Ancient Schwannoma as an exceptional thoracic spinal tumor: A case report.

Schwannomas are mostly benign tumors arising from the nerve sheath. These tumors can be found anywhere in the body. Depending on their locations, they may cause compressive symptoms as well as cosmetic or functional defects. Ancient schwannomas, the rare variant of schwannomas, are the slow-growing tumors characterized with cystic necrotic degeneration areas in the neoplastic tissue. Ancient schwannomas rarely occur in the spinal canal, they are particularly unusual in the thoracic spine. Herein we present a 66-year-old woman with chronic back pain who is detected a cystic mass in her thoracic spine by magnetic resonance imaging and is diagnosed with ancient schwannoma by histological examination.

The ability and utility of diffusion-weighted magnetic resonance imaging with different 'b' values in the differentiation of benign from malignant lung lesions.

PURPOSE: To evaluate the ability and the utility of diffusion-weighted magnetic resonance imaging (MRI) with different 'b' values to visualise benign and malignant lung lesions, and to determine which 'b' value (b = 300, 500, or 1000 s/mm2) was most useful in differentiating benign from malignant lung lesions. MATERIAL AND METHODS: A total of 100 patients (28 women, 72 men; mean age = 57.19 ± 13.44 years; age range = 20-83 years). Diffusion-weighted imaging (DWI) was obtained with 'b' values of 300, 500, and 1000 s/mm2. The signal intensity of lesions on DWI images was analysed, and the apparent diffusion coefficient (ADC) values of the lesions were calculated. MRI was performed in all patients after having presented at our department for thoracic computed tomography for various reasons. RESULTS: A statistically significant difference in DWI signal scores was detected between benign and malignant lesions for all 'b' factors (p < 0.0001 for each). The sensitivity and specificity were 95% and 64%, respectively, when a score of 3 for ß = 300 s/mm2; 90% and 69%, respectively, when a score of 3 for ß = 500 s/mm2; and 84% and 74%, respectively, when a score of 3 for ß = 1000 s/mm2. ADC values showed significant differences between benign and malignant lesions for all 'b' factors (p < 0.0001 for each). CONCLUSIONS: Using 'b' values of 300, 500, and 1000 s/mm2, DWI signal intensity scores and ADC values are effective methods for the differential diagnosis of malignant and benign pulmonary lesions.

Usefulness of Apparent Diffusion Coefficient of Diffusion-Weighted Imaging for Differential Diagnosis of Primary Solid and Cystic Renal Masses.

BACKGROUND: To evaluate the value of diffusion-weighted imaging (DWI) for distinguishing between benign and malignant renal masses. MATERIAL/METHODS: Seventy-five patients with 75 unilateral renal lesions were included, and 75 normal contralateral kidneys served as controls. The lesions were categorized into four groups as malignant cystic, malignant solid, benign cystic and benign solid. The apparent diffusion coefficients (ADCs) were evaluated for two different b values (b=600 s/mm2 and b=1000 s/mm2). Receiving operating characteristic analysis was performed to identify threshold ADCs. RESULTS: Sensitivity and specificity were 67% and 77% (p=0.003) at the cutoff value of 1.5 for b=600 s/mm2, and 79% and 62% (p=0.004) at the cutoff value of 1.99 for b=1000 s/mm2 as regards the differentiation between solid benign and malignant renal lesions. Sensitivity and specificity were 78% and 79% (p=0.001) at the cutoff value of 3.1 for b=600 s/mm2, and 86% and 61% (p=0.003) at the cutoff value of 2.9 for b=1000 s/mm2 as regrads the differentiation between benign and malignant cystic renal lesions. CONCLUSIONS: DWI can be an effective diagnostic method for distinguishing between benign and malignant renal masses.