Case Report

Cytokeratin-Positive Osteosarcoma Simulating Sarcomatoid Metastatic Carcinoma

Figure 1

(a) X-ray of the involved distal femur shows a mixed lucent sclerotic lesion with permeative borders involving the lateral distal femoral metaphysis. (b) MRI shows a bone lesion replacing the marrow in the LFC and distal metadiaphyseal junction with dark heterogeneous signal on T1W and brighter signal intensity on T2W sequences. (c) Perilesional edema is seen on the T2W sequences both in the intraosseous and periosteal regions. There was no definite associated STM. Maximal dimensions were just under 8 cm.
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