Primary ovarian lymphoma: A case report

•Primary ovarian lymphoma is a rare ovarian tumor that should be part of differential diagnosis for adnexal masses.•Ovarian lymphoma has no distinguishing features on workup.•Fertility sparing surgery is feasible if lymphoma identified preoperative or intraoperatively. While Non-Hodgkin Lymphoma (NHL) often involves the ovaries at time of autopsy, it is rarely present at the time of diagnosis. Here we present a case of a 20-year-old who presented with a large adnexal mass and elevated B-HCG, CA-125, and LDH. The patient underwent exploratory laparotomy, and frozen section of the left ovarian mass was suspected to be a dysgerminoma. Final pathologic diagnosis was Ann Arbor stage IVE Diffuse Large B-Cell Lymphoma, germinal center subtype. Patient is currently undergoing chemotherapy and has received the 3 of a planned 6 cycles of R-CHOP.