Screening and Diagnostic Mammography During Pregnancy and Lactation: A Systematic Review of the Literature

In recent years, the age of childbearing has been increasing in Western countries, and consequently the need to conduct mammography during pregnancy and lactation is also increasing. The aim of the present study was to systematically review the existing evidence regarding the overall use of mammography during pregnancy and lactation. A systematic review of the literature was conducted in PubMed, Epistemonikos, and clinicaltrials.gov, by using the search terms "pregnancy" AND "mammography", and "lactation" AND "mammography". The review protocol was prospectively registered in PROSPERO (CRD42024543971). Initially, 1,038 articles were identified; the titles and abstracts of 441 studies were screened; 40 studies were retrieved; after assessment of full texts, 20 studies were included for data extraction and further analysis. All 20 studies were retrospective; 14 studies included women with pregnancy-associated breast cancer, five studies included women with breast symptoms during pregnancy and/or lactation and one study included young breast cancer patients under age 40. Overall, 420 diagnostic and one incidental screening mammography examinations were performed during pregnancy and/or lactation with a 78.6% cumulative detection rate of breast cancer. The role of mammography was confounded by the use of breast ultrasound in most studies. In conclusion, the use of mammography during pregnancy and lactation is based on empirical data from retrospective studies, not directly addressing this issue. Hence, well-designed, focused, prospective clinical studies are needed in order to improve existing evidence regarding the use of diagnostic and screening mammography during pregnancy and lactation.

MRI of the Lactating Breast

The breasts undergo marked physiologic changes during lactation that can make conventional imaging evaluation with mammography and US challenging. MRI can be a valuable diagnostic aid to differentiate physiologic and benign processes from malignancy in patients who are lactating. In addition, MRI may allow more accurate delineation of disease involvement than does conventional imaging and assists in locoregional staging, screening of the contralateral breast, assessment of response to neoadjuvant chemotherapy, and surgical planning. Although the American College of Radiology recommends against patients undergoing contrast-enhanced MRI during pregnancy because of fetal safety concerns, contrast-enhanced MRI is safe during lactation. As more women delay childbearing, the incidence of pregnancy-associated breast cancer (PABC) and breast cancer in lactating women beyond the 1st year after pregnancy is increasing. Thus, MRI is increasingly being performed in lactating women for diagnostic evaluation and screening of patients at high risk. PABC is associated with a worse prognosis than that of non-PABCs, with delays in diagnosis contributing to an increased likelihood of advanced-stage disease at diagnosis. Familiarity with the MRI features of the lactating breast and the appearance of various pathologic conditions is essential to avoid diagnostic pitfalls and prevent delays in cancer diagnosis and treatment. The authors review clinical indications for breast MRI during lactation, describe characteristic features of the lactating breast at MRI, and compare MRI features of a spectrum of benign and malignant breast abnormalities. ©RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material. See the invited commentary by Chikarmane in this issue.

Pregnancy-associated Breast Cancer: Why Breast Imaging During Pregnancy and Lactation Matters

Pregnancy-associated breast cancer is characterized as breast cancer diagnosed during pregnancy, within the first postpartum year, or during lactation. It usually presents as a palpable mass, although the large majority of palpable masses during pregnancy are benign. Breast cancer is the most common invasive malignancy diagnosed during pregnancy and lactation, and its incidence is increasing as more women delay childbearing. Understanding the appropriate methods for screening and diagnostic workup of breast findings in this population is imperative for radiologists to promptly diagnose pregnancy-associated breast cancer. Use of available imaging modalities should be tailored to patient-specific factors, with US typically the first-line modality due to patient age and decreased sensitivity of mammography in the setting of lactational changes. This article illustrates the spectrum of imaging appearances of pregnancy-associated breast cancer, the appropriate diagnostic imaging workup, and the unique challenges encountered in evaluation of this patient population.

