Soft-tissue masses: when and how to biopsy

Patients with soft-tissue tumors present a diagnostic challenge to the clinician. A systematic approach to evaluation and biopsy is necessary to minimize diagnostic errors and biopsy complications. With MRI, the clinician and radiologist are able to precisely identify some soft-tissue masses, such as lipomas, ganglions, hemangiomas, and popliteal cysts. Most soft-tissue tumors have signal characteristics that are low signal on T1-weighted images and high signal on T2-weighted images. Soft-tissue masses that cannot be identified are called indeterminate masses, and a biopsy is necessary to identify these lesions. Needle biopsy and open incisional biopsy are effective methods to histologically identify the nature of the tumor. Open excisional biopsy should be performed only when the surgeon knows that the soft-tissue lesion is benign.