4 rounds vs 6 chemo Treatment

Hi,

My oncologist wanted me to join a trial but I decided not to due to the side effects. When I told him I wasn't joining the trial he told me that if he would have known that, he would have given me 6 rounds of chemo instead of 4! Now I'm afraid I didn't get enough chemo! I had a 2.5 centimeters mixed grade 1 and 2 tumor as well as a 9 mm grade 2 in situ tumor. Both in the same area. I had 5 sentinel nodes removed with 2 positive for cancer. 3 and 4 mm. My tumors were estrogen positive and HER2 negative. I've read a lot of studies that say 4 rounds is as good as 6.....my Ki67 was very low. 8%, but my R53 was 40%. Anybody out there with similar diagnosis that received 4 rounds? Feeling scared....

Thank you for responding.