Ultrafast DCE-MRI for discriminating pregnancy-associated breast cancer lesions from lactation related background parenchymal enhancement

OBJECTIVE

To investigate the utility of ultrafast dynamic-contrast-enhanced (DCE) MRI in visualization and quantitative characterization of pregnancy-associated breast cancer (PABC) and its differentiation from background-parenchymal-enhancement (BPE) among lactating patients.

MATERIALS AND METHODS

Twenty-nine lactating participants, including 10 PABC patients and 19 healthy controls, were scanned on 3-T MRI using a conventional DCE protocol interleaved with a golden-angle radial sparse parallel (GRASP) ultrafast sequence for the initial phase. The timing of the visualization of PABC lesions was compared to lactational BPE. Contrast-noise ratio (CNR) was compared between the ultrafast and conventional DCE sequences. The differences in each group's ultrafast-derived kinetic parameters including maximal slope (MS), time to enhancement (TTE), and area under the curve (AUC) were statistically examined using the Mann-Whitney test and receiver operator characteristic (ROC) curve analysis.

RESULTS

On ultrafast MRI, breast cancer lesions enhanced earlier than BPE (p < 0.0001), enabling breast cancer visualization freed from lactation BPE. A higher CNR was found for ultrafast acquisitions vs. conventional DCE (p < 0.05). Significant differences in AUC, MS, and TTE values were found between the tumor and BPE (p < 0.05), with ROC-derived AUC of 0.86 ± 0.06, 0.82 ± 0.07, and 0.68 ± 0.08, respectively. The BPE grades of the lactating PABC patients were reduced as compared with the healthy lactating controls (p < 0.005).

CONCLUSION

Ultrafast DCE MRI allows BPE-free visualization of lesions, improved tumor conspicuity, and kinetic quantification of breast cancer during lactation. Implementation of this method may assist in the utilization of breast MRI for lactating patients.

CLINICAL RELEVANCE

The ultrafast sequence appears to be superior to conventional DCE MRI in the challenging evaluation of the lactating breast. Thus, supporting its possible utilization in the setting of high-risk screening during lactation and the diagnostic workup of PABC.

KEY POINTS

• Differences in the enhancement slope of cancer relative to BPE allowed the optimal visualization of PABC lesions on mid-acquisitions of ultrafast DCE, in which the tumor enhanced prior to the background parenchyma. • The conspicuity of PABC lesions on top of the lactation-related BPE was increased using an ultrafast sequence as compared with conventional DCE MRI. • Ultrafast-derived maps provided further characterization and parametric contrast between PABC lesions and lactation-related BPE.

Breast Imaging and Intervention during Pregnancy and Lactation

Physiologic changes that occur in the breast during pregnancy and lactation create challenges for breast cancer screening and diagnosis. Despite these challenges, imaging evaluation should not be deferred, because delayed diagnosis of pregnancy-associated breast cancer contributes to poor outcomes. 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. US is the preferred initial imaging modality for the evaluation of clinical symptoms in pregnant women, followed by mammography if the US findings are suspicious for malignancy or do not show the cause of the clinical symptom. Breast MRI is not recommended during pregnancy because of the use of intravenous gadolinium-based contrast agents. Diagnostic imaging for lactating women is the same as that for nonpregnant nonlactating individuals, beginning with US for patients younger than 30 years old and mammography followed by US for patients aged 30 years and older. MRI can be performed for high-risk screening and local-regional staging in lactating women. The radiologist may encounter a wide variety of breast abnormalities, some specific to pregnancy and lactation, including normal physiologic changes, benign disorders, and malignant neoplasms. Although most masses encountered are benign, biopsy should be performed if the imaging characteristics are suspicious for cancer or if the finding does not resolve after a short period of clinical follow-up. Knowledge of the expected imaging appearance of physiologic changes and common benign conditions of pregnancy and lactation is critical for differentiating these findings from pregnancy-associated breast cancer. ©RSNA, 2023 Online supplemental material is available for this article. Quiz questions for this article are available through the Online Learning Center.

