Virginia Borges, MD

Improving outcomes for women with postpartum breast cancer.

Impact

Postpartum breast cancer (PPBC) is diagnosed within 5-10 years of childbirth. Rates of PPBC are rising as women delay childbearing, and it is associated with higher risk for metastasis and death compared to breast cancer in younger women before or during pregnancy. Prior research has identified biological events such as breast tissue remodeling that occurs after lactation or pregnancy without nursing as inciting events that promote aggressive breast cancer. Biological mechanisms such as a change in normal proteins that regulate signaling in the breast, new lymphatic vessels forming from pre-existing ones, an increase in inflammation, and the expression of a gene called SEMA7A have also been found to contribute to poorer outcomes. With early-onset breast cancer (EOBC) cases projected to reach 50,000 annually in the U.S. by 2050, and PPBC expected to make up roughly half of those cases, understanding and targeting these mechanisms is an urgent priority. Dr. Borges seeks to understand the biology of PPBC and improve outcomes for this population.

Progress Thus Far

Dr. Borges and her team have made progress expanding their work on EOBC and pregnancy-associated breast cancer (PPBC), including expanding their Colorado cohort to include Latina women. Using data from the long-running I-SPY clinical trial, they have identified genomic features that may be important to the aggressiveness of PPBC tumors. In addition, the team is helping to build one of the largest, most detailed cohorts of EOBC and PPBC patients through the Oncology Research and Information Exchange Network (ORIEN), linking clinical, genetic, and long-term outcome data across a consortium of 19 cancer centers. To support this effort, Dr. Borges established a new Breast Cancer Research Interest Group that has compiled data on more than 700 young women with breast cancer ready for analysis.
A major advance this year has been the team’s work on extracellular vesicles (EVs), tiny, cargo-carrying structures that tumors release into the bloodstream as messengers. The team found that SEMA7A is present in these EVs, and that their protein content lines up with signs of systemic immune suppression, suggesting EVs may play a direct role in driving treatment resistance and metastasis in PPBC. In parallel, the team has expanded its work to collect data on social determinants of health and is now investigating whether a woman’s microbiome may influence her risk of developing PPBC or her outcomes once diagnosed.

What’s next

In the upcoming year, Dr. Borges’ The team will work across multiple patient cohorts to identify and validate biomarkers for PPBC, correlating findings with treatment resistance, commercial genomic tests, and novel AI-based tools, as well as the social determinants of health and microbiome data now being collected. The team plans to expand the PPBC database, to potentially include data from over 4,000 women diagnosed under age 45. This data set will provide the strongest potential to study PPBC and validate predictive factors for PPBC outcomes and, importantly, include PPBC cases across races, geographical locations, and up to age 45, as women are electing to delay childbearing and are diagnosed in their early 40s. The goal is to define new therapeutic targets that can support PPBC-specific clinical trials, establish treatment guidelines tailored to this subtype, and sharpen risk profiles for who is most likely to develop PPBC or experience poor outcomes.