An unusual presentation of metastatic chondrosarcoma on Tc99m MDP Bone scan.

Radionuclide bone scintigraphy with technetium-99m-methylene diphosphonate is the commonest procedure in nuclear medicine. It is an effective diagnostic tool in staging of primary bone tumours since long. It is not only helpful to confirm the radiologic features of malignant bone tumours but also demonstrates skeletal metastasis and soft tissue involvement. Computed tomography (CT) combined with single-photon emission computed tomography (SPECT/CT) give better insight to localize and categorize the lesions. We describe an interesting image of chondrosarcoma showing anatomical extent of primary tumour and multifocal uptake in the chest conforming to underlying widespread partially calcified pulmonary metastases.