[Lymphoma of the Waldeyer's ring: experience at the National Institute for Cancer Research of Genoa].

Malignant lymphomas account for 3% of all malignant disease in the head and neck area. Twenty-five to fifty percent of all lymphomas arising in this region develop in extra-nodal structures, mostly in the Waldeyer ring. Lymphomas of the Waldeyer ring are comparable to any other lymphomas and prognosis is strictly related to stage and histology. The present paper reports 51 patients with malignant lymphomas arising in the head and neck (25 patients with Waldeyer ring involvement) recorded at the National Institute for Cancer Research, Genoa, Italy, from 1985 to the present. The characteristics of patients with Waldeyer ring involvement are comparable to those reported in the literature. Differences can be found in the median age (older in the present series) and in the incidence of Hodgkin's disease (8%). Patients were treated according to stage: stage I and II received radiation therapy and, in a few selected patients, this was combined with chemotherapy; stage III-IV received chemotherapy followed, in a few selected patients, by radiation therapy. In the present series, survival was related to the involvement of the Waldeyer ring: analysis has shown that survival is better in those patients with only nodal involvement. Nevertheless, these patients usually have a more advanced stage (p = less than 0.03). This finding is quite surprising since all the known prognostic factors are better in the Waldeyer group.