Endometrial Cancer Symptoms: What To Look For? Endometrial cancer is serious cancer that affects the endometrium, the layer of tissue that lines the uterus. Suppose you or a loved one is experiencing any of the following symptoms. In that case, it may indicate endometrial cancer: unusual vaginal bleeding, pain during or after sex, infertility, heavy menstrual periods, shortness of breath, fatigue, and more. This blog post will explore all the signs and symptoms of endometrial cancer and how to identify it early on.