostic imaging; Cancer; Diagnosis; Diagnosis, Differential; Diagnostic systems; Diffusion; Diffusion coefficient; Diffusion Magnetic Resonance Imaging - methods; Female; Humans; Image Enhancement; Image Interpretation, Computer-Assisted; Imaging; Kurtosis; Male; Mathematical analysis; Medical imaging; Medical research; Medicine; Medicine & Public Health; Medicine, Experimental; Middle Aged; Muscular system; Neck; Nuclear Medicine; Orthopedics; Osteolysis; Pathology; Pelvis; Prospective Studies; Radiology; Retroperitoneum; Soft Tissue Neoplasms - diagnostic imaging; Tumors; MR imaging; Differentiation; Diffusion weighted imaging; Musculoskeletal tumor; Diffusion kurtosis imaging
• ISSN: 0364-2348; 1432-2161
• DOI: 10.1007/s00256-018-2946-0

Objective The purpose of this study was to evaluate differences in parameters of diffusion kurtosis imaging (DKI) and minimum apparent diffusion coefficient (ADC min ) between benign and malignant musculoskeletal tumors. Materials and methods In this prospective study, 43 patients were scanned using a DKI protocol on a 3-T MR scanner. Eligibility criteria were: non-fatty, non-cystic soft tissue or osteolytic tumors; > 2 cm; location in the retroperitoneum, pelvis, leg, or neck; and no prior treatment. They were clinically or histologically diagnosed as benign ( n  = 27) or malignant ( n  = 16). In the DKI protocol, diffusion-weighted imaging was performed using four b values (0-2000 s/mm 2 ) and 21 diffusion directions. Mean kurtosis (MK) values were calculated on the MR console. A recently developed software application enabling reliable calculation was used for DKI analysis. Results MK showed a strong correction with ADC min (Spearman’s rs = 0.95). Both MK and ADC min values differed between benign and malignant tumors ( p  < 0.01). For benign and malignant tumors, the mean MK values (± SD) were 0.49 ± 0.17 and 1.14 ± 0.30, respectively, and ADC min values were 1.54 ± 0.47 and 0.49 ± 0.17 × 10 −3  mm 2 /s, respectively. At cutoffs of MK = 0.81 and ADC min  = 0.77 × 10 −3  mm 2 /s, the specificity and sensitivity for diagnosis of malignant tumors were 96.3 and 93.8% for MK and 96.3 and 93.8% for ADC min , respectively. The areas under the curve were 0.97 and 0.99 for MK and ADC min , respectively ( p  = 0.31). Conclusions MK and ADC min showed high diagnostic accuracy and strong correlation, reflecting the accuracy of MK. However, no clear added value of DKI could be demonstrated in differentiating musculoskeletal tumors.