The 70-Gene Signature as Prognostic Factor for Elderly Women with Hormone Receptor-Positive, HER2-Negative Breast Cancer

Background: The aim of this article was to evaluate the prognostic value of the MammaPrint (TM) signature in women >= 60 years with invasive breast cancer. Patients and Methods: 60 female patients were included in this prospective study. Eligibility criteria included: pT1c-3, pN0-1a, grade 2/3, hormone receptor-positive and HER2-negative tumor. The clinical risk was determined by Adjuvant! Online (AOL). Results: 38 patients (63%) where considered to be low-risk patients by the 70-gene signature, while 22 (37%) were considered to be high-risk patients. No statistically significant differences between low- and high-risk groups could be detected for conventional prognostic parameters, particularly not for Ki-67. By AOL, 33 patients (55%) were considered to be at high risk, of which 20 had a discordant MammaPrint (TM) result. The discordance rate between the profile and AOL was 48%, which is higher than in previous publications. When the 70-gene signature was used in combination with the clinical risk assessment, the recommendation for adjuvant systemic treatment differed in 11 patients (18%). Conclusions: In the intermediate-risk subgroup, the 70-gene signature could be useful to decide in elderly patients whether they may benefit from adjuvant chemotherapy or not. Conventional clinicopathological factors were not suitable for a prediction of the 70-gene signature results in these patients.