A single-institution study of 117 pregnancy-associated breast cancers (PABC): Presentation, imaging, clinicopathological data and outcome

Risk factors for the increasing incidence of pregnancy-associated cancer in Sweden - a population-based study

INTRODUCTION

The incidence of cancer during pregnancy and within first year post-delivery, ie pregnancy-associated cancer (PAC), is increasing in many countries, but little is known about risk factors for these trends. This study quantified incidence of PAC by trimesters and post-delivery periods, and assessed the role of maternal age, parity, immigrant status, education, smoking and body mass index for the risk and incidence trends of PAC.

MATERIAL AND METHODS

We used data from the national birth and cancer registers in Sweden during 1973-2017 to define a register-based cohort of women aged 15-44 years. Incidence rates of PAC during pregnancy and up to 1 year post-delivery were calculated per 100 000 deliveries per year. Poisson regression with multiple imputation estimated incidence rate ratios with 95% confidence intervals adjusted by year, age, previous parity, immigrant status, education, smoking and BMI during 1990-2017, when information on risk factors was available.

RESULTS

Among 4 557 284 deliveries, a total of 1274 (during pregnancy) and 3355 (within 1 year post-delivery) cases of PAC were diagnosed, with around 50 cases/year diagnosed during pregnancy and 110 cases/year during the first year post-delivery in the latest period 2015-2017. The most common cancer types during pregnancy were malignant melanoma, breast and cervical cancer, together accounting for 57% of cases during pregnancy and 53% during the first year post-delivery. The numbers of PAC were lower during pregnancy than during post-delivery for all tumor types with lowest numbers during first trimester. The PAC incidence rates increased over calendar time. High maternal age at diagnosis, smoking, nulliparity and non-immigrant background were associated with significantly higher risks of PAC. The increasing PAC incidence was in part explained by higher maternal age over time, but not by the other factors.

CONCLUSIONS

High maternal age is the strongest risk factor for PAC. We show for the first time that smoking, nulliparity and non-immigrant background are also contributing risk factors for PAC. However, only high maternal age contributed significantly to the increasing incidence. Further studies on other potential risk factors for PAC are warranted, since our results indicate that age on its own does not fully explain the increase.

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.

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.

The mutational landscape of the adult healthy parous and nulliparous human breast

The accumulation of somatic mutations in healthy human tissues has been extensively characterized, but the mutational landscape of the healthy breast is still poorly understood. Our analysis of whole-genome sequencing shows that in line with other healthy organs, the healthy breast during the reproduction years accumulates mutations with age, with the rate of accumulation in the epithelium of 15.24 ± 5 mutations/year. Both epithelial and stromal compartments contain mutations in breast-specific driver genes, indicative of subsequent positive selection. Parity- and age-associated differences are evident in the mammary epithelium, partly explaining the observed difference in breast cancer risk amongst women of different childbearing age. Parity is associated with an age-dependent increase in the clone size of mutated epithelial cells, suggesting that older first-time mothers have a higher probability of accumulating oncogenic events in the epithelium compared to younger mothers or nulliparous women. In conclusion, we describe the reference genome of the healthy female human breast during reproductive years and provide evidence of how parity affects the genomic landscape of the mammary gland.

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.

Imaging Cancer in Pregnancy

Pregnancy-associated cancer (PAC) is defined as cancer that is detected during pregnancy and up to 1 year postpartum. Although rare (~1:1000 pregnancies), PAC is increasing owing to postponed childbearing and advanced maternal age at conception. Cancer-related symptoms masked by physiologic gestational changes may delay diagnosis. Imaging, clinical management, and treatment require a carefully choreographed multidisciplinary team approach. The risk-benefit of every imaging modality, the strategies to balance the safety of mother and fetus, and the support of the patient and family at every step are crucial. US and MRI are preferred imaging modalities that lack ionizing radiation. Radiation dose concerns should be addressed, noting that most imaging examinations (including mammography, radiography, CT, and technetium 99m-labeled sulfur colloid sentinel lymph node staging) are performed at radiation levels below thresholds at which deterministic side effects are seen. Dose estimates should be provided after each examination. The use of iodinated intravenous contrast material is safe during pregnancy, but gadolinium-based contrast material should be avoided. Accurate diagnosis and staging combined with gestational age affect decisions about surgery and chemotherapy. Whole-body MRI with diffusion-weighted sequences is ideal to screen for primary and metastatic sites, determine disease stage, identify biopsy targets, and guide further cancer site-specific imaging. The authors provide an update of the imaging triage, safety considerations, cancer-specific imaging, and treatment options for cancer in pregnancy. An invited commentary by Silverstein and Van Loon is available online. Online supplemental material is available for this article. ^©RSNA, 2022.

