Male 58 years old Reason: assess right triceps mass History: present for 10 months Again noted with in the right arm, within the triceps muscle is a 3.8 x 4.6 x 5.0 cm soft tissue mass, stable/mildly increased from prior allowing for differences in imaging technique. Linear high signal and appearance suggestive of a dural tail extends from the superior and inferior aspects of the main body of the mass. This is homogeneously iso-/hypointense to muscle on T1 weighted images and somewhat inhomogeneously hyperintense to muscle on T2 weighted images. Postcontrast it demonstrates rim enhancement and inhomogeneous internal enhancement. It is well delineated without reactive edema in the surrounding musculature. The humerus is unremarkable.
5.0-cm soft tissue mass in the right triceps muscle. Although this may represent a benign peripheral nerve sheath tumor, due to the inhomogeneity, the appearance is somewhat worrisome for a malignant peripheral nerve sheath tumor.