Effect of age at first childbirth on risk of developing specific histologic subtype of breast cancer

Survival Outcomes in Invasive Lobular Carcinoma Compared to Oestrogen Receptor-Positive Invasive Ductal Carcinoma

Invasive lobular breast cancer (ILC) accounts for 10-15% of breast cancers and has distinct characteristics compared with the more common invasive ductal carcinoma (IDC). Studies have shown that ILC may be less sensitive to chemotherapy than IDC, with lower rates of complete pathological response after neo-adjuvant chemotherapy, but it is not clear how this affects long-term survival. Patients at Guy's and St Thomas' NHS Foundation Trust between 1975 and 2016 diagnosed with ER+ IDC or ER+ ILC were eligible for inclusion. Kaplan-Meier plots and Cox proportional-hazards regression models were used for analysis. There was no difference in overall survival comparing ER+ ILC to ER+ IDC (OR: 0.94, 95% CI: 0.83, 1.04) with a median follow-up time of 8.3 years compared to 8.4 years in IDC. However, ER+HER2- ILC had worse survival compared to ER+HER2- IDC in those that received chemotherapy (OR: 1.46, 95% CI: 1.06, 2.01). Here, median follow-up time was 7.0 years in ILC compared to 8.1 years in IDC. These results indicate worse overall survival after chemotherapy (neo-adjuvant and adjuvant) in ILC compared to ER+HER2- IDC even when correcting for tumour grade, age, size, and nodal involvement, but validation is needed in a larger study population.

Lobular breast cancer: incidence and genetic and non-genetic risk factors

While most invasive breast cancers consist of carcinomas of the ductal type, about 10% are invasive lobular carcinomas. Invasive lobular and ductal carcinomas differ with respect to risk factors. Invasive lobular carcinoma is more strongly associated with exposure to female hormones, and therefore its incidence is more subject to variation. This is illustrated by US figures during the 1987 to 2004 period: after 12 years of increases, breast cancer incidence declined steadily from 1999 to 2004, reflecting among other causes the decreasing use of menopausal hormone therapy, and these variations were stronger for invasive lobular than for invasive ductal carcinoma. Similarly, invasive lobular carcinoma is more strongly associated with early menarche, late menopause and late age at first birth. As for genetic risk factors, four high-penetrance genes are tested in clinical practice when genetic susceptibility to breast cancer is suspected, BRCA1, BRCA2, TP53 and CDH1. Germline mutations in BRCA1 and TP53 are predominantly associated with invasive ductal carcinoma, while BRCA2 mutations are associated with both ductal and lobular cancers. CDH1, the gene coding for the E-cadherin adhesion protein, is of special interest as mutations are associated with invasive lobular carcinoma, but never with ductal carcinoma. It was initially known as the main susceptibility gene for gastric cancer of the diffuse type, but the excess of breast cancers of the lobular type in CDH1 families led researchers to identify it also as a susceptibility gene for invasive lobular carcinoma. The risk of invasive lobular carcinoma is high in female mutation carriers, as about 50% are expected to develop the disease. Carriers must therefore undergo intensive breast cancer screening, with, for example, yearly magnetic resonance imaging and mammogram starting at age 30 years.

Dual effect of short interval between first and second birth on ductal breast cancer risk in Finland

OBJECTIVE

A short interval between the first and second birth was associated with an increased risk of advanced ductal breast cancer among women with 5+ childbirths in our previous study. We now evaluated the significance of this risk factor and its relation to the age at first birth among mothers with 2-4 children.

METHODS

The cohort of 190,949 Finnish women with 2-4 children comprised 3,834 women with ductal breast cancer diagnosed before 2009. Conditional logistic regression for case-control design nested within the cohort was used to estimate proportional hazard ratios (HR) associated with the birth interval. Controls were matched for age and number of children. Age at the first birth and the interval from the last birth to cancer were co-variables.

RESULTS

Among women with the first birth <30 years, the HR of advanced ductal breast cancer at 50+ years for a short (<1.5 years) versus long (>3 years) interval between the first and second birth was 0.48 (95% Confidence Interval 0.33-0.70). Among women with the first birth at 30+ years, the HR of this cancer type diagnosed before the age of 50 years for a short versus long interval between the first and second birth was 5.83 (95% CI 2.30-14.8).

CONCLUSION

The interval between first and second birth strongly influences the risk of ductal breast cancer. Because second pregnancy soon after the first one decreased the risk of ductal breast cancer in young primiparas but increased the risk in older primiparas, it is likely that in such circumstances second pregnancy continues the actions initiated by the first pregnancy/breast-feeding.

