CDK4/6 Inhibitor

Hi all - I have been treated for hormone positive stage 2 early breast cancer (grade 2/3) - lymph nodes were negative. I am on zoladex, exemestane and zoledronic acid. I am not on a CDK4/6 inhibitor. I understand this is because lymph nodes were negative. Is anyone in a similar situation but on a CDK4/6 inhibitor? I am happy with my current medication but have a small worry I may not have maximum protection