Ultrasound features of pregnancy-associated breast cancer: A retrospective observational analysis

Pregnancy-associated breast cancer (PABC) is a poor prognosis in women, and the mortality rate is higher in this subgroup of patients than in non-PABC. This study aims to assess clinicopathological and ultrasound features of patients with PABC. Of 75 patients with breast cancer, 31 cases were in lactating, or pregnancy phase and 44 patients had no recent history of pregnancy/lactation at the time of cancer detection. The available pathological characteristics and ultrasound findings of the PABC and non-PABC groups were compared. The analysis of ultrasound findings demonstrated that the percentages of antiparallel orientation (p = 0.04) and heterogeneous internal echo pattern (p = 0.002) were higher in the PABC group. The final Breast Imaging Reporting and Data System (BI-RADS) assessment in the two groups was significantly different (p = 0.008). In this study, most PABCs were BI-RADS 4c or 5; compared with age-matched non-PABC cases. There were significant differences in ER (p = 0.03), receptor groups (p = 0.007), and tumor grade (p = 0.02) in PABC compared to non-PABC group. To conclude, radiologists should be careful about ultrasound findings of PABC and recommend core needle biopsy in suspected cases.

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.

Prognosis of pregnancy-associated breast cancer: inferior outcome in patients diagnosed during second and third gestational trimesters and lactation

PURPOSE

Pregnancy-associated breast cancer, although most commonly defined as breast cancer diagnosed during pregnancy or ≤1 year following delivery, knows a variety of definitions, likely related to the diversity of reported clinicopathological features and prognosis. More insight into the different breast cancer subgroups during pregnancy, time after delivery and the postpartum period is therefore warranted.

METHODS

Patients with breast cancer diagnosed during pregnancy or ≤6 months postdelivery were included, and subdivided according to gestational trimester, and postpartum patients according to lactational status. Subgroups were compared to matched non-PABC patients, to investigate the influence of pregnancy and lactation on clinical course and outcome.

RESULTS

Overall, 662 PABC patients were included (median age 34 years, median follow-up 6.5 years). PABC patients showed an advanced stage at diagnosis and an inferior 5-years-OS (75.4% vs. 83.2%, p = 0.000) compared to 1392 matched non-PABC patients. In subgroup analysis, first trimester PABC patients showed a significantly lower tumor size and stage as compared to other trimesters. Patients diagnosed during the first trimester and postpartum non-lactating patients had a relatively good OS (81.3% and 77.9%, respectively) versus patients diagnosed during the second and third trimesters and during lactation (OS 60.0%, 64.9% and 65.6%, respectively, p = 0.003).

CONCLUSION

In this large (uniquely specified) PABC cohort, an inferior outcome was found for patients diagnosed within the second and third gestational trimesters and during lactation. These findings indicate that PABC is clinically a heterogeneous group of breast cancer patients that should be redefined based on trimester of diagnosis and lactational status.

Clinical Decision Making in the Management of Breast Cancer Diagnosed During Pregnancy: A Review and Case Series Analysis

