Imaging of giant cell tumor and giant cell reparative granuloma of bone

Abstract

Aims: o Discuss imaging features of giant cell tumor of bone and giant cell reparative granuloma o Discuss the role of different imaging modalities in diagnosis of giant cell tumor and giant cell reparative granuloma. o Explain the pathologic basis for radiologic features of giant cell tumor and giant cell reparative granuloma o Discuss types of malignant giant cell tumors with their imaging features. o Describe the traditional treatment of giant cell tumors and list the common post operative complications Materials and Methods: This retrospective study of 10 patients was conducted in Shri M.P.SHAH Medical college and GURU GOBIND Singh hospital, Jamnagar. Observations: The most common site for giant cell tumor in our observation was femur; some rare locations for giant cell tumor observed were flat bones like frontal bone and acromion; the single case of malignant giant cell tumor involved the patella. On plain radiography, majority of cases of giant cell tumor showed a well defined, eccentric, lytic lesion with non sclerotic border involving the epi-metaphyseal region of long bones with sub articular extension in patients with closed physis. On MRI, majority of patients showed well defined lesions which appeared hypointense on T1WI and heterogeneous predominantly hyperintense on T2W and STIRWI. The heterogeneous signal on T2WI reflected the inherent tissue inhomogenity.The single case of malignant giant cell tumor in our study, involved the patella in a middle aged female. It presented as expansile lytic lesion involving the patella with destruction of the cortical outline and soft tissue mass replacing majority of the bone. It showed intense enhancement with areas of central necrosis on post contrast scans. It also caused destruction of the anterior tibial cortex with minimal extension into tibial matrix. There was post operative recurrence in one patient who was treated with curettage and cement placement. The single case of giant cell reparative granuloma showed a well defined multiloculated expansile lytic lesion in right temporal bone. On MRI, it appeared hypointense on T1WI and heterogeneous on T2WI and showed homogenous moderate post contrast enhancement Conclusion: Giant cell tumor of bone is typically benign lesion but may demonstrate aggressive imaging features or fluid fluid levels. Traditional treatment of giant cell tumor is associated with high recurrence rate. Giant cell reparative granuloma is a reparative process rather than a true neoplasm. It presents with imaging findings quite similar to giant cell tumor. However, it commonly affects the mandible, maxilla, small bones of hand and feet.