Diffuse Large B-Cell Lymphoma of the Frontal Sinus: A Case Report.

Diffuse large B-cell lymphoma (DLBCL) is the most common type of Non-Hodgkin Lymphoma (NHL). It often involves the gastrointestinal tract, head and neck, and skin, but virtually any tissue or organ can be affected. The primary NHL of the nasal cavity and paranasal sinuses are extremely rare, causing diagnostic and therapeutic difficulties. We present the case of a 49-year-old woman with a 4-week history of diplopia and right superior eyelid swelling. Clinical, radiological, and histological examination led to the diagnosis of DLBCL of the right frontal sinus with anterior invasion of subcutaneous soft tissues and posterior intracranial involvement of the frontal region. She underwent three cycles of MATRIX chemotherapy, three cycles of R-DA-EPOCH, and CAR-T therapy. Unfortunately, treatments were unsuccessful and the patient died 11 months after diagnosis. In conclusion, an early diagnosis of DLBCL of the frontal sinus is difficult as it is often confused with other nasal pathologies. This causes a delay in treatment.