Ruolo della risonanza magnetica nello studio dei feocromocitomi benigni e maligni: analisi quantitativa dell'intensità del segnale di risonanza

In order to assess the clinical role of Magnetic Resonance (MR) imaging in patients with benign or malignant pheochromocytomas, the MR signal intensity ratios of benign and malignant tumors were evaluated. Eighteen patients (9 men and 9 women, mean age: 37 +/- 8 years) with benign (n = 10) or malignant (n = 8) pheochromocytomas were studied. A total of 27 lesions (12 benign and 15 malignant) were analyzed. In all patients, histology confirmed the disease. MR studies were performed using a 1.5-T superconducting magnet system. Sequences were used to obtain T1-weighted (TR/TE 300/12 ms) and T2-weighted (TR/TE 2000/80 ms) images. On both T1- and T2-weighted MR images, the mean absolute signal intensity values of tumor lesions, of liver, muscle and fat tissues, and of image background were measured to obtain the corresponding signal intensity ratios for each lesion. Our results exhibited no statistically significant differences in both T1 and T2 MR signal intensity ratios between benign and malignant lesions. In conclusion, our results suggest that MR imaging cannot differentiate benign from malignant lesions in patients with pheochromocytoma