Purpose: To highlight the various options available for the management of breast cancer diagnosed during pregnancy by describing the investigations, treatment, and outcomes in relation to these women. Methods: This is a narrative review of the literature to describe the issues related to pregnancy and obstetric management in patients with breast cancer. It incorporates a description of six cases of women (aged 29-39 years) with a first-time diagnosis of breast cancer during pregnancy to illustrate a number of issues that need to be considered during different trimesters. Results: Of the six cases, two were diagnosed in each pregnancy trimester. A painless breast mass was the presenting symptom in five cases (83%). In all cases, breast ultrasound was the primary diagnostic imaging procedure. Chest X-ray was performed in 3 (50%) and computed tomography in 2 (33%). A core needle biopsy was performed in all cases, and sentinel lymph node biopsy in 3 (50%) cases. Four women had grade 3 tumor; five had estrogen receptor-positive tumors. Four women had breast surgery during pregnancy. Five women gave birth after the induction of labor and/or cesarean section. In all six cases, a multidisciplinary team was involved in the delivery of health care. Conclusion: Regular breast examinations are needed for all pregnant woman during prenatal visits. Breast ultrasonography should be offered if a breast lump or other symptoms are detected. Breast surgery can be safely performed during all pregnancy trimesters, and some systemic therapeutic agents can be administered safely in the second and third trimesters.

The Value of Targeted Ultrasound for the Primary Evaluation of Breast Symptoms in Pregnant Women of All Ages

OBJECTIVE

Data on breast imaging in symptomatic pregnant women are limited. Our aim was to assess the value of targeted breast US for the primary evaluation of breast symptoms in pregnant women of all ages.

METHODS

This IRB-approved retrospective study included all pregnant patients who underwent targeted US for focal breast symptoms at an academic imaging facility over an 18-year period (2000-2018). Clinical, imaging, and pathology results were reviewed. Malignant outcomes were determined by histology. Benign outcomes were confirmed by pathology or ≥2 years of follow-up. Descriptive statistics and 2 × 2 contingency table analyses were performed at the presentation level.

RESULTS

The study cohort comprised 178 presentations in 175 pregnant women. Mean age was 34.7 years (standard deviation, 5.2). The majority (153/178, 86.0%) were more than 30 years old. At presentation, 42.1% (75/178) were in the first trimester of pregnancy, 27.0% (48/178) in the second, and 29.8% (53/178) in the third. The most common presenting symptom was a palpable lump (162/178, 91.0%), followed by focal pain (7/178, 3.9%). The vast majority (174/178, 97.8%) of cases were non-malignant. However, targeted US detected all 4 malignancies (cancer detection rate, 22/1000; negative predictive value 136/136, 100%). Sensitivity and specificity were 100% (4/4) and 78.2% (136/174), respectively.

CONCLUSION

Benign causes of symptoms in pregnant women were far more common; malignancy was rare, accounting for only 2.2% (4/178) of cases. Targeted breast US detected all malignancies, supporting US as the primary imaging modality for evaluating symptomatic pregnant women, regardless of age.

Breast Cancer During Pregnancy: A Marked Propensity to Triple-Negative Phenotype

Breast and cervical cancers comprise 50% of all cancers during pregnancy. In particular, gestational breast cancer is considered one of the most aggressive types of cancers, which is a rare but fatal disease. However, the incidence of this type of cancer is increasing over the years and its prevalence is expected to rise further as more women delay childbearing. Breast cancer occurring after pregnancy is generally triple negative with specific characterizations of a poorer prognosis and outcome. On the other hand, it has been pointed out that this cancer is associated with a specific group of genes which can be used as precise targets to manage this deadly disease. Indeed, combination therapies consisting of gene-based agents with other cancer therapeutics is presently under consideration. We herein review recent progress in understanding the development of breast cancer during pregnancy and their unique subtype of triple negative which is the hallmark of this type of 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.

Pregnancy-Associated Breast Cancer: What Radiologists Must Know

Pregnancy-associated breast cancer (PABC) is defined as breast cancer diagnosed during pregnancy, in the first year postpartum, or during breastfeeding. Imaging techniques play a significant role in the diagnosis of PABC. It is a challenging diagnosis since physiological changes seen in pregnancy and breastfeeding may limit clinical suspicion and imaging utility. The patient's well-being and the fetus must be taken into consideration for diagnosis and treatment.

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.

Breast cancer during pregnancy: matched study of diagnostic approach, tumor characteristics, and prognostic factors

INTRODUCTION

Breast cancer is one of the most frequently occurring cancers during pregnancy and its incidence is increasing. Many studies have shown poor outcomes, the causes of which remain unclear.

