title: Use of Cox's Cure Model to Establish Clinical Determinants of Long-Term Disease-Free Survival in Neoadjuvant-Chemotherapy-Treated Breast Cancer Patients without Pathologic Complete Response.
abstract: In prognostic studies for breast cancer patients treated with neoadjuvant chemotherapy (NAC), the ordinary Cox proportional-hazards (PH) model has been often used to identify prognostic factors for disease-free survival (DFS). This model assumes that all patients eventually experience relapse or death. However, a subset of NAC-treated breast cancer patients never experience these events during long-term follow-up (>10 years) and may be considered clinically "cured." Clinical factors associated with cure have not been studied adequately. Because the ordinary Cox PH model cannot be used to identify such clinical factors, we used the Cox PH cure model, a recently developed statistical method. This model includes both a logistic regression component for the cure rate and a Cox regression component for the hazard for uncured patients. The purpose of this study was to identify the clinical factors associated with cure and the variables associated with the time to recurrence or death in NAC-treated breast cancer patients without a pathologic complete response, by using the Cox PH cure model. We found that hormone receptor status, clinical response, human epidermal growth factor receptor 2 status, histological grade, and the number of lymph node metastases were associated with cure.
authors.affiliation: Department of Management Science, Tokyo University of Science, Shinjuku-ku, Tokyo 162-8601, Japan.
authors.forename: Junichi
authors.initials: J
authors.lastname: Asano
authors.affiliation: Center for Advanced Medicine and Clinical Research, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8560, Japan.
authors.forename: Akihiro
authors.initials: A
authors.lastname: Hirakawa
authors.affiliation: Department of Management Science, Tokyo University of Science, Shinjuku-ku, Tokyo 162-8601, Japan.
authors.forename: Chikuma
authors.initials: C
authors.lastname: Hamada
authors.affiliation: Department of Breast and Medical Oncology, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045, Japan.
authors.forename: Kan
authors.initials: K
authors.lastname: Yonemori
authors.affiliation: Department of Respiratory Medicine, Okayama University Hospital, 2-5-1 Shikata-cho, Okayama 700-8558, Japan.
authors.forename: Taizo
authors.initials: T
authors.lastname: Hirata
authors.affiliation: Department of Breast and Medical Oncology, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045, Japan.
authors.forename: Chikako
authors.initials: C
authors.lastname: Shimizu
authors.affiliation: Department of Breast and Medical Oncology, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Tamura
authors.affiliation: Department of Breast and Medical Oncology, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045, Japan.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Fujiwara