Current Management Practices of De Novo Oligometastatic Breast Cancer: Real-World Data From a Physician Survey.

Abstract

Oligometastatic breast cancer (oligo-mBC) represents up to 40% of newly diagnosed metastatic breast cancers. The current standard of care in the United States is to treat metastatic breast cancer palliatively although optimal management of de novo oligo-mBC remains uncertain and practice patterns in the treatment of oligo-mBC vary. We present a survey of US medical oncologists regarding their management of de novo oligo-mBC. All ASCO members who participate in the ASCO Survey Pool (999) were sent an invitation e-mail between November 14, 2023, and January 2, 2024. The survey asked eight demographic questions, and four questions focused on treatment preferences, per receptor subtype-estrogen receptor-positive, human epidermal growth factor receptor 2-positive (HER2+), and triple-negative disease. A total of 144 of 193 respondents met the criteria of medical oncologists who treat breast cancer. A total of 136 medical oncologists who treat breast cancer completed the survey. The majority of respondents recommend initial palliative systemic chemotherapy; however, if a patient shows a positive response to initial chemotherapy, a substantial amount of respondents (42%-54%) recommend ablative radiation of all residual lesions and 38%-52% recommend surgical resection of the primary tumor. The results varied by receptor subtype, with the highest percentage of respondents recommending curative-intent therapies in HER2+ disease, although these differences were not statistically significant. Our results indicate varied practice patterns in the treatment of de novo oligo-mBC. A substantial number of medical oncologists recommend ablative radiation and surgical resection of the primary breast tumor. This highlights the need for clarity regarding practice guidelines in de novo oligo-mBC.