Wiki Chemo got rid of cancer before surgery?

[marycpc]

I am confused as to how to code this surgery. One of the patients was diagnosed with locally advanced carcinoma left breast and is BRCA positive. So, this patient was instructed to have chemotherapy before the salpingo-oophorectomy and simple mastectomy. The path came back w/patient having no cancer.
Do I use 174.9? or V84.01? or is there another icd code?

Thanks in advance for reading and helping.

Mary