Primary extranodal non-Hodgkin's lymphomas of the head and neck account for 10-20% of all non-Hodgkin's lymphomas. Primary tonsillar lymphoma accounts for less than 1% of head and neck malignancies, although the tonsil is the most common primary extranodal site of head and neck non-Hodgkin's lymphomas. In this study we analyzed our cases of tonsillar lymphoma treated in our institution during the last 10 years to compare the finding of this study with those of previous studies. We reviewed the cases of tonsillar lymphoma treated in the Radiation Oncology Department of Shiraz University from 1992 to 2002. Clinical data were obtained from patients' files. The patients were treated by combined chemotherapy [a median of six cycles of a CHOP regimen (cyclophosphamide, doxorubicin, vincristine, and prednisolone)] and radiation therapy (40-50 Gy to the primary site and neck). Chemotherapy mainly preceded radiotherapy, although the sequence of radiotherapy and chemotherapy was determined by individual physicians and patients' choice. Surgery was used mainly to establish the diagnosis, and tonsillectomy was performed for localized small lesions. Between 1992 and 2002, 19 patients with stage IE (10), IIE (7), and IIIE (2) disease were treated. Median and mean age was 48 and 44 years (range: 22-76 years), respectively, at the time of diagnosis, with a male to female ratio of 1.2:1. The vast majority of patients presented in early stages with aggressive histology. High-grade tumors seemed to affect mainly young people (p=0.226). Diffuse large B-cell lymphomas were the most prevalent. Male patients were significantly younger than females (p=0.021). The patients were treated by combined chemotherapy and radiation therapy. All patients achieved and maintained complete remission with a median of 60 months relapse-free survival and a 5-year cause-specific survival rate of 100%. All patients developed some degree of oropharyngeal mucositis. Three patients (16%) experienced grade 3 or 4 neutropenia. Mild (grade I) xerostomia remained persistently in four patients (21%). A late fatal side effect was observed in one patient who developed radiation-induced sarcoma 7 years after initial diagnosis and died 8 months later without evidence of recurrent lymphoma. Complete follow-up was obtained in all patients. The follow-up period ranged from 18 to 141 months with a median of 60 and a mean of 60.4 months. At the time of last follow-up, all patients but one were alive. Age, sex, stage, bulk of disease, performance status, number of chemotherapy cycles, number of involved sites, histologic subtypes, and radiation dose were analyzed as prognostically significant for disease-specific survival in our cases. Significant prognostic factors were not identified by multivariate analysis. Combined chemotherapy and radiation therapy is safe, highly effective, and probably curative for most patients with primary tonsillar lymphoma.