Reproductive factors and specific histological types of breast cancer: prospective study and meta-analysis

Little is known about how reproductive factors affect the risk of breast cancers of different histology. In an analysis of prospective data on 1.2 million middle-aged UK women, we used proportional hazards models to estimate the relative risks of six histological types in relation to menarche, childbearing and menopause. During 8.7 million person-years of follow-up, 17 923 ductal, 3332 lobular, 1062 tubular, 944 mixed ductal lobular, 330 mucinous and 117 medullary cancers were diagnosed. The effect of both age at menarche and age at first birth was greatest for lobular tumours; relative risks per 5-year increase in age at menarche for ductal, lobular, and tubular cancers were 0.93 (0.87-0.99), 0.65 (0.56-0.76), and 0.75 (0.57-0.98), respectively (P-value for heterogeneity=0.0001); and the relative risks per 5-year increase in age at first birth were 1.10 (1.07-1.12), 1.23 (1.17-1.29), and 1.13 (1.03-1.23), respectively (P-value for heterogeneity=0.0006). Increasing parity reduced the risk of each tumour type, except medullary cancers, but the reduction in risk was greater for mucinous cancers than for any other subtype considered (P<0.05 for comparison with each other subtype in turn). The effect of menopause did not vary significantly by tumour histology. Meta-analysis of published results on the effects of age at menarche and age at first birth on ductal and lobular cancers were in keeping with our findings.

Established breast cancer risk factors by clinically important tumour characteristics

Breast cancer is a morphologically and clinically heterogeneous disease; however, it is less clear how risk factors relate to tumour features. We evaluated risk factors by tumour characteristics (histopathologic type, grade, size, and nodal status) in a population-based case-control of 2386 breast cancers and 2502 controls in Poland. Use of a novel extension of the polytomous logistic regression permitted simultaneous modelling of multiple tumour characteristics. Late age at first full-term birth was associated with increased risk of large (> 2 cm) tumours (odds ratios (95% confidence intervals) 1.19 (1.07-1.33) for a 5-year increase in age), but not smaller tumours (P for heterogeneity adjusting for other tumour features (Phet) = 0.007). On the other hand, multiparity was associated with reduced risk for small tumours (0.76 (0.68-0.86) per additional birth; Phet = 0.004). Consideration of all tumour characteristics simultaneously revealed that current or recent use of combined hormone replacement therapy was associated with risk of small (2.29 (1.66-3.15)) and grade 1 (3.36 (2.22-5.08)) tumours (Phet = 0.05 for size and 0.0008 for grade 1 vs 3), rather than specific histopathologic types (Phet = 0.63 for ductal vs lobular). Finally, elevated body mass index was associated with larger tumour size among both pre- and postmenopausal women (Phet = 0.05 and 0.0001, respectively). None of these relationships were explained by hormone receptor status of the tumours. In conclusion, these data support distinctive risk factor relationships by tumour characteristics of prognostic relevance. These findings might be useful in developing targeted prevention efforts.

Comparison of Age-Specific Incidence Rate Patterns for Different Histopathologic Types of Breast Carcinoma

Objective: The age-specific incidence rate curve for breast carcinoma overall increases rapidly until age 50 years, and then continues to increase at a slower rate for older women. In this analysis, our objective was to compare age-specific incidence rate patterns for different morphologic types of breast carcinoma. Materials and methods: We analyzed age-specific incidence rate curves by histopathologic subclassification using records from 11 standard National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) registries, diagnosed during the years 1992 to 1999. Data were examined by age &lt;50 and ≥50 years to simulate menopause. Results: Age-specific incidence rate curves showed three dominant patterns: (1) Rates for infiltrating duct carcinoma of no special type (duct NST), tubular, and lobular carcinomas increased rapidly until age 50 years then rose more slowly. (2) Rates for medullary and inflammatory breast carcinomas increased rapidly until age 50 years then failed to increase. (3) Rates for papillary and mucinous carcinomas increased steadily at all ages. Rate patterns varied by estrogen receptor expression but were unaffected by SEER registry, race, nodal status, or grade. Conclusion: Age-specific incidence rates for breast carcinomas differed by histopathologic type. Rates that failed to increase after 50 years suggested that menopause had greater impact on medullary and inflammatory carcinomas than on duct NST, tubular, and lobular carcinomas. Menopause did not seem to have any effect on papillary or mucinous carcinomas as evidenced by steadily rising rates at all ages. Future etiologic and/or prevention studies should consider the impact of age-specific risk factors and/or exposures on different histopathologic types of breast carcinomas.

Reproductive risk factors for breast cancer by receptor status, histology, laterality and location

It is well established that a woman's reproductive history influences her risk of breast cancer. We examined whether the effect of reproductive history was similar for different sub-types of breast cancer. The study was based on a population-based cohort of 1.5 million Danish women born between 1935 and 1978, with individual information on births. Between 1978 and 1994, 10,790 incident cases of breast cancer were identified in a nationwide cancer registry, including detailed information on receptor status, histology, laterality and location of the tumour. Overall, the incidence of breast cancer was 13% lower in parous compared with nulliparous women. This reduction was significantly stronger for mucinous than for ductal carcinomas and for tumours located centrally than for those non-central in the breast. Overall, the incidence in parous women increased by 10% by each 5-year postponement of their first birth. For the incidence of lobular carcinomas this increase was significantly stronger, and for mucinous carcinomas it tended to be stronger than for ductal carcinomas. For the incidence of centrally located tumours the increase was stronger than for non-centrally located tumours. On average, there was a 10% decrease in breast-cancer risk by each additional birth. This decrease was seen in most sub-types, but not for lobular carcinomas of for centrally located tumours. According to our findings, lobular and mucinous carcinomas and centrally located tumours may have risk-factor profiles that differ from other types of breast cancer.

