Breast Cancer and Pregnancy

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.

Biology, staging, and treatment of breast cancer during pregnancy: reassessing the evidences

Breast cancer is one of the most frequently diagnosed malignancies during pregnancy. Here, we review the management of women with breast cancer during pregnancy (BCP), focusing on biology, diagnosis and staging, local and systemic treatments, obstetric care and long-term follow-up of children with prenatal exposure to anticancer treatments.

Stage at diagnosis and mortality in women with pregnancy-associated breast cancer (PABC)

Converging evidence indicates that women with pregnancy-associated breast cancer (PABC) have increased mortality compared to women with breast cancer not diagnosed near pregnancy (non-PABC). Our aim was to investigate if the stage distribution differs between PABC and non-PABC and if stage at diagnosis can explain the poorer prognosis observed among women with PABC. We identified 3,282 breast cancers in women aged 15-44 years at diagnosis for whom staging data (tumor size, nodal involvement, metastasis) were available in the Swedish Cancer Register between 2002 and 2009. Information on reproductive history and vital status was obtained from the Multi-Generation Register and the Cause of Death Register. PABC was defined as breast cancers diagnosed during pregnancy and up to 2 years after delivery (n = 317). Non-PABC was defined as cases diagnosed before pregnancy or more than 2 years postpartum. Stage distributions were compared between PABC and non-PABC, and mortality rates were modeled using Cox regression. Compared to women with non-PABC, the mortality was almost 50 % higher in women with PABC [unadjusted hazard ratio (HR) 1.47 (95 % CI 1.04-2.08)], a difference which was reduced after adjustment for age and calendar year of diagnosis [HR 1.27 (95 % CI 0.88-1.83)]. Although advanced stage of breast cancer at diagnosis was more common among PABC than among non-PABC, further adjustment for stage only slightly reduced the HR [1.22 (95 % CI 0.84-1.78)]. The difference in mortality between PABC and non-PABC was more pronounced among women above 35 years and among women with PABC diagnosed within 1 year postpartum. Age, rather than stage at diagnosis, appears to act as the principal driver of the increased mortality observed in women with PABC. However, these findings do not preclude an untoward influence on mortality by pregnancy-associated factors affecting tumor aggressiveness and progression.

Increased mortality in women with breast cancer detected during pregnancy and different periods postpartum

BACKGROUND

Because of a continued trend toward postponed childbearing, the incidence of pregnancy-associated breast cancer (PABC) is likely to increase. This study investigated the mortality in women with PABC in relation to when the tumor was detected (during pregnancy, different postpartum periods) and by time since diagnosis, compared with women with non-PABC.

METHODS

A population-based cohort study of 15,721 Swedish women diagnosed with breast cancer between ages 15 to 44 years, of whom 1,110 (7%) had a PABC (diagnosed during or within two years after pregnancy). Information on outcome and potential confounders was obtained from population-based health registers. Mortality rates and HRs with 95% CIs were estimated.

RESULTS

Women with PABC had higher mortality compared with women with non-PABC diagnosed at the same age and calendar period. Among women with PABC, 46% died within 15 years after diagnosis, whereas 34% died among non-PABC patients. The mortality in both groups peaked at around two years after diagnosis, with the highest peak occurring in women diagnosed 4 to 6 months after delivery (HR = 3.8, 95% CI: 2.4-5.9). An increased mortality among women with PABC remained until 10 years after diagnosis.

CONCLUSIONS

Women with PABC had a poorer prognosis compared with women with breast cancer and no recent birth. The mortality increase was most pronounced in the subgroup of women diagnosed shortly after delivery.

IMPACT

An increased awareness among clinicians may help reduce the mortality in women with PABC, for example, by avoiding undue delays in diagnosis and treatment.

Breast-feeding after breast cancer in childbearing women

According to the American Cancer Society in 2007, about 178,000 women are diagnosed with breast cancer each year in the United States. Of these, 25% have tumors in their childbearing years and may desire future opportunities for pregnancy and lactation. Although there is a multitude of options related to preserving fertility, little is known about the residual effects of breast cancer treatment and the ability to breast-feed afterward. This article describes the epidemiological relationship between breast cancer and pregnancy and lactation. Basic types of treatment for breast cancer including surgery, chemotherapy, and radiation are reviewed. Practical information on how to support breast-feeding after breast cancer is included.

Human chorionic gonadotropin as an angiogenic factor in breast cancer during pregnancy

Breast cancer associated with pregnancy is defined as the one in which the diagnosis is made in a pregnancy or within one year of delivery. Breast cancer is the second most common malignancy during pregnancy and it is generally considered to have a worse prognosis than the one that is not associated with pregnancy. The average patient is between 32 and 38 years of age. Steroid hormone receptor-positive cell populations comprise 80% of breast cancers, however, estrogen receptor levels in pregnancy-associated tumors are often low or absent. Extensive laboratory data suggest that angiogenesis plays an essential role in breast cancer development, invasion, and metastasis. One of the most powerful stimulatory factors, vascular endothelial growth factor (VEGF), functions in autocrine/paracrine pathways. Current research, generally has validated the poor prognosis and early relapse that are associated with increasing microvessel density, which is related to VEGF expression in tumoral cells. During pregnancy, human chorionic gonadotropin (hCG) induces neovascularization in various tissues, one of them being the placenta. Its receptors have been detected in epithelial cells in breast carcinoma tissue, and breast cancer cell lines. According to this premise the hCG normally produced during pregnancy could induce the synthesis of VEGF and by this means stimulate the development and metastatic potential of breast cancer cells in the pregnancy period. Thus, research involving hCG and VEGF would help us understand the physiopathology of breast cancer during pregnancy, as well as provide us with probable prognostic tools.