OBJECTIVES

To analyze radiologic characteristics, histology, and prognosis factors of breast cancer during pregnancy.

METHODS

A total of 42 patients with breast cancer diagnosed during pregnancy (BCP) were matched with 84 patients with breast cancer of similar age who were not pregnant. Sensitivity of radiology, tumor characteristics, prognosis factors, disease-free survival, and overall survival were analyzed.

RESULTS

The sensitivity of breast ultrasound was higher than that of mammography for both groups. Ultrasound sensitivity for cancer was 95.7% in patients with BCP versus 98% in the not pregnant group, with non-statistically significant differences. Mammography sensitivity for cancer was 56.5% in patients with BCP versus 61% in the not pregnant group, with non-statistically significant differences. The stage at diagnosis according to the TNM staging system was significantly higher in patients with BCP with stage IV cancer: 16.7% in patients with BCP versus 3.7% in the not pregnant group (p = 0.03). No statistically significant differences were observed in histologic grade, Ki-67 index, or molecular subtype. Disease-free survival and overall survival were significantly lower in patients with BCP (p = 0.002 and p = 0.04). Multivariate analysis showed no difference when adjusting for stage and surrogate molecular subtype.

CONCLUSION

Breast ultrasound shows a high sensitivity to detect breast cancer during pregnancy. BCP is diagnosed at a higher stage than in nonpregnant women. In our series, patients with BCP had poorer outcomes than the not pregnant group. These results were not observed when adjusting for stage.

Atypical Lesions of the Breast and Lobular Carcinoma in Situ in Pregnancy - Surgeons' Practice

Objective

Approach to precancerous and high-risk breast lesions occurring in pregnancy has received little attention in the literature. We carried out a study to investigate the practice of surgeons in the management of these cases.

Materials and Methods

A short survey was sent to surgeons, including a multiple-choice questionnaire about their practice for atypical hyperplasia or lobular carcinoma in situ presenting in each trimester of pregnancy or at time of breastfeeding. Answer options included observation, immediate vacuum biopsy, immediate surgery, surgery in next trimester, surgery after delivery, and surgery after end of breastfeeding; based on the time of presentation.

Results

Out of the 671 practitioners invited, 97(14.5 %) responded to the survey. Participants were from 23 countries. Answers showed that management of gestational Atypical Ductal Hyperplasia (ADH) and Lobular Neoplasia (LN) was readily postponed by surgeons in favor of fetus safety while being cautious about risks of conservative management alone.

Conclusion

Various methods of treatment are selected by surgeons for managing high-risk breast lesions during pregnancy. In the absence of relevant literature, decision making in a multidisciplinary team would be the best approach in these cases.

Surgery for Pregnancy-Associated Breast Cancer

Surgery in the form of both mastectomy and breast conservation is the main step in the treatment of breast cancer. Numerous studies have shown an equivalent long-term survival for breast conserving surgery (BCS) and mastectomy . Patients desire and tumor characteristics, especially size and multicentricity, are the key factors that affect the decision between these two types of surgery . Patients with any contraindication for radiotherapy or previous history of radiation to the breast field are not suitable for BCS . There are few absolute contraindications for BCS , and early pregnancy is listed among them; mastectomy is preferred in the first trimester of pregnancy to avoid the impact of delaying radiation therapy on outcome of the cancer.

Breast Imaging During Pregnancy and Lactation

Breast imaging during pregnancy and lactation is important in order to avoid delays in the diagnosis and treatment of pregnancy-associated breast cancers. Radiologists have an opportunity to improve breast cancer detection by becoming familiar with appropriate breast imaging and providing recommendations to women and their referring physicians. Importantly, during pregnancy and lactation, both screening and diagnostic breast imaging can be safely performed. Here we describe when and how to screen, how to work up palpable masses, and evaluate bloody nipple discharge. The imaging features of common findings in the breasts of pregnant and lactating women are also reviewed. Finally, we address breast cancer staging and provide a brief primer on treatment options for pregnancy-associated breast cancers.

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.

