Tumors masquerading as hematomas.

Suboptimal patient management can occur when malignant soft tissue tumors with internal hemorrhage masquerade as simple hematomas. We retrospectively reviewed 31 patients with malignancies who had diagnostic delays averaging 6.7 months (range, 1.0-49.3 months). The diagnoses included soft tissue sarcomas (27), metastatic cancers (three), and lymphoma (one). History of subcutaneous ecchymosis was positive in only five patients (three of whom had trauma), negative in 18, and unknown in eight. Ecchymosis was present in two patients, absent in 20, and unknown in nine. Previous treatments included observation and reassurance (21), aspiration (11), incision and drainage (10), unplanned resections (seven), physical therapy (seven), medication administration (six), and arthroscopy (one). Interpretations of initial MRI (21) and ultrasound (four) did not raise suspicion of underlying cancers. Traumatic hemorrhage usually causes subcutaneous ecchymosis. However, intratumoral hemorrhage often is contained by a pseudocapsule, which prevents fascial plane tracking and subcutaneous ecchymosis, thus providing a diagnostic clue. Magnetic resonance imaging and ultrasound studies may not accurately diagnose questionable lesions. Diagnostic delay or inappropriate treatment may result if patients do not receive appropriate followup, biopsy (usually open), or referral whenever the diagnosis is in doubt.