MRI can accurately diagnose breast cancer during lactation

OBJECTIVE

To test the diagnostic performance of breast dynamic contrast-enhanced (DCE) MRI during lactation.

MATERIALS AND METHODS

Datasets of 198 lactating patients, including 66 pregnancy-associated breast cancer (PABC) patients and 132 controls, who were scanned by DCE on 1.5-T MRI, were retrospectively evaluated. Six blinded, expert radiologists independently read a single DCE maximal intensity projection (MIP) image for each case and were asked to determine whether malignancy was suspected and the background-parenchymal-enhancement (BPE) grade. Likewise, computer-aided diagnosis CAD MIP images were independently read by the readers. Contrast-to-noise ratio (CNR) analysis was measured and compared among four consecutive acquisitions of DCE subtraction images.

RESULTS

For MIP-DCE images, the readers achieved the following means: sensitivity 93.3%, specificity 80.3%, positive-predictive-value 70.4, negative-predictive-value 96.2, and diagnostic accuracy of 84.6%, with a substantial inter-rater agreement (Kappa = 0.673, p value < 0.001). Most false-positive interpretations were attributed to either the MIP presentation, an underlying benign lesion, or an asymmetric appearance due to prior treatments. CAD's derived diagnostic accuracy was similar (p = 0.41). BPE grades were significantly increased in the healthy controls compared to the PABC cohort (p < 0.001). CNR significantly decreased by 11-13% in each of the four post-contrast images (p < 0.001).

CONCLUSION

Breast DCE MRI maintains its high efficiency among the lactating population, probably due to a vascular-steal phenomenon, which causes a significant reduction of BPE in cancer cases. Upon validation by prospective, multicenter trials, this study could open up the opportunity for breast MRI to be indicated in the screening and diagnosis of lactating patients, with the aim of facilitating an earlier diagnosis of PABC.

KEY POINTS

• A single DCE MIP image was sufficient to reach a mean sensitivity of 93.3% and NPV of 96.2%, to stress the high efficiency of breast MRI during lactation. • Reduction in BPE among PABC patients compared to the lactating controls suggests that several factors, including a possible vascular steal phenomenon, may affect cancer patients. • Reduction in CNR along four consecutive post-contrast acquisitions highlights the differences in breast carcinoma and BPE kinetics and explains the sufficient conspicuity on the first subtracted image.

Cancer in pregnancy: breast cancer

Breast cancer is the most common malignancy in women, and for women under 40, it is the leading cause of cancer-related deaths. A specific type of breast cancer is pregnancy-associated breast cancer, which is diagnosed during pregnancy, the first-year postpartum, or during lactation. Pregnancy-associated breast cancer is seen in 3/1000 pregnancies and is increasing in incidence as women delay pregnancy. This type of breast cancer is more aggressive, and not infrequently, there is a delay in diagnosis attributed to physiologic changes that occur during pregnancy and a lack of awareness among physicians. In this review, we discuss the demographics of pregnancy-associated breast cancer, provide differential considerations, and illustrate the multimodality imaging features to bring attention to the radiologist about this aggressive form of breast cancer.

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.

Non-BRCA Early-Onset Breast Cancer in Young Women

The incidence of breast cancer in younger women is rising. Although early-onset breast cancer is highly associated with biologically aggressive tumors such as triple-negative and human epidermal growth factor 2 (HER2)-positive cancers, the more recent increase is disproportionately driven by an increase in the incidence of luminal cancer. In particular, the increase in de novo stage IV disease and the inherent age-based poorer survival rate among younger women with even early-stage luminal cancers suggest underlying distinct biologic characteristics that are not well understood. Further contributing to the higher number of early-onset breast cancers is pregnancy-associated breast cancer (PABC), which is attributed to persistent increases in maternal age over time. Although guidelines for screening of patients who carry a BRCA1 or BRCA2 gene mutation are well established, this population comprises only a fraction of those with early-onset breast cancer. A lack of screening in most young patients precludes timely diagnosis, underscoring the importance of early education and awareness. The disproportionate disease burden in young women of certain racial and ethnic groups, which is further exacerbated by socioeconomic disparity in health care, results in worse outcomes. An invited commentary by Monticciolo is available online. ^©RSNA, 2022.

