34-year-old male with a left upper extremity soft tissue mass in the biceps. Note is made of a lobulated irregular mass along the lateral aspect of the deltoid and biceps muscles, with associated heterogeneous T1 and T2 prolongation and heterogeneous enhancement on postcontrast sequences, measuring approximately 4.2 x 1.4 x 3.8 cm (TR x AP x CC) as seen on image 23 of series 13 and image 8 of series 14. There is a vitamin E capsule in the overlying area presumably corresponding to the patient's palpable area of concern. There is no definitive evidence to suggest invasion into the surrounding musculature or erosion/destruction of the adjacent bone, although the mass abuts the fascia along the lateral aspect of the deltoid and biceps muscles. Additionally, there are scattered foci of increased bone marrow signal abnormality which become confluent proximally within the anterior humeral head and are associated with enhancement on postcontrast sequences. An intramedullary process such as metastatic disease should be considered in the setting of a primary neoplasm. There is no cortical destruction. The imaged musculature otherwise appears normal.
1. Nonspecific heterogeneous enhancing mass in the subcutaneous soft tissues along the lateral aspect of the deltoid muscle suspicious for a primary malignancy. 2. Enhancing bone marrow signal abnormality in the proximal left humerus. An intramedullary process such as metastatic disease should be considered in the setting of a primary neoplasm.