Hi unique, are your parents in your lives? I would talk to them. I know with privacy laws you get advice from her doctor but you can still voice your concerns to her doctor under confidence, he can't talk to you about her health tho but he should be aware of things. Something doesn't sound right with the green stuff, 6 years with cancer w/o treatment is odd too because it would spread. It her life and if that's what she wants there is not much you can do about it, but her doctor should know about breast issues definitely.
Your story is a very sad one and I am so sorry you are having to deal with this situation. You must realize that you are pretty much helpless unless you can somehow convince your Sister that she is killing herself. We must also admit that we as human beings have the right to accept or refuse any and all medical treatment no matter what the condition; unless of course there is some mental condition that makes the person incompetent which would have to be handled in the Courts and a Guardian appointed. Of course she more than likely has had a spread of the cancer cells in this length of time and the causing of the breast discharge can have nothing at all to do with the cancer. Breast discharge can be produced almost any time the breast is squeezed as a signal is sent to the brain when the breast is squeezed which produces some type of discharge. I know that many believe surgery will hasten the spread of cancer cells but of course this is far from true. I wish I could offer a solution for you but like I said initially, if she refuses treatment or even to accept the diagnosis of cancer there isn't much you can do. I suppose you could inform her present Physician of her true condition but I'm surprised that it wasn't discovered when she had filming done in the hospital. I'm not really sure that such action on your part would even be ethical but it might be worth a try. If her Dr.s don't know of the cancer diagnosis are you sure that this is actually what was found 6 years ago ?? I'm curious as to how you found out about this ... just wondering as I'm certain her breast would show some evidence of a lump which would be easily noticed by any medical practitioners who saw her in the hospital recently. Truly I am a bit suspect of this diagnosis being hidden for 6 years .... there had to be filming and a biopsy done at that time and these things would be in her medical records. If you prefer not to post additional information on the forum here you are welcome to contact me by Private Message. I find this situation very interesting and would like to follow it if possible. Thanks ...