Soft-Tissue Tumors About the Knee.

Soft-tissue tumors about the knee include a wide variety of entities, ranging from synovial cysts to aggressive high-grade sarcomas. The overlap in clinical presentation of these various masses frequently results in misdiagnosis and inappropriate treatment. Unnecessary and sometimes costly arthroscopy sometimes precedes the diagnosis of soft-tissue sarcoma about the knee. A poorly planned or executed biopsy has been demonstrated to have an adverse effect on patient prognosis and may lead to unnecessary amputation. Special vigilance in evaluation is warranted when a soft-tissue mass is not in the typical position or does not have other characteristic features of a meniscal or Baker's cyst, when the size of the mass or the accompanying symptoms seem out of proportion to the injury or underlying degenerative process, and when symptoms persist beyond what is expected. When malignancy is suspected, the patient should be referred to a musculoskeletal oncologist before biopsy.