cerb2=+3 score prognosis and treatment plan

i am a dentist, my mother  age 46yrs recently undergone mastectomy  FNAC report showd infiltrating duct carcinoma size was 3x3x3 approx and histopath report says 2 out of 7 lymphnode metastasis and NOS grade III .
ER n PR are  postive in intraductal component only, but cerb2 shows score3 positive
what is the prognosis  and from where can i get herceptin injecton at lower cost