The diagnostic value of fine needle aspiration cytology in Waldeyer's ring lymphomas.

Fine needle aspiration cytology (FNAC) is a well-established diagnostic technique for tumours in the head and neck area. In recent years FNAC has been established as an accurate and useful method for the diagnosis of nodal malignant lymphoproliferative disease. The purpose of the present study was to determine and evaluate the accuracy of FNAC in the diagnosis of primary malignant lymphoma of Waldeyer's ring. The cases of 29 patients suffering from tumours of the oro- and nasopharynx, in which the diagnosis of lymphoma was established by FNAC during the years 1991-1998, were collected and analysed. Twelve of the patients had a previous history of lymphoma, and FNAC was used to establish the diagnosis of recurrent disease. In 17 patients with no previous history of malignancy FNAC was used to diagnose primary extranodal non-Hodgkin's lymphomas (NHLs). In two patients FNAC failed to diagnose NHL. In all patients cytological findings were complemented and compared with those of a histopathological examination after open biopsy. In two cases a difference in the specific histological type of the lymphoma was noted. The findings from the present study (sensitivity 93.10% and positive predictive value 100%) indicated that FNAC is a useful and accurate method in establishing diagnosis of Waldeyer's ring lymphomas.