I just had a unilateral mastectomy due to recent diagnosis for breast cancer (DCIS grade 3 with less than 1mm micro-invasion, 5 lymph nodes removed and tested negative, 0/5, BRAC 1 and 2 gene tested negative). The oncologist said I do not need chemo or radiation, but want me to take Tamoxifen for at least 5 years. Now I am very struggling on whether to take it or not. I really need other patients' help on deciding if I should take Tamoxifen or not. The only reason that I don't want to take the Tamoxifen is because I am scared about getting the possibility of having endometrial cancer, sometimes, my endometrial thickness is already a concern by the radiologist, thus I am desperately hoping to seek real-life experiences and advice from anyone here who has already gone through this.
My questions are: If you have taken Tamoxifen for years, have you suffered from any significant side effects (particularly uterine or endometrial cancer)? If you had opted not to take Tamoxifen years ago, do you still think it's a good decision or a decision you regret about now? Your views and advice are greatly appreciated!