Two cases of primary malignant lymphoma of uterus. An immunohistochemical study.

Malignant lymphoma originating from the uterus is reported extremely rarely. Since Epperson described the first case in 1950, no more than about fifty cases have been reported world wide. Here we report two cases of primary uterine malignant lymphoma diagnosed according to Fox and More's criteria. One of the patients was a 39-year-old housewife who suffered from atypical genital bleeding. Hysterectomy was performed and histological examination revealed malignant lymphoma, diffuse, medium sized. Upon immunohistochemical examination, the tumor cells were positive for several antibodies against B lymphocytes and also for CD74 (LN2). The patient is currently alive and well after surgery. The other patient was an 80-year-old housewife who suffered from abdominal discomfort. Clinical examination revealed abnormal enlargement of the uterus and obstruction of the urinary tract. Eight days after admission, she died of general consumption, and autopsy was performed. The uterus was markedly enlarged with a tumor, which extended to the serosa of the intestine and the peritoneum, involving one lymph node. However, there were no other tumors in other organs examined. Histologically, the tumor cells were distributed diffusely throughout the entire uterine wall and were medium-sized lymphoid cells. Immunohistochemical analysis revealed a B-lymphocyte nature, with positivity for L26, CD20, CD22, CD74 (LN2) and sIgD (surface IgD), but both T lymphocytic and histiocytic markers were negative.