Mistaken Sacral Giant Cell Osteosarcoma

A 29 - year - old female patient presented with complaints of low back pain radiating to bilateral lower limbs with parasthesia?s and unable to sit since three months. The pain was insidious on onset, gradually progressive which did not relieve even on medication. The patient was advised X ?ray LS spine AP & lateral view shows an ill - defined lytic area with adjacent soft tissue shadow & advised MRI for further evaluation. MRI LS spine was done which showed large expansile lytic lesion in sacrum, coccyx with extensive soft tissue component. To evaluate further we did biopsy & came as giant cell tumour of sacrum. Surgical resection of the tumour was done partly as the complete tumour resection was not possible due to pelvic adhesions. Resected tissue sample sent again for histopathology and reported as giant cell tumour. Patient came for follow up after three months with extensive tumour spread to pelvis & lung metastasis. Biopsy performed again & came as Giant cell rich Osteosarcoma.