title: Intermediate endpoints of primary systemic therapy in breast cancer patients.
abstract: Primary systemic therapy (PST) in breast cancer offers the opportunity to explore interactions between tumor biology and administered treatment. Changes in clinical, tissue-based, or imaging markers can provide information on the mechanisms of PST activity (activity endpoints) or predict treatment efficacy (surrogate endpoints). The most frequently used intermediate endpoint for PST is pathological complete response, but its role as a surrogate parameter of efficacy has not yet been demonstrated. Changes in tumor biology after PST may occur already a few days after treatment start; this implies that new potential surrogates occurring much earlier than pathological complete response (ie, the proliferation marker Ki67) can be identified and that short-term preoperative trials (window-of-opportunity trials) can be designed using a biological parameter as a primary endpoint. From these small trials, crucial information can be gleaned about the activity of new drugs for the design of large clinical trials.
authors: Oncologia Medica, Azienda Ospedaliero Universitaria San Luigi, 10043 Orbassano, Italy. alfredo.berruti@gmail.com
authors: Alfredo
authors: A
authors: Berruti
authors: Daniele
authors: D
authors: Generali
authors: Valentina
authors: V
authors: Bertaglia
authors: Maria Pia
authors: MP
authors: Brizzi
authors: Teresa
authors: T
authors: Mele
authors: Luigi
authors: L
authors: Dogliotti
authors: Paolo
authors: P
authors: Bruzzi
authors: Alberto
authors: A
authors: Bottini
mesh_terms: D018931:Antineoplastic Agents, Hormonal / Q000627:therapeutic use; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D014408:Biomarkers, Tumor / Q000378:metabolism*; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology*; D005260:Female; D006801:Humans; D019394:Ki-67 Antigen / Q000378:metabolism; D009367:Neoplasm Staging; D016896:Treatment Outcome
chemical_list: D018931:Antineoplastic Agents, Hormonal; D014408:Biomarkers, Tumor; D019394:Ki-67 Antigen