Pregnancy-Associated Breast Cancer: A Realistic Approach

Background

The number of cancers diagnosed during pregnancy is on the rise, and breast cancer is the most common malignancy. Presently, there are very limited resources and no clear guidelines for managing this peculiar patient population both worldwide and in India. The objective of this study was to find out the incidence of pregnancy-associated breast cancer (PABC) in a tertiary care referral centre and to compare the epidemiological, diagnostic and prognostic factors as well as maternal and foetal outcomes with the most recent literature worldwide.

Methods

We conducted a retrospective descriptive study of women diagnosed with breast cancer in pregnancy and post-partum period at a tertiary care centre in southern India during the period of 10 years (total number of breast cancer patients were 10). We studied the diagnostic and prognostic factors as well as maternal and foetal outcome in patients diagnosed with breast cancer for the first time in pregnancy.

Results

Overall incidence of PABC was found to be 0.6% (n = 10). Mean age at the time of presentation was 30.7 ± 4 years. All cases suspected clinically or on imaging (USG) were confirmed with FNAC, excision biopsy or Trucut biopsy. Out of 10 patients, 70% (n = 7) had an advanced-stage disease on diagnosis. Histopathology suggested 90% (n = 9) had invasive ductal carcinoma and 55.5% (n = 5) had a triple negative receptor status. 20% (n = 2) of our patients had opted for a breast conservation surgery (BCS), and 70% (n = 7) of our patients underwent modified radical mastectomy with neoadjuvant or adjuvant chemotherapy/radiotherapy. One patient had a second trimester MTP in view of stage 4 disease. 77.7% (n = 7) of the nine patients who continued pregnancy underwent LSCS, out of which 57.4% (n = 4) were elective, and MRM was done concurrently with LSCS in 50% (n = 2) of the elective LSCS. The mean birth weight of the 9 neonates was 2.2 ± 0.5 kg. Intrauterine growth retardation was seen in 22.2% (n = 2) neonates. 33.3% (n = 3) of the neonates required NICU support, and one baby expired on post-natal day 16.

Conclusion

With the increasing number of elderly primigravida amongst the urban population, a clear understanding of PABC is becoming more important. A multidisciplinary team approach shall help the clinician not only in reducing the heavy burden of patient responsibility but more importantly, in guaranteeing better quality of treatment, avoiding unnecessary delays in providing interventions and providing adequate 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.

Clinicopathological characteristics, diagnosis, and prognosis of pregnancy-associated breast cancer

Background

The aim of this study was to evaluate the characteristics, diagnosis, prognosis, and effective treatment modalities of pregnancy‐associated breast cancer (PABC).

Methods

From 1 January 2005 to 31 December 2015, 142 patients with PABC were identified in the Cancer Institute and Hospital of Tianjin Medical University database. The clinicopathological features, treatment methods, and outcomes were retrospectively evaluated.

Results

The median age at diagnosis was 30 years. All patients presented with a palpable mass in the breast. The sensitivity of ultrasound and mammography in PABC diagnosis was 86% and 83.3%, respectively, which increased to 91.3% when a combination of mammography and ultrasound was used. The median tumor size was 5.5 cm, and 63.1% of patients had associated axillary lymph node metastases. The proportions of ER negative, PR negative and HER2 positive were 45.7%, 45.7% and 30%, respectively. The five‐year overall survival (OS) and disease‐free survival (DFS) rates were 76.8% and 63.5%, respectively. According to univariate analysis, T stage, N stage, and HER2 status were significant prognostic factors for OS and DFS. The time interval between the onset of the first symptom and the first meeting with a health professional was also significant for OS. Multivariate analysis showed that T stage and HER2 status were independent prognostic risk factors for OS and DFS.

Conclusion

PABC is an aggressive form of breast cancer associated with advanced stage at diagnosis. Despite the existing difficulties in diagnosis, imaging examinations are indispensable. Early diagnosis and multidisciplinary therapy, including anti‐HER2 targeted therapy, may be important to improve prognosis.

