Patients' preference for administration of endocrine treatments by injection or tablets: results from a study of women with breast cancer.

Endocrine therapies for advanced breast cancer include tablets and intramuscular injections. When treatments have similar efficacy and tolerability profiles, addressing preferences about routes of administration is important. Two hundred and eight women>2 years post-breast cancer diagnosis were interviewed about their preferences for daily tablets or monthly intramuscular injections. Health-care professionals treating the women estimated patients' preferences. Sixty-three per cent of patients preferred tablets, 24.5% preferred the injection and 12.5% had no preference. The most cited reasons for tablet preference were convenience and dislike of needles; for injection preference, adherence and convenience. Variables associated with preferences were body mass index, educational level, attitudes towards injections and efficacy perceptions. Estimates about patients' preferences by health-care professionals varied widely. When asked to imagine scenarios where injections produced fewer hot flushes, or where two injections monthly improved efficacy, injection preference increased to 60.6% and 74.5%, respectively. Disturbingly, approximately 50% of patients admitted they sometimes forgot or chose not to take their current oral medication. The majority of breast cancer patients preferred hormone therapy via daily tablets rather than monthly injections. Information about side-effects or improved efficacy altered these preferences. Adherence to treatment cannot be assumed; patients' preferences about drug administration may influence this.