Leiomyoma With Massive Lymphoid Infiltration: 2 Cases With Lymphocytic Vasculopathy and Angiocentric Germinal Centers.

Uterine leiomyoma with massive lymphoid infiltration is characterized by a dense lymphoid infiltrate and germinal centers sparing the adjacent myometrium. Only few reports describe this entity and its etiology is unknown. This rare lesion may also exhibit lymphocytic vasculopathy but this has only been reported in the setting of GnRH agonist exposure. We report 2 cases of uterine leiomyoma with massive lymphoid infiltration in which only 1 patient was exposed to GnRH agonists. In both cases, histopathologic analysis showed thick-walled vessels with swollen endothelial cells showing evidence of intramural lymphocytic infiltration, red blood cell extravasation, and medial edema. This constellation of findings represented frank vascular damage and lymphocytic vasculopathy. Our findings suggest that lymphocytic vasculopathy in these lesions may be secondary to factors other than GnRH agonists. Furthermore, both cases showed an angiocentric disposition of germinal centers that has scarcely been alluded to in prior reports. This finding may provide a clue in accurately recognizing leiomyoma with massive lymphoid infiltration. Recognition of this lesion will allow one to avoid mistaking it for mimickers such as inflammatory myofibroblastic tumor, lymphoid malignancies, or other inflammatory processes.