Summary

Multicentric giant cell tumours (GCTs) are very rare and account for less than 1% of all GCTs of bone. We report a case of a young woman with metachronous multicentric GCTs with 5 documented lesions in the same lower limb. The initial lesion started during the first trimester of pregnancy around her right pelvis, which rapidly progressed as a painful swelling with gradually restricted mobility of her right hip joint. The radiological appearance of this tumour was that of a GCT and biopsy confirmed the diagnosis. The role of positron emission tomography (PET) has been highlighted to detect occult lesions. A possible hormonal correlation for these tumours has been discussed. The patient was managed successfully by an aggressive surgical approach for knee and talar lesions, whereas repeated embolisation and denosumab injections were given to treat her pelvic lesion.