Neoadjuvant treatment before surgery may be recommended, to shrink the tumor before mastectomy or lumpectomy. But neo-adjuvant therapy is usually for node-positive, tumor size over 2 cm, inflammatory or locally advanced HER2+ cancer.

Adjuvant treatment is after surgery and would include Herceptin and Perjeta for one year (18 cycles) along with chemo. There is also a drug called Phesgo that combines Herceptin and Perjeta. The chemo is taken for less time than these drugs. If you look up Phesgo there is a chart comparing the time on chemo and the time on Phesgo.

There is a new drug on trial btw https://www.curetoday.com/view/fda-lifts-hold-on-trial-investigating-novel-drug-in-patients-with-high-risk-breast-cancer

When I was diagnosed with cancer in 2015, Perjeta was new. A lot of advances have taken place in treatment of HER2+. My HER2 tests were confusing. I was told I was HER2+ after biopsy and got an Rx for a wig. Then after surgery it was equivocal at three different labs, and negative with further testing. I had a mixed ductal/lobular tumor. The ductal part of my cancer was positive (the biopsy probably targeted this) and the lobular part was negative, I was told. I still worry whether it should have been treated but I just did hormonal treatment and have made it 7 years.