title: Adjuvant aromatase inhibitor therapy in early breast cancer: what factors lead patients to discontinue treatment?
abstract: BACKGROUND
  Aromatase inhibitors (AIs) are standard hormone therapy (HT) for the adjuvant treatment of postmenopausal endocrine-sensitive early breast cancer. Treatment discontinuation due to toxicity is an important issue that may help clinicians identify effective clinical interventions to allow adequate treatment duration. We reviewed the main reasons for interruption of AIs at our institution from 2006 to 2009.
  
  
  METHODS
  236 patients treated with adjuvant AIs were eligible for analysis. Median age was 64 years (35-89), median follow-up 53 months (6-60). Prior adjuvant chemotherapy was taxane based in 47 patients and anthracycline based in 43 patients. 118 patients had received letrozole, 101 anastrozole, and 17 exemestane.
  
  
  RESULTS
  Twenty-four patients (10%) needed discontinuation of the first AI assigned as a result of toxicity. Grade 2/3 arthralgia was the main reason for discontinuation in 13/24 patients. No differences in the incidence of arthralgia were noted in patients who had received taxanes or anthracyclines. Headache, alopecia, itching, diffuse skin reaction, allergic reaction with hypertensive crisis, xerostomia and xerophthalmia, insomnia and somnolence were the other reasons for discontinuation. In multivariate logistic regression analysis, age (65 years) and HT were independent factors associated with the onset of arthralgia (p = 0.006 and p = 0.008, respectively; OR 2.65, 95% CI 1.32-5.31). Alternative HT (AI or tamoxifen) was offered to patients who wanted or needed to permanently interrupt the ongoing drug.
  
  
  CONCLUSIONS
  In our analysis, 10% of patients discontinued the first AI assigned because of toxicity. Median time course of all adverse events leading to HT discontinuation was 155 days and 135 days for arthralgia. A switch to alternative HT with toxicity monitoring is a recommended option for avoiding premature and permanent interruption of an effective treatment.
authors.affiliation: Oncology Unit and Multidisciplinary Breast Cancer Team, Ospedale Belcolle, AUSL Viterbo, Viterbo - Italy.
authors.forename: Luca
authors.initials: L
authors.lastname: Moscetti
authors.forename: Maria
authors.initials: M
authors.lastname: Agnese Fabbri
authors.forename: Isabella
authors.initials: I
authors.lastname: Sperduti
authors.forename: Nelli
authors.initials: N
authors.lastname: Fabrizio
authors.forename: Patrizia
authors.initials: P
authors.lastname: Frittelli
authors.forename: Annalisa
authors.initials: A
authors.lastname: Massari
authors.forename: Luciano
authors.initials: L
authors.lastname: Pompei
authors.forename: Giuliana
authors.initials: G
authors.lastname: D'Auria
authors.forename: Enrico
authors.initials: E
authors.lastname: Pofi
authors.forename: Enzo Maria
authors.initials: EM
authors.lastname: Ruggeri
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000077384:Anastrozole; D000730:Androstadienes / Q000008:administration & dosage / Q000009:adverse effects; D018931:Antineoplastic Agents, Hormonal / Q000008:administration & dosage* / Q000009:adverse effects*; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D047072:Aromatase Inhibitors / Q000008:administration & dosage* / Q000009:adverse effects*; D018771:Arthralgia / Q000139:chemically induced; D001943:Breast Neoplasms / Q000737:chemistry / Q000188:drug therapy* / Q000473:pathology; D017024:Chemotherapy, Adjuvant; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D000077289:Letrozole; D016015:Logistic Models; D055118:Medication Adherence; D008875:Middle Aged; D060787:Neoplasm Grading; D009367:Neoplasm Staging; D009570:Nitriles / Q000008:administration & dosage / Q000009:adverse effects; D016017:Odds Ratio; D011960:Receptors, Estrogen / Q000032:analysis; D011980:Receptors, Progesterone / Q000032:analysis; D012307:Risk Factors; D014230:Triazoles / Q000008:administration & dosage / Q000009:adverse effects
chemical_list: D000730:Androstadienes; D018931:Antineoplastic Agents, Hormonal; D047072:Aromatase Inhibitors; D009570:Nitriles; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; D014230:Triazoles; D000077384:Anastrozole; D000077289:Letrozole; C056516:exemestane