24 year-old female with cystic mass over fifth metatarsal There is a lobulated lesion dorsal to the proximal fifth metatarsal measuring1.4 x 1.6 x 1.6 cm with heterogeneously increased T2 signal, intermediate T1 signal and heterogeneous enhancement. The lesion surrounds and appears inseparable from the extensor tendon sheath. The underlying bone marrow signal and cortex is within normal limits. There is mild edema and enhancement of the surrounding soft tissues.
Heterogeneously enhancing lesion dorsal to fifth metatarsal as described above for which an underlying infectious or neoplastic process should be considered. This would be atypical for a simple ganglion cyst, although a complicated cyst with hemorrhage or infection remains on the differential. Ultrasound guided biopsy may be considered for further evaluation.