I’m curious. What determines your cancer staging? Is it the initial breast biopsy pathology? The clinical pathology - oncologist’s assessment? Or the pathology after surgery?
From my understanding pathology after surgery is what determines it. I was given mine by my surgeon although she used the older method of staging and not the prognosis method. In the old method I was stage 2A. In the prognosis stage I was 1B. The prognosis staging system takes your hormone levels and grade into account and the other staging method does not.
Does this apply if you do chemo before surgery? Will the diagnosis be based on pathology after surgery?
No, it doesn't apply if you have chemo first. You'd do best to ask your doctor how your situation is staged. Between the different TNM and hormonal etc circumstances, it is already confusing for the typical layperson to figure out.
most doctors use the NCCN guidelines for staging breast cancer, which, if we’re talking about IDC, you can find on page 25 of this document: https://www.nccn.org/patients/guidelines/content/PDF/breast-invasive-patient.pdf
(IHC and inflammatory stages usually also use NCCN guidelines, but they are not covered in that document)
don’t let the length of the document intimidate you, it’s written in layman’s terms to help the average reader understand it.
Generally speaking, staging is based on the size of the largest tumor and whether or not it has spread into the lymph nodes (which usually pushes you to stage 2 or 3)or has spread beyond the lymph nodes into the rest of your body (which is almost always stage 4, although there are some weird borderline situations I’ve read about.)
If you have surgery as the first part of your treatment then staging is generally straight forward and the final staging is determined after surgery, although the doctors will also usually have a general guess of the correct stage based on the mammogram and ultrasound imaging and the biopsy results.
If you have chemo first then it’s more complicated and you may never know the true stage. In my case. I was initially staged as 2A because my biggest tumor was 2.8 cm and while one lymph node looked suspicious on ultrasound, the biopsy of the lymph node didn’t show any cancer. I had chemo first because I was HER2 positive. After surgery they determined that the lymph node had reacted to the chemo like there was cancer there, but when I asked if it changed my initial stage from 2A to 2B I basically got a shoulder shrug, because it ultimately didn’t matter that much beyond me obsessing over the small changes in the statistics for my outlook.
Hope that was helpful