In patients with early-stage disease, HER2 is correlated with shorter disease-free survival in breast cancer
These Kaplan-Meier curves show the relationship between HER2 amplification and disease-free survival in node-negative (top) and node-positive (bottom) patients. In both cases, HER2 amplification, defined as having 3 or more copies of the HER2 gene, was significantly correlated with shorter disease-free survival (P=0.009, node-negative patients; P=0.001, node-positive patients).11 Modified with permission from J Clin Oncol vol. 11(10), 1993:1936-1942.
HER2 is a negative prognostic factor
In both breast and ovarian cancers, HER2 is associated with shorter disease-free and overall survival.
In breast cancer
A landmark 1987 study by Slamon et al (N=189) showed a highly statistically significant correlation between HER2 gene amplification and shorter time to disease relapse (P<0.0001) as well as shorter overall survival (P=0.0011)12
In a 1993 study of patients with stage I-III disease (N=1056), 3-fold or greater gene amplification of HER2 was associated with significantly shorter disease-free survival (risk ratio=1.95, P=0.0027)11
HER2 gene amplification was also significantly associated with pathologic stage at diagnosis, axillary node involvement, and histologic subtype
In an additional study of 580 node-negative patients, HER2 overexpression was associated with higher risk of disease recurrence (risk ratio=2.36, P=0.002)13
In ovarian cancer
HER2 positivity levels, as measured by FISH and IHC, have been associated with decreased overall survival in numerous clinical studies14
HER2 positivity levels are also associated with an increase in relative risk of death caused by ovarian cancer14