title: Adherence and persistence with oral adjuvant chemotherapy in older women with early-stage breast cancer in CALGB 49907: adherence companion study 60104.
abstract: OBJECTIVE
  Patient adherence is critical in evaluating the effectiveness of an oral therapy. We sought to measure adherence among women randomly assigned to capecitabine in a preplanned substudy of a multicenter clinical trial.
  
  
  METHODS
  Cancer and Leukemia Group B study CALGB 49907 was a randomly assigned trial comparing standard chemotherapy versus oral chemotherapy with capecitabine in patients age 65 years or older with early-stage breast cancer. We used microelectronic monitoring system (MEMS) caps on participants' capecitabine bottles to record pill bottle openings. Capecitabine was given in two divided daily doses for 14 consecutive days of a 21-day cycle for six cycles. Adherence was calculated as the number of doses taken divided by doses expected, taking into account toxicity-related dosing changes. A participant was defined as adherent if 80% or more of expected doses were recorded by MEMS.
  
  
  RESULTS
  Overall, 161 patients were enrolled. Median age was 71 years (range, 65 to 89 years); 124 patients (83%) persisted with capecitabine to completion of planned protocol therapy. Adherence was 78% across all cycles, and adherence did not vary by cycle (P = .32). Twenty-five percent of participants took fewer than 80% of expected doses and were nonadherent. In a logistic regression model, participants with node-negative disease (P = .01) and mastectomy (P = .01) were more likely to be nonadherent. Adherence was not related to age, tumor stage, or hormone receptor status. Adherence was not significantly associated with relapse-free survival or grade 3 or 4 toxicity.
  
  
  CONCLUSIONS
  Most older women with early-stage breast cancer were adherent to short-term oral chemotherapy in a randomized clinical trial. Age was not associated with adherence.
authors.affiliation: Dana-Farber Cancer Institute, 44 Binney St, Boston, MA 02115, USA. ahpartridge@partners.org
authors.forename: Ann H
authors.initials: AH
authors.lastname: Partridge
authors.forename: Laura
authors.initials: L
authors.lastname: Archer
authors.forename: Alice B
authors.initials: AB
authors.lastname: Kornblith
authors.forename: Julie
authors.initials: J
authors.lastname: Gralow
authors.forename: Debjani
authors.initials: D
authors.lastname: Grenier
authors.forename: Edith
authors.initials: E
authors.lastname: Perez
authors.forename: Antonio C
authors.initials: AC
authors.lastname: Wolff
authors.forename: Xiaofei
authors.initials: X
authors.lastname: Wang
authors.forename: Helen
authors.initials: H
authors.lastname: Kastrissios
authors.forename: Donald
authors.initials: D
authors.lastname: Berry
authors.forename: Clifford
authors.initials: C
authors.lastname: Hudis
authors.forename: Eric
authors.initials: E
authors.lastname: Winer
authors.forename: Hyman
authors.initials: H
authors.lastname: Muss
mesh_terms: D000284:Administration, Oral; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000964:Antimetabolites, Antineoplastic / Q000008:administration & dosage* / Q000009:adverse effects; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D002170:Canada; D000069287:Capecitabine; D017024:Chemotherapy, Adjuvant; D003841:Deoxycytidine / Q000008:administration & dosage / Q000009:adverse effects / Q000031:analogs & derivatives*; D004334:Drug Administration Schedule; D016903:Drug Monitoring / Q000295:instrumentation; D005260:Female; D005472:Fluorouracil / Q000008:administration & dosage / Q000009:adverse effects / Q000031:analogs & derivatives*; D006801:Humans; D053208:Kaplan-Meier Estimate; D016014:Linear Models; D016015:Logistic Models; D008408:Mastectomy; D055118:Medication Adherence; D055617:Micro-Electrical-Mechanical Systems / Q000295:instrumentation; D009367:Neoplasm Staging; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome; D014481:United States
chemical_list: D000964:Antimetabolites, Antineoplastic; D003841:Deoxycytidine; D000069287:Capecitabine; D005472:Fluorouracil