Breast Cancer Awareness Month: Postpartum Breast CancerOct 14, 2021
| Breast cancer is the second-most common cancer diagnosis in women, affecting more than 260,000 women in the U.S. every year and according to the National Cancer Institute 25,000 of women diagnosed are younger than the age of 45. A 2019 study by Dr. Virginia Borges and her colleagues at the University of Colorado and Oregon Health and Science University shows that breast cancers diagnosed in young women within ten years of giving birth are more likely to metastasize than breast cancers in young women who gave birth less recently or not at all. According to Dr. Borges, this study was the first of its kind to demonstrate that a postpartum breast cancer diagnosed up to ten years after last childbirth can independently increase a woman’s risk for developing metastasis to other parts of the body.
The increased risk for metastasis was highest in the women up to ten years postpartum and was most pronounced in women with stage I or II breast cancer, with a risk 3.5 to 5 times higher than women with similar, non-pregnancy associated cancers. Estrogen-receptor positive tumors presented an increased risk of metastasis up to 15 years post-diagnosis, approaching the level of metastasis risk associated with dangerous forms of breast cancer including ER-negative and triple-negative breast cancers.
"These data support previous findings from our team’s lab work showing that after childbirth, conditions in surrounding breast tissue may aid the development of metastases. For example, we have shown that the laying down of new lymph channels in breast tissue after childbirth and nursing may allow cancer cells to better travel and seed sites of metastasis; sure enough, the current work finds more women having cancer in their lymph nodes at diagnosis" says Dr. Borges.
The findings from this study are critical in highlighting the importance of understanding that postpartum breast cancer represents a unique subtype of cancer that requires distinct care. Awareness of increased risk will allow clinicians and researchers to work towards finding the best means of appropriate treatment.
The continuous improvement of breast cancer survival rates, with five year survival rates over 90%, can in large part be attributed to regular screenings. Early-stage cancer is much easier to treat than later-stage cancers, many of which can spread to other parts of the body.