Combinatorial Electrophoresis and Mass Spectrometry-Based Proteomics in Breast Milk for Breast Cancer Biomarker Discovery

Innovations in approaches for early detection and individual risk assessment of different cancers, including breast cancer (BC), are needed to reduce cancer morbidity and associated mortality. The assessment of potential cancer biomarkers in accessible bodily fluids provides a novel approach to identify the risk and/or onset of cancer. Biomarkers are biomolecules, such as proteins, that are indicative of an abnormality or a disease. Human milk is vastly underutilized biospecimen that offers the opportunity to investigate potential protein BC-biomarkers in young, reproductively active women. As a first step, we have examined the entire protein pattern in human milk samples from breastfeeding mothers with cancer, who were diagnosed either before or after milk donation, and from women without cancer, using mass spectrometry (MS)-based proteomics.

Diagnostic pathways and management in women with pregnancy-associated breast cancer (PABC): no evidence of treatment delays following a first healthcare contact

Background

Women with pregnancy-associated breast cancer (PABC), i.e. diagnosed during or within 2 years of pregnancy, have a poor prognosis. We compared symptoms, diagnostics, treatments, and waiting times from first symptoms to treatment initiation in women diagnosed with PABC and non-PABC.

Materials and methods

Women diagnosed with PABC and non-PABC at ages 15–44 were identified in Swedish healthcare registers. Chart information was retrieved for 546 women (273 PABC cases and 273 age- and hospital-matched non-PABC controls) treated at 11 hospitals across Sweden between 1992 and 2009. Distributions of symptoms, diagnostics and treatments were compared. Median waiting times from initial symptoms to start of treatment, and time periods within, were estimated from Kaplan–Meier curves.

Results

Initial symptoms in women with PABC and non-PABC were similar. Women with PABC more often underwent biopsy and ultrasound than mammography at initial examination. Compared to non-PABC, rates of mastectomy and axillary clearance were higher in women with PABC, while endocrine treatment was less common. The time from symptoms to first healthcare contact was non-significantly longer in women diagnosed during or within 6 months of pregnancy. Waiting times from contact with healthcare to diagnosis and treatment were shorter or similar in women with PABC compared to women with non-PABC.

Conclusions

These findings do not support the notion that diagnostic and treatment delays following a first healthcare contact are more common in women diagnosed with breast cancer during or shortly after pregnancy. However, there was some evidence of delays in seeking healthcare among pregnant and lactating women.

Electronic supplementary material

The online version of this article (10.1007/s10549-018-05083-x) contains supplementary material, which is available to authorized users.

Association of pregnancy and mortality in women diagnosed with breast cancer: A Nationwide Population Based Study in Taiwan

We examined the associations between breast cancer diagnosed during pregnancy and up to 5 years postpartum and total mortality. Breast cancer patients were identified from the Taiwan Cancer Registry (2002-2014). All pregnancies up to 5 years before breast cancer diagnosis were abstracted from the National Health Insurance database and data were then linked to the Taiwan National Death Certificate Database. Follow-up was calculated from the date of breast cancer diagnosis to the date of death or 31 December, 2014, whichever came first. The hazard ratios (HRs) and the 95% confidence intervals (CI) of the association between pregnancy and total mortality were estimated using Cox proportional hazard models. Among the 30,230 breast cancer patients, 90 were diagnosed during pregnancy, 347 within a year postpartum, and 1993 during 1-5 years postpartum. By the end of 2014, 2,920 patients were dead. The major cause of death was breast cancer (89%). Compared to patients without pregnancy records, the HRs were 1.42 (95% CI = 0.83-2.45) for patients diagnosed during pregnancy, 1.29 (0.96-1.74) for those diagnosed within a year postpartum, 1.27 (0.95-1.70) for those diagnosed within 1 to 2 years postpartum, and 1.06 (0.88-1.27) for those diagnosed ≥2 to 5 years postpartum, after adjustment for tumor characteristics and treatment. Subgroup analyses revealed an increased risk of mortality for patients diagnosed within a year postpartum in ER+ cancers (HR = 2.11, 95% CI = 1.28-3.47). Our results suggested a recent pregnancy may be associated with higher mortality among ER+ patients.

Pregnancy-associated breast cancer: maternal breast cancer survival over 10 years and obstetrical outcome at a university centre of women's health

PURPOSE

Pregnancy-associated breast cancer (PABC) is considered the second most common malignancy affecting pregnancy. The limited knowledge as to long-term survival is nonuniform. This retrospective study aims to contribute by a follow-up of pregnancies of breast cancer patients treated at a single university centre with focus on maternal long-term survival in relation to time point of diagnosis (before, during, and after pregnancy).

