is it possible her2 negative to her2 positive breast cancer in five year

[Deepak1965]

Hello Doctor, my wife diagnosed with breast cancer in july 2015 was oligo metastatic in IHC er 95% + pr negative and her2 neu also negative we gave her 4 cycle 5FEC chemo than done pet scan shows partial response to chemo metabolic activity reduce 75% to 19% we took second opinion at TATA hospital and they ask us to do one cycle of doce taxel chemo we done it but it was very harsh with 4stage toxicity on body so stopped and done the BCS surgery removed lump and 9 nodes in ihs nodes were negative for cancer cells than 2 chemo given again of 5FEC and than till jan-2021 she was on tamoxifen 20 MG in 2018 last pet scan it show total cancer free no metabolic activity in body. in JAN-2021 she felt lump in same operated bed we done pet scan shows that cancer cells shows in 5 place left breast right auxiliary,mediastinal, iliac bone and right lobe of liver that means its stage 4 . than we do biopsy earlier her2 was negative this time her2 got positive. what should we do and how long is life span for this type of patients doctor says only letrozole 2.5 mg tab no chemo what should we do

[trpl]

Hello Mr Deepak , I am on Letrozole 2.5 mg for the past 5 years. In 2015 diagnosed with IDC 2A , tumour size 2cm, 1 out of 15 lymph nodes positive . Underwent BCS , 4 AC 4 Paclitaxel, Radiation, since it was HER -veER PR +ve , Bilateral Oopherectomy. In last December during regular follow up Dr advised to continue Letrozole for another 5 years as per new recommendation. How did your wife end up with stage 4 ?Did you have regular follow up with your Dr? Hope in Almighty for good