Extranodal non-Hodgkin's lymphoma of the oral tissues. An analysis of 20 cases.

A series of 20 patients with extra-nodal non-Hodgkin's lymphoma (ENHL) of the oral cavity was analysed with the emphasis on histopathological variability and prognostic factors. The current diagnostic schemes as devised for nodal NHL proved also to be useful in diagnosing ENHL in the oral cavity. With respect to histopathology, intra-oral ENHL differs from nodal NHL in a lower incidence of nodular growth pattern and a relative predominance of the lymphoma sub-type with large vesicular indented nuclei. These are features, however, that are shared with ENHL in other body sites and thus are not unique to the oral location. Another salient histological feature was the presence of proliferating bizarre spindle cells with formation of whorling bundles of reticulin, thus creating a pseudosarcomatous growth pattern in some cases. The clinical stage proved to be the main discriminating factor between those who survived and those who died of their lymphoma. Of the patients who were in stage IE on admission, 70% survived as opposed to only 20% of those who were in stage II or IV. A better prognosis for cases with soft tissue involvement as opposed to intraosseous lymphoma is probably due to a consistently lower clinical stage in the former group. The prognostic value of the clinical stage emphasizes the importance of adequate clinical staging procedures.