New to site Oncotype issue...help

Pepper12

New to site and was diagnosed with invasive breast cancer end of March. Had bilateral mastectomy in April. Was told by surgeon margins were good. 2 tumors removed biggest one 4.6 cm. Saw oncologist first of week . Onco score 19. Normally would not need chem With this score. Oncologist  said due to size and grade 3 she would reach out to colleagues and call me with thoughts on needing chemo. She was not sure how big an impact chemo would have. Anyone experience this ? Don't won't to undertreat but definitely don't want to over treat. Will be having radiation and hormone therapy. Thank you for your support.