Primary bone lymphoma - experience of oncological orthopaedics department in Brzozów.

BACKGROUND Primary bone lymphomas are very rare. The diagnosis is based on a histopathological examination and imaging studies where other disease foci should be excluded. The lymphomas are most often found in the axial skeleton, pelvis, femur and humerus. The tumour causes extensive lytic bone destruction with soft tissue infiltration. Surgical treatment is currently not used routinely. The aim of this study was to present five clinical cases and their most characteristic imaging features. MATERIAL AND METHODS Over the last three years, 1327 patients with bone tumours have been hospitalized in the Oncological Orthopaedics Department in Brzozów, and most of these tumours (1184) were metastatic cancers. A total of 57 primary malignant bone tumours were diagnosed, of which five fulfilled the diagnostic criteria of primary bone lymphomas. Patient age and tumour sites varied. All the tumours were large, infiltrated soft tissues and caused osteolysis. No periosteal reactions or sequesters were observed. Two patients were treated surgically by radical resection and implantation of a prosthesis. The indication for surgery was tumour location enabling R0 resection. All patients received chemotherapy and radiotherapy. They have been followed up at the haematological and orthopaedic clinics. There is currently no evidence of generalized disease. RESULTS The most characteristic feature of bone lymphomas is extensive osteolysis with soft tissue infiltration. The absence of false capsules helps distinguish lymphomas from sarcomas. No bone sequesters or osteosclerotic lesions described in the literature were observed in imaging examinations at our centre. Discussion. Diagnosis of a primary bone lymphoma is difficult as the tumour often resembles metastatic lesions. Secondary bone involvement is particularly difficult to differentiate from multifocal lymphoma. The Coley criteria are useful in diagnosis. If radical resection is possible, surgical treatment significantly improves prognosis. Radiotherapy has been associated with frequent recurrences of generalized disease and it is postulated that it should only be employed in palliative patients. CONCLUSIONS 1. Primary bone lymphomas are rare tumours. 2. Imaging studies characteristically show extensive lytic bone destruction with soft tissue infiltration. 3. No sclerotic lesions or periosteal reactions were observed. 4. Surgical treatment should be performed when radical tumour resection is possible.