Is a breast MRI possible and indicated in case of suspicion of breast cancer during lactation?

Breast MRI during pregnancy and lactation: clinical challenges and technical advances

The breast experiences substantial changes in morphology and function during pregnancy and lactation which affects its imaging properties and may reduce the visibility of a concurrent pathological process. The high incidence of benign gestational-related entities may further add complexity to the clinical and radiological evaluation of the breast during the period. Consequently, pregnancy-associated breast cancer (PABC) is often a delayed diagnosis and carries a poor prognosis. This state-of-the-art pictorial review illustrates how despite currently being underutilized, technical advances and new clinical evidence support the use of unenhanced breast MRI during pregnancy and both unenhanced and dynamic-contrast enhanced (DCE) during lactation, to serve as effective supplementary modalities in the diagnostic work-up of PABC.

MRI Evaluation of the Lactating Breast

Purpose of Review

To review the MRI appearance of physiologic lactational changes, common benign pathologies, and malignancies in the lactating breast.

Recent Findings

The prevalence of pregnancy-associated breast cancer has increased as more women delay childbirth and lactation. There is a transient increase in breast cancer risk after delivery when women may be lactating. MRI is more sensitive than mammography and ultrasound for the evaluation of the extent of disease in lactating women.

Summary

Understanding the key MRI findings of benign and malignant pathologies in the lactating breast is critical for accurate diagnosis and prompt evaluation of pregnancy-associated breast cancer.

Breast imaging screening in a BRCA1-mutated lactating patient: A potential pitfall mimicking malignancy

Breast imaging screening during lactation poses a real clinical challenge, especially in high-risk patients. We presented the case of a 34-year-old BRCA1-mutated woman showing marked, asymmetric background parenchymal enhancement on the right breast suspicious for malignancy in the context of annual screening magnetic resonance imaging. The patient revealed that she was still occasionally breastfeeding her two-year-old child only from right side. Ultrasound evaluation reported typical benign lactational findings on the right enhancing breast. An in-depth understanding of expected/ physiologic breast changes during lactation and an accurate clinical-radiological correlation are required to appropriately guide patient management and avoid misdiagnosis.

Surgical Risk Reduction, Breast Cancer and Childbearing

Purpose of Review

Young women who carry a genetic predisposition to breast cancer need to balance surgical and nonsurgical risk reducing options with childbearing. In this review, we explore how women make decisions without the benefit of official guidelines and in the context of frequently contradictory strategies.

Recent Findings

Women of reproductive age with known BRCA mutations receive incomplete and conflicting advice regarding the urgency and timing of risk reducing mastectomy (RRM). Those who prioritize RRM achieve highly effective prevention and thereby avoid not only a diagnosis of breast cancer but also adjuvant therapies which limit future childbearing. All reconstructive options are available and high levels of satisfaction are reported. Those who delay prophylactic mastectomy can pursue nonsurgical breast and ovarian risk reduction strategies such as tamoxifen and oral contraception, yet these delay child bearing. Women who prioritize child bearing maintain the ability to breast feed but have limited screening options during pregnancy and lactation.

Summary

Prioritization and timing of risk reduction and childbearing in young BRCA positive women is challenging. Elucidating these challenges enables clinicians to better counsel these women.

Current Recommendations for Breast Imaging of the Pregnant and Lactating Patient

During pregnancy and lactation, the breast undergoes unique changes that manifest as varied clinical and imaging findings. Understanding the expected physiologic changes of the breast as well as recognizing the best imaging modalities for a given clinical scenario can help the radiologist identify the abnormalities arising during this time. Discussion with the patient about the safety of breast imaging can reassure patients and improve management. This article reviews the physiologic changes of the breast during pregnancy and lactation; the safety and utility of various imaging modalities; upto-date consensus on screening guidelines; recommendations for diagnostic evaluation of breast pain, palpable abnormalities, and nipple discharge; and recommendations regarding advanced modalities such as breast MRI. In addition, the commonly encountered benign and malignant entities affecting these patients are discussed.

