Solitary metastases from colorectal carcinoma in the absence of hepatic or pulmonary metastases are rare. These can have a diverse imaging appearance, particularly after chemotherapy. It is important identify patients with solitary skeletal metastases, as they have a better prognosis than those with multiple skeletal or visceral metastases. We describe an unusual case of a solitary metastasis to the femur in a case of colon carcinoma that went undiagnosed and later presented with imaging features of osteogenic sarcoma.
Adult ; Bone Neoplasms/diagnosis/radiography/secondary ; Carcinoma/*diagnosis/pathology/radiography ; Colorectal Neoplasms/*diagnosis/pathology/radiography ; Female ; Femur/radiography ; Humans ; Magnetic Resonance Imaging ; Prognosis ; Tomography, X-Ray Computed