Differing Guidelines, Case-by-Case Considerations
The RadioGraphics paper emphasizes that both screening and diagnostic imaging can be safely performed using protocols based on age, breast cancer risk, and whether the patient is pregnant or lactating.
The American College of Radiology (ACR) Appropriateness Criteria also support mammography for certain patients during lactation. The guidelines state there is no contraindication to performing mammography during lactation, but note that challenges in evaluation can arise because of the unique physiological and structural breast changes that can occur.
“Hormones can change breast density and size of the breast, which could limit the clinical examination, mimic pathology, and obscure mammographic findings,” said Stamatia V. Destounis, MD, FACR, chair of the ACR Breast Imaging Commission. “It is important the patient pumps right before the mammogram or brings the baby to breastfeed prior to the imaging examination to offer the best imaging evaluation and reduce breast density as much as possible.”
In those patients who choose to prolong breastfeeding and are of the age to be screened, it is important they undergo yearly clinical breast exams, perform breast self-exams, and discuss breast cancer screening with their healthcare provider, she said. “They should not delay a routine screening mammogram. Most patients have dense breast tissue at this time, and frequently a breast ultrasound may be performed also.”
The American College of Obstetricians and Gynecologists (ACOG) does not have specific guidelines about breastfeeding mothers and mammography recommendations. Breastfeeding patients should discuss with their physicians or midwives the pros and cons of mammography, taking into account personal risk factors and how long they plan to nurse, said Joshua Copel, MD, vice chair of obstetrics, gynecology and reproductive sciences at Yale Medicine, New Haven, Connecticut, and a member of ACOG’s Committee on Obstetric Practice.
“The question for anybody to address with their physician will be, ‘Is my risk of breast cancer high enough that I should take that small risk that they’re going to over- or underread the mammogram because of my nursing status? Or should I wait until I wean the baby and have the mammogram then?’” he said.
Institutional and practice protocols meanwhile, can depend on a patient’s cancer risk.
Guidelines at the University of Wisconsin, for instance, advise that lactating patients 40 or over who are at average risk, wait 6-8 weeks after cessation of breastfeeding, said Alison Gegios, MD, a radiologist and assistant professor in breast imaging at the University of Wisconsin School of Medicine and Public Health. Average risk is defined as less than a 15% lifetime risk of breast cancer, she said.
Dr. Gegios, a coauthor on the RadioGraphics paper, said her institution recommends screening mammography if lactating patients are at intermediate or high risk, and are over 30. In such cases however, screening is generally deferred until 3-6 months after delivery, she noted.
“If patients are high risk, it’s also important to do screening breast MRIs,” Dr. Gegios said. “Studies have shown that screening breast MRIs are effective in breastfeeding patients despite their increased background parenchymal enhancement because breast cancer still stands out on our maximum intensity projections and stands out on the exam from the background.”