Broad consensus on the optimal sequence for the systemic treatment of metastatic breast cancer: results from a survey of Spanish medical oncologists

Objective: The aim of this survey conducted by 20 leading Spanish oncologists was to analyze the concurrence between Spanish clinical practice and the recently published definition of the optimal sequence for the systemic treatment of metastatic breast cancer (MBC) according to patient profiles.

Methods: A self-administered questionnaire was developed, divided into 5 sections comprising 34 specific questions related to sequential treatments, plus 3 additional general questions. Respondents were asked to justify negative answers.

Participants were recruited randomly by invitation out of a total of 619 oncologists. The questionnaire was sent and collected via e-mail between October 2015 and May 2016. A total of 191 completed questionnaires were received.

Results: Overall, 70% of oncologists would keep the three patient profiles exactly as proposed (hormone receptor-positive and HER2-negative, HER2-positive, and triple negative breast cancer). Affirmative answers to questions regarding treatment sequences for these patient profiles (1 to 34) ranged from 77.8% to 99.5%, with an average of 90.9% of oncologists being in agreement with the recommended sequential treatments. The lowest degree of consensus was observed for endocrine treatments in pre-menopausal women and for chemotherapy options in hormone-resistant patients, whilst the highest degree of consensus was reached for targeted therapies in HER2-positive patients and for endocrine therapy in post-menopausal women. In their comments, participants revealed a number of economic constraints that prevented them from implementing some of the best treatment options.

Conclusions: In conclusion, despite the complexity of MBC treatment, there is general agreement on the optimal treatment sequences.