Background: Primary lymphomas of the endometrium are extremely rare. Diagnosis is difficult, especially when the neoplasm is originally evaluated on a cervicovaginal smear. When lymphomas involve the endometrium, the cervix is three times more likely to be the primary site rather than the endometrium. Two of the symptoms of primary lymphoma of the endometrium are abnormal vaginal bleeding and an abdominal or pelvic mass.
Cases: Case 1 was a 36-year-old, obese, black female with an abdominal mass and recent onset of ascites. The second case was a 31-year-old, obese, black female with a history of menometrorrhagia. The cytologic findings in both cases revealed an individual cell population, high nuclear/cytoplasmic ratio, small nucleoli and coarsely granular chromatin with some chromatin clearing. Endometrial currettings showed a histologic pattern of malignant non-Hodgkin's lymphoma, diffuse, large cell type. Immunoperoxidase staining was positive for leukocyte common antigen.
Conclusion: Two cases of lymphoma of the endometrium were diagnosed first by a cervical cytologic smear, supported by a positive body cavity fluid in one case and histology in both. The differential diagnoses included various inflammatory lesions, small cell carcinoma, endometrial stromal sarcoma and granulocytic sarcoma.