Introduction: Involvement of bone by lymphoma usually occurs in the setting of widespread systemic disease. The primary bone lymphoma (PBL) is a rare entity, accounting for 3 to 7% of primary malignant bone tumors and less than 2% of all lymphomas. The Multifocal forms are even rarer and can be confused with bone metastases. The diagnosis is guided by the clinic and radiology, but only the histology confirms accurate diagnosis. Observation: We report a rare case of primitive iliac lymphoma in a 58-year-old man. The pathological study was in favor of a diffuse large B-cell lymphoma. An 18 fluorodesoxyglucose (FDG) positron emission tomography computed tomography (PET/CT) performed as part of the staging assessment revealed multifocal bone involvement. Conclusion: This case highlights the importance to evoke the diagnosis of primary bone lymphoma, even if it presents in an unusual site, as well as the value of metabolic imaging in assessing the extent of the disease.

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