MRI of the Lactating Breast: Computer-Aided Diagnosis False Positive Rates and Background Parenchymal Enhancement Kinetic Features

RATIONALE AND OBJECTIVES

To investigate the application of computer-added diagnosis (CAD) in dynamic contrast-enhanced (DCE) MRI of the healthy lactating breast, focusing on false-positive rates and background parenchymal enhancement (BPE) coloring patterns in comparison with breast cancer features in non-lactating patients.

MATERIALS AND METHODS

The study population was composed of 58 healthy lactating patients and control groups of 113 healthy premenopausal non-lactating patients and 55 premenopausal non-lactating patients with newly-diagnosed breast cancer. Patients were scanned on 1.5-T MRI using conventional DCE protocol. A retrospective analysis of DCE-derived CAD properties was conducted using a commercial software that is regularly utilized in our routine radiological work-up. Qualitative morphological characterization and automatically-obtained quantitative parametric measurements of the BPE-induced CAD coloring were categorized and subgroups' trends and differences between the lactating and cancer cohorts were statistically assessed.

RESULTS

CAD false-positive coloring was found in the majority of lactating cases (87%). Lactation BPE coloring was characteristically non-mass enhancement (NME)-like shaped (87%), bilateral (79%) and symmetric (64%), whereas, unilateral coloring was associated with prior irradiation (p <0.0001). Inter-individual variability in CAD appearance of both scoring-grade and kinetic-curve dominance was found among the lactating cohort. When compared with healthy non-lactating controls, CAD false positive probability was significantly increased [Odds ratio 40.2, p <0001], while in comparison with the breast cancer cohort, CAD features were mostly inconclusive, even though increased size parameters were significantly associated with lactation-BPE (p <0.00001).

CONCLUSION

BPE was identified as a common source for false-positive CAD coloring on breast DCE-MRI among lactating population. Despite several typical characteristics, overlapping features with breast malignancy warrant a careful evaluation and clinical correlation in all cases with suspected lactation induced CAD coloring.

Pregnancy-lactation cycle: how to use imaging methods for breast evaluation

Pregnancy and lactation constitute states of intense hormonal variation with secretory and structural changes in the breast parenchyma. These changes translate into important features on breast imaging, as well as the emergence of specific benign and malignant lesions. This literature review aims to discuss the safety of the use of breast imaging methods (mammography, ultrasound, and magnetic resonance imaging) during the pregnancy-lactation cycle, and to present the expected physiological changes and imaging appearance of the main breast diseases that may occur in this period, such as galactocele, lactating adenoma, fibroadenoma, puerperal mastitis, and pregnancy-associated breast cancer.

Breast Imaging in Pregnancy and Lactation

All breast disorders found during pregnancy and lactation should be carefully evaluated. Most of them are benign, but it is essential to exclude pregnancy-associated breast cancer (PABC), which is too often diagnosed late. The first-line imaging technique is ultrasound (US), which must be completed by mammography if there is any clinical or US suspicious sign . In lactating patients with PABC , breast magnetic resonance imaging (MRI) can be useful for local assessment.Management depends on the precise analysis and BI-RADS classification of the lesion. During pregnancy and lactation, there is an overlap in imaging: many benign lesions can grow, infarct, become heterogeneous and thus suspicious, and on the other hand, PABC does not always present with typical malignant features. That is why biopsy must be performed if after the clinical and radiological evaluation the doubt persists, i.e. for all BI-RADS 4 and 5 lesions, and for some BI-RADS 3 lesions.

