Just tell them! Tell your ex-fiance as well. He has the right to decide for himself (you can only decide for you not anyone else). Cutting him out is not doing him a favor. Really (I know from my own experience of being on his side of things)!! He may run but he may surprise you. Prior to surgery (hysterectomy with tubes, ovaries, parametrium and top end of vagina removed 3/29/17) I had endometrial cancer (extending into the upper cervix) so, althoug some of the details are slightly different the majority of issues are not. I have still 5 sessions of brachytherapy to the vagina to go. When you tell your dating or potential dating partners is not something that is easily kept to a rigid schedule. In order to keep from being evasive (which is not a good thing to be, in my opinion) you may have the issue staring you both in the face earlier. In the last monthe I have had "the cancer conversation" two times with two different men prior to even meeting them in person (met through reputable online services). I didn't pull punches and told them the potential long-term side effects of the radiotherapy (not looking forward to this--just had my consultation appt. with rad onco yesterday morning). At the point in our messages when it seemed clear that there was some potential I said that if they were going to seriously consider dating me that there was something I had to tell them...and that it was a very difficult thing for me to say. Then, I told them but framed it so it was realistic but not doom and gloom. I told them that my chances of cancer reoccurrence were... and that the lifetime chances of any man getting prostate cancer (to make the issue equivalent) was 12.2%. (I got this from a US gov't cancer site. Of course this is a lifetime average starting out with 0% chance when very young and increasing with age--the average being 12.2%.) To get to the punch line here: both men said that they were still in! These men are in their fifties so are not children so, maybe, that makes a difference (I just turned 67 myself!). There is more hope than you might think. I had gone through all kinds of guilt even being on the dating sites--I joined both befoe my diagnosis--but stopped feeling guilty when I realized that grown men are capable of making their own decisions and they may get or have had cancer, themselves, or a friend or family member...etc. Just do it! Once you say the truth--and it IS very hard to say--regardless of how they respond, your dread is gone.