This is really an unusual scenario considering that you only had DCIS before. Indeed cancer never fails to surprise us and sneak past even the best medical care.
The fact that your tumor is ER positive, then I believe that the initial approach of hormonal treatment is reasonable and sound. The removal of your ovaries would also cause favorable effects as you would lessen significantly your circulating amounts of estrogen. Other hormonal treatments that you can ask your doctor while waiting for the ovary removal would be drugs like leuprolide or goserelin, as this would also suppress ovarian production of estrogens.
If all hormonal drugs fail, then chemotherapy is indeed an option. chemotherapy may also be necessary if there is critical tumor bulk such as that causing so much pain, or compressing vital structures or organs. Since you have a stage IV systemic disease, then i believe that radiation should only be given for critical tumors causing severe pain or bone deformities, or likewise compressing other organs.
Regarding diet, I believe there has been no standard recommendations save for avoidance of too much animal fat.
Thank you for such a fast response! So far the main tumor isn't causing as much pain as it was - so I am hopeful that it is shrinking. And yes - my doctors are all stumped by my diagnoses. The only thing they can think of is that I had an invasive cell 9 years ago and it was hidden. I am a mystery to them – even my DCIS presented in a very stage way – no tumor – just a cigar shape of what appeared to be fatty breast cells. They are still talking about it 9 years later.
My hope is that it took 9 years to show signs – so it is slow growing and will continue to do so.
My last question is the tumor makers – is 670 high, normal, or low for stage IV?