METHODS

Data of 25 patients were reviewed for the period between 2000 and 2009 in relation to their neonatal and maternal outcome parameters as well as their maternal breast cancer outcomes by assessing maternal mortality at annual intervals up to a maximum of 10 years follow-up.

RESULTS

Median age at diagnosis was 33 years. Maternal survival rate of the total collective came to 76% after 5 years and to 68% after 10 years. The newborns were healthy, 22% of them presented with a 1'Apgar score 5-7. Preterm delivery occurred in 53%. PABC significantly affected maternal survival compared to the national breast cancer cohort at 5 years and barely significantly at 10 years, with highly significant (p < 0.003) to significant (p < 0.01) effects at 5 and 10 years, respectively, for PABC diagnosed during and after pregnancy.

CONCLUSIONS

The present findings on survival rates suggest that maternal medical assessment at the beginning of and during further course of pregnancy should include a scrutinized thorough breast examination. Conveying/delivering special competences to monitor these high-risk pregnancies at the interface of oncological care should be considered an obligatory part of academic medical education, obstetrical training and interprofessional midwifery education.

Pregnancy-associated breast cancer: the risky status quo and new concepts of predictive medicine

The paper is motivated by severe concerns regarding currently applied care of the pregnancy-associated breast cancer (PABC) characterised by particularly poor outcomes of the disease. Psychological and ethical aspects play a crucial role in PABC: the highest priority not to damage the foetus significantly complicates any treatment generally, and it is quite usual that patients disclaim undergoing any breast cancer treatment during pregnancy. Although, due to global demographic trends, PABC is far from appearing rarely now, severe societal and economic consequences of the disease are still neglected by currently applied reactive medical approach. These actualities require creating new strategies which should be better adapted to the needs of the society at large by advancing the PABC care based on predictive diagnostic approaches specifically in premenopausal women, innovative screening programmes focused on young female populations, targeted prevention in high-risk groups, and optimised treatment concepts. The article summarises the facts and provides recommendations to advance the field-related research and medical services specifically dedicated to the PABC care.

Does anthracycline-based chemotherapy in pregnant women with cancer offer safe cardiac and neurodevelopmental outcomes for the developing fetus?

BACKGROUND

Cancer treatment during pregnancy is a growing problem especially now that women delay childbearing. Systemic treatment of these malignancies during pregnancy centers mainly on the anticancer drugs anthracyclines, widely used in treating hematological and breast cancer during pregnancy and sometimes associated with early and late toxicity for the fetus. Owing to concern about their cardiac and neurodevelopmental toxicity more information is needed on which anthracycline to prefer and whether they can safely guarantee a cardiotoxicity-free outcome in the fetus.

DISCUSSION

The major research findings underline anthracycline-induced dose-dependent effects, including cardiotoxicity, many avoidable. Partly because the placenta acts mainly as a barrier, research findings indicate low transplacental anthracycline transfer. Anthracycline-induced teratogenicity depends closely on when patients receive chemotherapy. Anthracycline cardiac toxicity may depend on the association with drugs that inhibit or induce placental P-glycoprotein (P-gp). P-gp-induced drug interactions may alter placental P-gp barrier function and subsequently change fetal exposure. Though many anthracyclines have acceptable safety profiles clinical studies suggest giving idarubicin with special caution. Patients and doctors who care for pregnant women should whenever possible avoid prematurity and hence reduce prematurity-induced medical complications at birth and in the long-term. Information is lacking on long-term anthracycline-induced effects.

CONCLUSION

Pregnant women receiving anthracycline-based chemotherapy should undergo regular, state-of-the-art diagnostic imaging to detect fetal drug-induced cardiac damage early, and allow alternative therapeutic options. Recognizing drug-induced interactions and understanding the most vulnerable fetuses will help in choosing tailored therapy. Future research on placental transport, blood-brain barrier drug passage and pharmacokinetics will improve the way we manage these difficult-to-treat patients and their fetuses.