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.

Physiologic and hypermetabolic breast 18-F FDG uptake on PET/CT during lactation

OBJECTIVE

To investigate the patterns of breast cancer-related and lactation-related ¹⁸F-FDG uptake in breasts of lactating patients with pregnancy-associated breast cancer (PABC) and without breast cancer.

METHODS

¹⁸F-FDG-PET/CT datasets of 16 lactating patients with PABC and 16 non-breast cancer lactating patients (controls) were retrospectively evaluated. Uptake was assessed in the tumor and non-affected lactating tissue of the PABC group, and in healthy lactating breasts of the control group, using maximum and mean standardized uptake values (SUVmax and SUVmean, respectively), and breast-SUVmax/liver-SUVmean ratio. Statistical tests were used to evaluate differences and correlations between the groups.

RESULTS

Physiological uptake in non-breast cancer lactating patients' breasts was characteristically high regardless of active malignancy status other than breast cancer (SUVmax = 5.0 ± 1.7, n = 32 breasts). Uptake correlated highly between the two breasts (r = 0.61, p = 0.01), but was not correlated with age or lactation duration (p = 0.24 and p = 0.61, respectively). Among PABC patients, the tumors demonstrated high ¹⁸F-FDG uptake (SUVmax = 7.8 ± 7.2, n = 16), which was 326-643% higher than the mostly low physiological FDG uptake observed in the non-affected lactating parenchyma of these patients (SUVmax = 2.1 ± 1.1). Overall, ¹⁸F-FDG uptake in lactating breasts of PABC patients was significantly decreased by 59% (p < 0.0001) compared with that of lactating controls without breast cancer.

CONCLUSION

¹⁸F-FDG uptake in lactating tissue of PABC patients is markedly lower compared with the characteristically high physiological uptake among lactating patients without breast cancer. Consequently, breast tumors visualized by ¹⁸F-FDG uptake in PET/CT were comfortably depicted on top of the background ¹⁸F-FDG uptake in lactating tissue of PABC patients.

KEY POINTS

• FDG uptake in the breast is characteristically high among lactating patients regardless of the presence of an active malignancy other than breast cancer. • FDG uptake in non-affected lactating breast tissue is significantly lower among PABC patients compared with that in lactating women who do not have breast cancer. • In pregnancy-associated breast cancer patients, ¹⁸F-FDG uptake is markedly increased in the breast tumor compared with uptake in the non-affected lactating tissue, enabling its prompt visualization on PET/CT.

Predicting the likelihood of recurrence of pregnancy-associated breast cancer: Nomogram based on analysis of the French cancer network: Cancer Associé à La Grossesse

OBJECTIVE

Pregnancy associated breast cancer (PABC) are defined as breast cancer diagnosed during pregnancy and during the year following delivery. The prediction of poor prognosis events (PPE) such as recurrence is a major medical challenge of management for women with PABC. The aim of this study was to build a nomogram based on selected clinical and histological variables to predict recurrence.

STUDY DESIGN

This retrospective study included 96 patients with PABC from January 2002 to January 2018. A multivariate Cox analysis of selected risk factors was performed and a nomogram to predict recurrence was built. The nomogram was internally validated.

RESULTS

The overall recurrence rate was 22% (21/95) and the 3-years recurrence rate was 13% (12/95). Age at diagnosis, histological type, immuno-histological class, tumor stage (TNM), node stage (TNM) were associated with PPE in univariate analysis, and were included in the final Cox model to develop the nomogram. The predictive model had a concordance index of 0.83 (95% Confidence Interval (CI), 0.81-0.85) and 0.78 (95% CI, 0.76-0.80) before and after the 200 repetitions of bootstrap sample corrections, respectively, and showed a good calibration.

CONCLUSION

Our results support the use of the present nomogram based on 5 clinical and pathological characteristics to predict PPE in PABC with a high concordance. External validation is required to recommend this nomogram in routine practice.

