The 70-gene signature (MammaPrintTM) is a prognostic tool used to guide adjuvant treatment decisions. The aim of this study was to assess its value to predict chemosensitivity in the neoadjuvant setting. We obtained the 70-gene proﬁle of stage II–III patients prior to neoadjuvant chemotherapy and classiﬁed the prognosis- signatures. Pathological complete remission (pCR) was used to measure chemosensitivity. Among 167 patients, 144 (86%) were having a poor and 23 (14%) a good prognosis-signature. None of the good prognosis-signature patients achieved a pCR (0/23), whereas 29/144 patients (20%) in the poor prognosis-signature group did (P = 0.015). All triple-negative tumors (n = 38) had a poor prognosis-signature. Within the non triple-negative sub- group, the response of the primary tumor remained associated with the classiﬁcation of the prognosis-signature (P = 0.023). A pCR is unlikely to be achieved in tumors that have a good prognosis-signature. Tumors with a poor prognosis-signature are more sensitive to chemotherapy. See article.
Publication Name: Breast Cancer Research and Treatment