Dedifferentiated umbilical metastases from low grade endometrioid endometrial adenocarcinoma complicated by super-obesity : a case report

Introduction: Umbilical metastases are uncommon and rarely associated with endometrial cancer. In this report we describe a unique case of a patient with low-grade endometrioid adenocarcinoma (EAC) who developed an umbilical metastasis containing dedifferentiated endometrial carcinoma, in the context of super-morbid obesity with a body mass index (BMI) of 80 kg/m2. Presentation of case: A 55-year-old female with atypical endometrial hyperplasia was treated with progestogens whilst attempting weight loss prior to definitive surgery, given the impact of her obesity on surgical risk. She progressed to grade 1 EAC of the uterus and then to metastatic disease in the umbilicus and inguinal lymph nodes. After adequate weight loss, cytoreductive surgery was completed via robotic hysterectomy and bilateral salpingoophorectomy (BSO) and resection of metastatic disease. Differing histological grades were seen across all disease sites with dedifferentiated endometrial carcinoma at the umbilicus. Immunohistochemistry suggested a common uterine origin due to loss of MLH1 and PMS2 proteins. Discussion: There are no clear management pathways for the rare umbilical metastases related to endometrial cancer. Our patient's significant obesity complicated their clinical course and highlights the risks of progestogen therapy whilst attempting weight loss prior to definitive surgery for low-grade EAC. Differing grades of disease across metastatic sites in EAC is rare and may reflect the recently recognized intratumoral genetic heterogeneity in endometrial cancers. Conclusion: Management of umbilical metastases should be individualized to patient factors and local resources. More research is needed into pathways of care for women with low grade EAC with obesity preventing routine surgical management.