Which type of lesion is commonly associated with jawbone involvement and is described as a clonal plasma cell proliferation?

• A. Multiple myeloma
• B. Ameloblastoma
• C. Osteosarcoma
• D. Langerhans cell histiocytosis

Answer: (A)

A lesion described as a clonal plasma cell proliferation in the jawbone points to multiple myeloma, a systemic plasma cell neoplasm. In multiple myeloma, a single clone of plasma cells expands and infiltrates bone, leading to bone destruction and characteristic jaw involvement such as punched-out radiolucencies, tooth mobility, and bone pain. This distinction matters because it differentiates from other jaw lesions that are not driven by a monoclonal plasma cell process: ameloblastoma is a benign odontogenic tumor, osteosarcoma is a malignant bone tumor that produces osteoid, and Langerhans cell histiocytosis involves proliferation of Langerhans cells rather than plasma cells.