Background: An extranodal lymphoma in oral cavity represents less than 5% of oral malignant disease, commonly arising in submucosal tissues of gingiva, palate, and tongue. The lymphoma in the jaws is sometimes difficult to be diagnosed because of absence of specific signs and symptoms, as well as their low frequency. Here we present our experiences of the primary extranodal lymphoma which involved some difficult cases to be diagnosed.

Methods: This study reports 7 cases of the extranodal lymphoma in oral cavity or maxillofacial regions. All of the patients were proven pathological diagnoses with biopsy specimens. Data investigated were patients’ characteristics, staging, pathological diagnoses, image findings, and treatment courses.

Results: Four patients were male and 3 female with a median age of 63 years. Chief complaints were gingival swelling in 5 patients and pain in 2, presented with lower lip paresthesia in 2. Primary sites of disease were bone of maxilla in 1 patient and mandible in 2, upper gingiva in 1, floor of mouth in 1, maxillary sinus in 1, and palatal soft tissue in 1, respectively. Two of those were clinically diagnosed inflammatory diseases at the time of their first present. Histological diagnoses from biopsy specimens showed the diffuse large B-cell lymphoma in 4 cases, the adult T-cell lymphoma/leukemia in 2, and Burkitt’s lymphoma in 1. Staging included stage IAE in 2 patients, IIAE in 3, IVA in 1, and IVB in 1. Four patients were died of the disease during a follow-up period, although 1 of them had a complete response after chemotherapy.

Conclusions: A careful examination is necessary to be diagnosed early, which results in a better prognosis. Moreover, maxillofacial surgeons are needed to keep following up the patients to recognize any recurrences after completing their treatments.

Key words: lymphoma; oral cavity; jaw