ABM Clinical Protocol #30: Radiology and Nuclear Medicine Studies in Lactating Women

A central goal of the Academy of Breastfeeding Medicine is the development of clinical protocols for managing common medical problems that may impact breastfeeding success. These protocols serve only as guidelines for the care of breastfeeding mothers and infants and do not delineate an exclusive course of treatment or serve as standards of medical care. Variations in treatment may be appropriate according to the needs of an individual patient.

Breast Ultrasound during Lactation: Benign and Malignant Lesions

Background

Structural changes during lactation make breast physical examination difficult. When breast problems occur, patients are often referred for an ultrasound (US) scan. Most breast lesions diagnosed in these patients are benign, but the diagnosis of breast cancer is a challenge. We aim to demonstrate the spectrum of US imaging findings in lactating women.

Methods

77 breastfeeding patients who underwent breast US in our department between February 2012 and March 2017 were evaluated. Patients' electronic medical records were reviewed for the presenting complaint, US reports, pathology results if available, and clinical/radiologic follow-up. All examinations were performed by 2 radiologists.

Results

28 of the 77 patients had normal US findings. Cysts were seen in 16 patients. 4 patients had stable fibroadenomas. 6 patients had US imaging findings suggestive of mastitis, 5 patients had galactoceles, 1 patient had an abscess, and 1 patient had unilateral hypertrophy without any accompanying lesion. In 13 patients, BI-RADS 3 solid masses were diagnosed. Invasive breast cancer was diagnosed in 3 patients.

Conclusion

US can demonstrate or exclude a true mass against the background of a nodular breast parenchyma. Radiologists must be aware of malignant US features to avoid delays in the diagnosis of pregnancy-associated breast cancer.

ACR Appropriateness Criteria® Breast Imaging of Pregnant and Lactating Women

Breast imaging during pregnancy and lactation is challenging due to unique physiologic and structural breast changes that increase the difficulty of clinical and radiological evaluation. Pregnancy-associated breast cancer (PABC) is increasing as more women delay child bearing into the fourth decade of life, and imaging of clinical symptoms should not be delayed. PABC may present as a palpable lump, nipple discharge, diffuse breast enlargement, focal pain, or milk rejection. Breast imaging during lactation is very similar to breast imaging in women who are not breast feeding. However, breast imaging during pregnancy is modified to balance both maternal and fetal well-being; and there is a limited role for advanced breast imaging techniques in pregnant women. Mammography is safe during pregnancy and breast cancer screening should be tailored to patient age and breast cancer risk. Diagnostic breast imaging during pregnancy should be obtained to evaluate clinical symptoms and for loco-regional staging of newly diagnosed PABC. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Monitoring In-Vivo the Mammary Gland Microstructure during Morphogenesis from Lactation to Post-Weaning Using Diffusion Tensor MRI

Lactation and the return to the pre-conception state during post-weaning are regulated by hormonal induced processes that modify the microstructure of the mammary gland, leading to changes in the features of the ductal / glandular tissue, the stroma and the fat tissue. These changes create a challenge in the radiological workup of breast disorder during lactation and early post-weaning. Here we present non-invasive MRI protocols designed to record in vivo high spatial resolution, T₂-weighted images and diffusion tensor images of the entire mammary gland. Advanced imaging processing tools enabled tracking the changes in the anatomical and microstructural features of the mammary gland from the time of lactation to post-weaning. Specifically, by using diffusion tensor imaging (DTI) it was possible to quantitatively distinguish between the ductal / glandular tissue distention during lactation and the post-weaning involution. The application of the T₂-weighted imaging and DTI is completely safe, non-invasive and uses intrinsic contrast based on differences in transverse relaxation rates and water diffusion rates in various directions, respectively. This study provides a basis for further in-vivo monitoring of changes during the mammary developmental stages, as well as identifying changes due to malignant transformation in patients with pregnancy associated breast cancer (PABC).