Primary non-germinal center B-cell-like diffuse large B-cell lymphoma arising from the patella

Successful Outcome of Patellectomy Plus Chemotherapy for Primary Bone Lymphoma of the Patella: A Case Report and Literature Review

Primary bone lymphoma (PBL) is a rare but distinct clinicopathological disease, usually occurring in the pelvis, spine, and ribs. To date, only a few cases have been reported as beginning in the patella. Due to the lack of clinical evidence, the optimal treatment strategy has not been established. Here, we report a case that presented unexplained right knee pain. The case was diagnosed with the non-germinal center, diffuse large B cell lymphoma in the patella by imaging examinations and bone biopsy. Then, the patient received a patellectomy and eight cycles of R-CHOP chemotherapy. After treatment, the patient achieved a favorable prognosis and satisfactory functional recovery.

Primary bone lymphoma of patella: A case report and review of literature

Primary bone lymphoma (PBL) is rare bone disease that accounts for very small number of all primary bone tumors. Among the described sites of PBLs, the patella is an extremely rare example. To date, only a few cases of PBL affecting the patella have been reported. Clinically, these tumors have very similar presentation of pain, decreased range of motion and swelling and, sometimes, pathologic fractures. On radiographs, skeletal lymphoma commonly manifests as osteolytic lesions with ill-defined margins affecting the metaphysis of axial long bones. We present a rare case of patellar adult T-cell lymphoma/leukemia in a 58-year-old female who presented with left-knee pain and swelling. Computed tomography and magnetic resonance imaging revealed diffuse marrow replacement by a lesion with aggressive features. PET scan demonstrated neoplastic range hypermetabolic FDG uptake within this lesion. Ultrasound-guided biopsy was consistent with PBL.