In which patients will you consider a shorter course of adjuvant Herceptin?

At this point, I would not treat any patients with short term trastuzumab. The Short-Her study had very wide confidence intervals for non-inferiority, and there was a numerically superior 2.2% improvement in DFS in the long (standard) trastuzumab arm. Additionally, in the patients with the worst prognosis (1-3 and 4+ nodes), the standard length trastuzumab was superior. There are still benefits to standard term T--we can debate the precise benefit, but this benefit exists in every category of Her2 positive early stage breast cancer.

I agree with @Dr. First Last. Notably, the FinHer adjuvant chemo+/- trastuzumab study evaluated the impact of chemotherapy with or without only 9 weeks of trastuzumab and demonstrated hazard ratios similar to those reported in other studies. However, one year of trastuzumab has remained the standard for many of the reasons that @Dr. First Last stated. That being said, when issue arise that preclude completion of one year (i.e. asymptomatic significant declines in LVEF without opportunity to rechallenge), it is reassuring to have growing data that shorter courses are effective.

Ref: Joensuu H, Bono P, Kataja V, Alanko T, Kokko R, Asola R, . Fluorouracil, epirubicin, and cyclophosphamide with either docetaxel or vinorelbine, with or without tr...