Primary endometrial extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue type

Introduction Primary lymphomas of the female genital system are rare and represent about 2% of extranodal lymphomas and about 0.5% of malignant gynecological diseases, which occur in only 0.5% of cases in the cervix and uterine body. Mucosa-associated lymphoid tissue (MALT) lymphoma represents a rare variant of the primary genital lymphoma. Case outline This paper presents the case of a 45-year-old patient who visited a gynecologist due to abnormal menstrual bleeding within the previous three years and bloody excrement between menstrual bleedings. The ultrasound examination raised doubts about endometrial polyps, thus the fractional exploratory curettage was performed. Histologically, a dense infiltration of stromal endometrium was demonstrated in the endometrium through fine-tuned lymphocytic cells that were highly positive for immunohistochemical markers CD20, CD79a, CD45, positive for CD5 in up to 5% of tumor cells, negative for Cyclin D1, CD10, and bcl-2. The proliferation marker Ki-67 was expressed in approximately 15% of the lymphocytic tumor cells. The patient's uterus and adnexa were surgically removed and she did not receive any additional therapy. After a 3.5-year follow-up, the patient has been without a relapse of the disease. Conclusion Although non-Hodgkin's lymphomas of the genital organs, especially the MALT type of non-Hodgkin's lymphoma, are extremely rare, they should also be considered as a differential diagnosis in women with menometrorrhagia and the ultrasound image of the endometrial polyps.