Abstract
BACKGROUND: The differential diagnosis for a lytic bony lesion and soft tissue mass in a young individual includes primary bone tumours, soft tissue tumors, small round blue cell tumours, and rarely Langerhans-cell histiocytosis, and non-Hodgkin lymphomas. CASE REPORT: We report a young patient, who presented with a large expansile solitary lytic lesion involving the scapula and soft tissue. Immunohistochemistry on the core biopsy confirmed a diagnosis of diffuse large B-cell lymphoma. The positron emission tomography revealed fluorodeoxyglucose avid lesion involving left scapula and soft tissue around it. Solitary axillary lymph node SUV max 3.1 was also reported, and no other nodal involvement. The patient was managed successfully with chemotherapy and involved site radiotherapy. CONCLUSION: DLBCL involving bone and soft tissue is rare and can mimic sarcoma, particularly in young patients. This case underscores the importance of histopathological evaluation in atypical lytic lesions. Timely diagnosis and treatment led to sustained complete remission.