Significant vascular and stromal remodeling is necessary to support the expanded epithelium of pregnancy and lactation, and these changes in the breast microenvironment could potentially be leveraged by breast cancer cells, leading to an increase in biologic aggressiveness [2,18,20]. Despite the long-term decreased risk of breast cancer with pregnancy, there are some data to suggest that there may be a transient increased risk for breast cancer during pregnancy and lactation [6]. Some studies show that women with BRCA gene mutations are overrepresented in PABC, and pregnant and lactating women are more likely to have hormone-negative breast cancer than age-matched controls [7,18,21,22]. Although the underlying cause for these observations is not clear, they support the possibility that the tumor biology of PABC is more aggressive than non-PABC breast cancer in young women with equivalent stage and prognostic factors. The most common presentation of PABC is a palpable mass. Therefore, imaging evaluation of a palpable lesion in a pregnant or lactating woman should not be delayed [7,20,23,24]. Less common presenting complaints include focal pain, diffuse breast enlargement, nipple discharge, and, rarely, unilateral milk rejection in which the infant rejects milk from the breast harboring cancer [7,24]. The imaging appearance of PABC is similar to breast cancer in nonpregnant patients. Because of the young age of these women and higher likelihood of triple negative breast cancer, PABC is more likely to demonstrate areas of necrosis[13,25]. In addition, PABC may have a falsely benign appearance presenting as a mass with relatively circumscribed margins, parallel orientation, and posterior acoustic enhancement [1,7]. aDartmouth-Hitchcock Medical Center, Lebanon, New Hampshire. bBeth Israel Deaconess Medical Center, Boston, Massachusetts. cPanel Vice-Chair, NYU Clinical Cancer Center, New York, New York.
Breast Imaging of Pregnant and Lactating Women. Significant vascular and stromal remodeling is necessary to support the expanded epithelium of pregnancy and lactation, and these changes in the breast microenvironment could potentially be leveraged by breast cancer cells, leading to an increase in biologic aggressiveness [2,18,20]. Despite the long-term decreased risk of breast cancer with pregnancy, there are some data to suggest that there may be a transient increased risk for breast cancer during pregnancy and lactation [6]. Some studies show that women with BRCA gene mutations are overrepresented in PABC, and pregnant and lactating women are more likely to have hormone-negative breast cancer than age-matched controls [7,18,21,22]. Although the underlying cause for these observations is not clear, they support the possibility that the tumor biology of PABC is more aggressive than non-PABC breast cancer in young women with equivalent stage and prognostic factors. The most common presentation of PABC is a palpable mass. Therefore, imaging evaluation of a palpable lesion in a pregnant or lactating woman should not be delayed [7,20,23,24]. Less common presenting complaints include focal pain, diffuse breast enlargement, nipple discharge, and, rarely, unilateral milk rejection in which the infant rejects milk from the breast harboring cancer [7,24]. The imaging appearance of PABC is similar to breast cancer in nonpregnant patients. Because of the young age of these women and higher likelihood of triple negative breast cancer, PABC is more likely to demonstrate areas of necrosis[13,25]. In addition, PABC may have a falsely benign appearance presenting as a mass with relatively circumscribed margins, parallel orientation, and posterior acoustic enhancement [1,7]. aDartmouth-Hitchcock Medical Center, Lebanon, New Hampshire. bBeth Israel Deaconess Medical Center, Boston, Massachusetts. cPanel Vice-Chair, NYU Clinical Cancer Center, New York, New York.