@lesleyjt I noticed you are on a couple other pages since your diagnosis, welcome to the club you never wanted to join. You will meet the nicest people here. 😁
Sometimes a doctor will recommend shrinking the tumor with chemotherapy first. A few reasons might be aggressive looking cells in the tumor. The large size of the tumor, or it might be something completely different. This has been studied extensively and certain cancers do have better outcomes with this plan.
I know the situation is a little different but here is a link to another recent post about chemo before surgery.
https://connect.mayoclinic.org/discussion/lymph-nodes-surgery-first-or-chemo-first/
Did your doctor explain a reasoning behind this choice? Are you comfortable asking?