Non-Hodgkin's lymphomas include malignant conditions developing within lymphoid tissue, both lymph nodes and extranodal lymphoid tissue. Due to its rich lymphatic supply, the cervico-facial region is frequently involved: 10 to 15% of all NHL (1, 2, 8, 15), i.e. a similar incidence to primary GI involvement (4). The cervical glands and lymphatic structures of the Waldeyer ring are most often and most classically involved. The nasosinusal cavities may be involved, producing diagnostic problems which have to be resolved by the specialist (6). Between 1972 and 1989, 20 cases of NHL involving the bony cavities of the face were seen at the Centre Antoine-Lacassagne. These include the 15 cases reported below involving the naso-sinusal cavities.