A successful intraoperative diagnosis of coexisting lymphoma and endometrial cancer

Background The coexistence of hematological malignancy with endometrial cancer is a rare phenomenon. We report a case of coexistence of endometrial cancer with follicular lymphoma which we suspected preoperatively and diagnosed during surgery by a multidisciplinary intraoperative assessment. Case presentation A 67-year-old woman was referred to our hospital due to a suspicion of an endometrial cancer. Endometrial biopsy revealed grade 1 endometrioid adenocarcinoma. MRI showed invasion of the tumor into the outer half of the myometrium, and abdominal CT showed para-aortic and atypical mesentery lymphadenopathy which was suspected to be metastasis of endometrial cancer or malignant lymphoma. Abdominal hysterectomy with bilateral salpingo-oophorectomy, pelvic and para-aortic lymphadenectomy, partial omentectomy, and mesentery lymph node biopsy for endometrial cancer were performed. The mesentery and para-aortic lymph nodes that were sent for frozen section analysis showed no metastasis of the endometrial cancer. We simultaneously conducted an unusual intraoperative emergent four-color flow cytometry and intraoperatively diagnosed a B cell lymphoma in the mesenteric lymph nodes. Because this multidisciplinary assessment, we were able to avoid an unnecessary intestinal resection. The final pathological diagnosis was an endometrioid carcinoma (G1, FIGO stage IA), with a synchronous follicular lymphoma. Conclusion Although a rare event in endometrial cancer surgery, it is necessary to be alert to the possibility of a synchronous lymphoma in cases of unusual site adenopathy.