RESUMO
Uterine leiomyomas are the most common benign tumors of the gynecological tract. Massive lymphocytic infiltration has been reported rarely in uterine leiomyomas and it has been described as a pathogenetic correlation with gonadotropin-releasing hormone agonists. Uterine leiomyomas with massive lymphoid infiltration have to be differentiated from non-Hodgkin lymphomas. We report a case of a woman without a history of gonadotropin-releasing hormone agonist treatment, who presented with a uterine leiomyoma that increased in size after the procedure of assisted in-vitro fertilization, and associated with massive nodular lymphoid infiltrate simulating, morphologically, a non-Hodgkin lymphoma. Uterine leiomyoma with massive lymphocytic infiltration is a very rare entity, probably of reactive significance, which has to be differentiated from diseases that need a systemic therapeutic approach.