Hello @lnw! My mass was 7 mm for invasive DCIS. My oncologist said if the mass was less than 5 mm, she would not have recommended chemo. However, she has recommended that I have 4 rounds over a 12-week period. I have a few weeks to decide.
Subsequently, my cancer was not estrogen fed. Based on what you have stated the chemo and inhibitor treatment would be the best outcome. A 2nd opinion may be helpful in your case as well.
Best wishes.