Pregnancy-associated breast cancer: A review of 47 women

PURPOSE

Pregnancy-associated breast cancer (PABC) is a rare disease. However, its expected incidence tends to be increased because of delayed maternal age. The purpose of this study was to describe the clinical, radiological, and histopathological characteristics of PABC cases diagnosed in our center.

METHODS

The clinical-radiological findings and histopathological characteristics of patients diagnosed and treated with PABC at our institution between January 2011 and January 2017 were retrospectively evaluated.

RESULTS

Mammography and ultrasonography were performed in all patients. MRI examination was performed in 18 patients. Nine (19.1%) out of 47 patients were diagnosed with breast cancer during pregnancy, and 38 (80.9%) were in their first year after delivery. The most frequent finding (95.7%) during imaging was one or more masses. Mammography-detected pure or accompanying microcalcifications were found in 12 (25.5%) patients. MRI detected additional multifocal and multicentric disease in 14 (29.8%) patients and contralateral cancer in one (2.1%) patient.

CONCLUSIONS

Pregnancy-related breast cancer tends to be diagnosed in an advanced stage with poor prognosis. Any breast abnormalities observed in this period should alert clinicians, and a meticulous radiological evaluation is mandatory. The early diagnosis of this disease would increase the chances of successful treatment.

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.

Imaging in pregnancy-associated breast cancer: a case report

BACKGROUND

PABC (pregnancy-associated breast cancer) is a rare condition that appears as a malignancy in 1 per 3000 pregnant women and is one of the most common cancers diagnosed during pregnancy or the postpartum period. If a woman who is pregnant or within a year after delivery has complaints of a palpable breast mass, it could undeniably be a malignant mass of the breast. That is why an ultrasound should be performed for all pregnant or lactating women who detect a palpable breast mass that persists for two or more weeks.

CASE REPORT

Our case report presents a pregnant 40-year-old previously healthy female at 36 weeks gestational age with a complaint of a palpable left breast mass for two months period. The initial ultrasound showed a breast tumour of irregular shape, solid and hypervascular mass.

CONCLUSIONS

Early diagnostics of PABC is of crucial importance in order to offer the best possible outcomes for the patient and foetus.

Cancer in pregnancy

The incidence of cancer in pregnancy is increasing. The most frequent malignancies include breast and cervical cancers. Diagnosis may be complicated by late presentation. Imaging during pregnancy should consider risks to the fetus. Diagnostic work-up, including tumor markers, can be influenced by the physiology of pregnancy. Treatment of cancer can often be safely administered with good maternal and fetal outcomes. Chemotherapy, radiotherapy, and surgery must be adapted to the pregnancy state. Counselling and emotional support are an essential part of management.

Propensity score to evaluate prognosis in pregnancy-associated breast cancer: Analysis from a French cancer network

PURPOSE

To compare the prognosis of pregnancy associated breast cancer occurring during pregnancy (BCP) to non-pregnancy associated breast cancers (non-BCP) in young women managed at a national expert center.

METHODS

Retrospective cohort study of a prospective database using propensity score matching (PSM) analysis with known prognostic factors.

RESULTS

We analyzed data of 49 patients with BCP and 104 with non-BCP diagnosed between 2002 and 2017 at Tenon University Hospital (Paris, France). The BCP tumors were often locally advanced (lymph node metastases in 59%), of high grade (55%) and highly proliferative (67% with Ki67 ≥ 20%). After PSM, breast cancer-free survival (p = 0.45) and breast cancer specific survival (p = 0.81) were similar in the two groups. The recurrence rate was 12% vs 18% (p = 0.45) and the death rate was 6% vs 8% (p = 0.74) for the BCP and non-BCP groups, respectively. No difference in recurrence type was observed between the groups (p = 0.60).

CONCLUSIONS

After PSM for known prognostic factors, the prognosis of BCP patients did not differ from that of young patients with non-BCP.