Presentation
Painless mass of the left thigh
Patient Data
There is a well-defined hypoechoic heterogeneous ovoid mass of intermuscular location within the posterior compartment of the left distal thigh.
The MRI sequences demonstrate a well-circumscribed ovoid mass (5.5x4.5x4 cm) in the posterior compartment of the lower 1/3 of the left thigh of intermuscular location between the biceps femoris laterally, semimembranosus/semitendinosus medially, and popliteal vessels anteriorly, inseparable from the sciatic nerve. It displays an intermediate signal with areas of high signal on T1WI, inhomogeneous high signal on T2WI/STIR with an intense and heterogeneous enhancement on postcontrast sequences.
Case Discussion
MRI features of well circumscribed ovoid mass in the posterior compartment of the lower thigh inseparable from the sciatic nerve most consistent of a peripheral nerve sheath tumor (PNST).