MR imaging, apparent diffusion coefficient and histopathological features of desmoplastic infantile tumors-own experience and review of the literature.

PURPOSE: Desmoplastic infantile tumors are rare supratentorial brain lesions occurring in children under 18 months of age. We report characteristic neuroimaging with DWI and the histopathological features of these neoplasms.
METHODS: Magnetic resonance (MR) examinations of nine patients, aged 0-18 months (median age 3.5 months), were retrospectively analyzed. Analysis of MR images included location and tumor size, signal intensity, contrast enhancement, presence of edema, and hemorrhage. Minimum and mean value of apparent diffusion coefficient (ADC) in the solid component of the tumor and contralateral normal-appearing white matter (NAWM) were measured, and ADC/NAWM ratios were calculated. All patients underwent tumor resection, and diagnosis of grade I desmoplastic tumors was confirmed.
RESULTS: The tumors were located in the temporal lobe in seven patients, the parietal lobe in three, and in the frontal lobe in one case (in two children, tumors invaded more than one lobe). Suprasellar localization was observed in two patients; one child had multifocal brain lesions. In five cases, signal intensity of the solid component was hypointense on T2-WI. The measured minimum ADC value of solid tumor varied from 0.606 to 1.020 × 10(-3) mm(2)/s, with a mean value of 0.921 × 10(-3) mm(2)/s. The mean ADC value of NAWM was 1.121 × 10(-3) mm(2)/s. The mean ADC ratio was 0.858 × 10(-3) mm(2)/s.
CONCLUSION: From our series, we can assume that restricted diffusion is observed not only in malignant but also in benign brain tumors. Diffusion signals and ADC values in these neoplasms appear to depend on their cellularity and components of the extracellular matrix.