Breast Cancer in Pregnancy: Avoiding Fetal Harm When Maternal Treatment Is Necessary

The management of breast cancer during pregnancy poses unique challenges and requires a multi-disciplinary approach. In this review, we discuss the treatment of breast cancer in pregnancy and recent updates regarding the safety of surgical and chemotherapeutic treatments, including both oncologic and fetal outcomes. The treatment of breast cancer during pregnancy mirrors that outside of pregnancy, with a few important differences dictated by the balance of maternal versus fetal health. Overall, surgical treatment, neo-adjuvant chemotherapy, and/or adjuvant chemotherapy are feasible in most women during pregnancy. Further research to determine the safety of these therapies in pregnancy-associated breast cancer is warranted.

Pregnancy Associated Breast Cancer: Awareness is the Key to Diagnosis -A Case Report

Pregnancy-associated breast cancer (PABC) is defined as breast cancer that occurs during pregnancy or within one year of delivery. PABCs are typically found at advanced stage and are reported to have higher recurrence and mortality rates as compared to non PABC. Although it is said to be rare its incidence is increasing. Very little data is available on PABC among Indian women. Delay in diagnosis is one of the major causes of aggressive presentation of PABC. This is due to the fact that most of the lesions presenting during this period are benign and lactational changes hamper the detection of mass clinically as well as by various investigative methods. Paget's disease of breast, usually reported in elderly woman, when occurs in lactating breast may mimic benign eczematous lesion. Increased awareness among patients as well as clinicians is required to detect this highly aggressive form of breast cancer at an early and treatable stage. Treatment is by multidisciplinary approach and depends upon the gestational stage. Here we report a case of PABC in a lactating woman presenting with Paget's disease because such case may be under diagnosed as breast feeding related lesion leading to delayed diagnosis.

High incidence of triple negative breast cancers following pregnancy and an associated gene expression signature

Breast cancer risk increases transiently in the period following pregnancy; pregnancy-associated breast cancers (PABC) are more aggressive than cases diagnosed in nulliparous women. We have previously reported that in the normal human breast pregnancy results in the upregulation of a number of inflammation related genes, suggesting a pro-tumorigenic environment as well as downregulation of ESR1 (ERα) and ERBB2 (HER2) and upregulation of ESR2 (ERβ), suggesting a protective effect. In this study, we aimed to investigate the possibility of differential regulation of the same gene set modulated in the normal breast, in human breast tumors following pregnancy. Gene expression was measured by real-time PCR on tumor regions isolated by laser capture microdissection from paraffin sections. Immunohistochemistry was performed on tissue microarrays (TMA) for protein expression. Hierarchical clustering was performed using the average linkage method to determine coordinate expression of sets of genes. We find that breast cancers detected within 10 years following pregnancy display a different gene expression pattern than those detected in nulliparous breast cancer patients. The gene expression difference is mainly attributable to a triple negative (TNBC) subgroup found to be more frequent in PABCs up to 10 years following a pregnancy. We also show that protein and mRNA expression levels correlate in half of the proteins tested by TMA. Despite the fact that this is a small study of 53 patients, we identified a gene expression signature that is differentially expressed in pregnancy-associated TNBC.

Breast lumps in pregnant women

Breast lumps detected during pregnancy are generally benign and reflect fibroadenoma, lactating adenoma, cysts, infarction of the breast or galactocele. Although rare, the possibility of breast cancer must also be considered to avoid any delays in diagnosis. After patient questioning and clinical examination, the first imaging modality to use is ultrasound. No further assessment is called for if lesions are categorized as BI-RADS 2 and no suspicious clinical signs are observed. Depending on the clinical setting, lesions classified BI-RADS 3 require monitoring and mammographic assessment (which can be helpful in diagnosing cancer and incurs no risk to the embryo or fetus). If the clinical signs are unclear and/or the lesion(s) are categorized as ≥ BI-RADS 4a, then mammography and often biopsy should be performed. Strict BI-RADS scoring (American College of Radiology) should be applied, bearing in mind that benign lesions can appear suspicious during pregnancy, and some cancers can exhibit what seem to be reassuring characteristics.