The Neo-Bioscore updated breast cancer staging system improves a previously validated staging system (CPS+EG) and allows its application in ERBB2-positive patients receiving neoadjuvant chemotherapy. This according to a study of 2,377 women median age 50 years with ER status <1% in 28.9%, 1% to 9% in 8.3%, and ≥10% in 62.8%. 591 patients were ERBB2-positive and median follow-up was 4.2 years. Researchers found:
• 5-year disease-specific survival was 89%.
• Using 1% or higher as the cutoff for ER positivity, 5-year disease-specific survival estimates determined using the CPS+EG stage ranged from 52% to 98%.
• The AIC value for this model was 3333.06, while for a model using ≥10% as the cutoff for ER positivity, it was 3333.38.
• The improvement in fit of the model when ERBB2 status was added was highly significant, with 5-year disease-specific survival estimates ranging from 48% to 99%.
Citation: Mittendorf EA, Vila J, Tucker SL, et al. The Neo-Bioscore update for staging breast cancer treated with neoadjuvant chemotherapy: Incorporation of prognostic biologic factors into staging after treatment. [Published online ahead of print March 17, 2016]. JAMA Oncol. doi:10.1001/jamaoncol.2015.6478.