Background and objectives: Primary malignant lymphoma in the parotid gland is rare and seldom described in the literature. We studied the medical history and outcome of seven patients with a primary malignant parotid lymphoma. We looked for prognostic variables and for different behavior of these lymphomas in comparison to lymphomas in the usual sites.
Methods: Between 1985 and 1995, we conducted a retrospective study of the medical histories of malignant parotid tumors operated at our hospital. There were 18 malignancies, of which 7 were primary malignant lymphomas. We classified them according to Rosenberg et al. [Blood 1994;84: 1359-1392]. Outcome and survival time were compared with malignant lymphomas in usual sites. Further we looked for possible prognostic factors.
Results: We found an unusually high percentage of primary malignant lymphomas in the parotid gland in our series: 38% of all malignancies. Histological workup showed one Hodgkin lymphoma, two marginal zone B-cell non-Hodgkin lymphomas, two lymphoplasmocytoid non-Hodgkin lymphomas, and two follicular non-Hodgkin lymphomas. The clinical course of these lymphomas is comparable to that in lymphomas in the usual sites.
Conclusions: Primary malignant lymphomas in the parotid gland have no different behavior compared to lymphomas in usual sites. There are no prognostic variables that distinguish a malignant lymphoma in the parotid gland. The only difference is a rather difficult operation to obtain a histologic specimen.