Extra-nodal non-Hodgkin’s lymphoma (ENHL) affecting oral cavity misinterpreted as painful dental infection, delaying diagnosis − case report

An 83-year-old woman was referred with a painful, broad-based right facial swelling. It was firm to palpation, with mucosa intact. Symptoms had been present for about six months, during which time she was treated with multiple antibiotics, endodontic therapies, and extraction of all right maxillary molars. Her medical history included hypertension, arthritis, depression, and colon carcinoma treated four years previously. Orthopantomography revealed a poorly demarcated area of low bone density affecting the entire molar region, with diffuse opacification of the maxillary sinus and with destruction/perforation of alveolar cortical bone. A CT scan showed a soft tissue mass filling the sinus and destroying the sinus floor and underlying alveolus, also the right facial alveolar cortex, with broad proliferation outside that cortex. Incisional biopsy revealed a proliferation of large lymphoid cells (kappa B-cells), consistent with follicular lymphoma. Tissue was strongly immunoreactive to CD20, CD10 and BCL2, with partial reactivity to Ki67 and with a CD21 reactive dendritic meshwork around neoplastic cells. With this diagnosis, a PET scan was performed, showing involvement of the right submandibular, bilateral axillary and hilar lymph nodes, as well as scattered retroperitoneal nodes. The patient was referred to the regional cancer center, where surgery and chemotherapy were scheduled.