Giant cell tumor (GCT) are well expansile, osteolytic lesion, with narrow transition zone at epiphysiometaphyseal region, commonly seen at ends of long bones accounting for approximately 5% of all primary bone tumors in adults. GCT in sacrum is the fourth commonest site after long end of bones, knee and radius, accounting for 1.7-8% of all GCTs. Primary sacral tumor is rare and have incidence rate of 1 in 46,000 hospital admissions according to Ross and 1 in 30,000 according to Dockerty. GCTs are more common in Asia about 20% when compared to 4-5% in West.
As per the World health Organization (WHO) GCT is termed as “an aggressive potentially malignant lesion. About 80% of GCTs have a benign course with a recurrence rate of 20%-50% out of which only 10% may undergo malignant transformation and 1%-4% gives rise to pulmonary metastases. They have also been reported to metastasize to regional lymph nodes, the mediastinum, pelvis scalp, bone and paraaortic nodes. Herein we report a case of GCT of sacrum in a 35 year old female patient who presented with dull aching pain with no radiation making it unlikely to diagnose.