Malignant lymphoma of parotid associated with Mikulicz disease (benign lymphoepithelial lesion).

Benign lymphoepithelial lesion (Mikulicz disease) is generally regarded as an inflammatory disorder of unknown aetiology, characterized by epimyoepithelial islands, and unrelated to malignant lymphoma. Five cases have been collected which show evidence at the same site of both Mikulicz disease and a malignant lymphoma. The latter took the form of reticulum-cell sarcoma or Hodgkin's disease. The two diseases were discovered simultaneously or the malignant lymphoma was detected at a subsequent date. The probable sequence of events is discussed. These cases are regarded as one of the best illustrations in man of an autoimmune disorder being followed by the development of malignant lymphoma. It is concluded that so-called benign lymphoepithelial lesion is not always innocuous and an attempt is made to establish histological criteria which might be regarded with suspicion in a particular case.