The pathology of familial breast cancer: Morphological aspects

A small proportion of breast cancers are due to a heritable predisposition. Recently, two predisposition genes, BRCA1 and BRCA2, have been identified and cloned. The morphological features of tumours from patients harbouring mutations in the BRCA1 and BRCA2 genes differ from each other and from sporadic breast cancers. Both are of higher grade than are sporadic cases. An excess of medullary/atypical medullary carcinoma has been reported in patients with BRCA1 mutations. Multifactorial analysis, however, shows that the only features independently associated with BRCA1 mutations are a high mitotic count, pushing tumour margins and a lymphocytic infiltrate. For BRCA2 mutation, an association with tubular/lobular carcinoma has been suggested, but not substantiated in a larger Breast Cancer Linkage Consortium study. In multifactorial analysis, the independent features were a lack of tubule formation and pushing tumour margins only. The morphological analysis has implications for clinical management of patients.

A review on family history of breast cancer: screening and counseling proposals for women with familial (non-hereditary) breast cancer

With the aim to specify screening recommendations for women with familial (non-hereditary) breast cancer (FBC) we analysed 59 studies using quantitative methods of pooling. The pooled relative risk (RR) and cumulative probability were used to estimate breast cancer risk. The RRs for women with a family history of breast cancer in a first-degree relative was 2.03 (95% CI 1.09-2.22). The highest RR is observed for women with a family history and atypical hyperplasia in their breast biopsy specimen (RR = 10.87, 95% CI 6.05-19.69). A high cumulative probability before the age of 50 was only found for women with a combination of two risk factors: a family history and atypical hyperplasia, namely 19% (95% CI 11-33%). The cumulative probabilities of women aged 50 to 70 years who have a family history were between 11% (95% CI 9-13%, a family history in combination with age at first birth before 22 years) and 53% (95% CI 35-75%, a family history in combination with atypical hyperplasia). These high risks suggest that women over 50 years of age who have a family history of FBC have to be actively encouraged to participate in a screening program consisting of a biannual palpation by a specialist, an annual mammogram and a monthly self-control. Yearly screening is recommended for women under 50 years of age who have a family history and atypical hyperplasia. These recommendations remain valid until the effectiveness of such screening programs is assessed.

Relationship between breast histopathology and family history of breast cancer

BACKGROUND

The relationship between breast cancer histology and a number of epidemiologic risk factors associated with breast cancer was examined in 4071 histologically confirmed breast cancer cases aged 20 to 54 years from the Cancer and Steroid Hormone Study.

METHODS

The distribution of risk factors, which included a family history of breast cancer, age at onset of breast cancer, laterality, race, age at menarche, age at menopause, history of benign breast disease, parity, number of livebirths and number of stillbirths, and age at first childbirth, were examined by histologic subgroup. To determine whether histology is associated with familial risk of breast cancer, a Cox proportional hazards model was used, modeling time to onset of breast cancer among mothers and sisters.

RESULTS

Cases with medullary carcinoma were found to be significantly younger than cases with other tumor types in these data. In addition, medullary carcinoma was reported more frequently among black cases than among white cases. Cases with lobular carcinoma in situ were significantly more likely to have a mother and/or sister affected with breast cancer than cases with other tumor types and were also more likely to be bilateral, although few of these cases were both bilateral and reported a family history of breast cancer. The highest reported rates of benign breast disease occurred in cases with carcinoma in situ (both ductal and lobular) and tubular carcinoma. The remaining risk factors showed no association with histology.

CONCLUSIONS

The current study clarifies the extent and nature of the relationship between breast cancer histology and epidemiologic risk factors including a family history of breast cancer.

Histologic types of breast carcinoma in relation to international variation and breast cancer risk factors. WHO Collaborative Study of Neoplasia and Steroid Contraceptives

Associations between breast cancer risk factors and histologic types of invasive breast carcinoma were studied in 2,728 patients. Lobular and tubular carcinomas occurred with increased relative frequency in most high-risk groups. The proportion of these types increased with age to a maximum at 45-49 years and decreased in the following decade. Significantly increased proportions of lobular and tubular carcinomas were also associated with high-risk countries, prior benign breast biopsy, bilateral breast cancer, concurrent mammary dysplasia, high age at first live birth, never-pregnant patients compared to those with a first live birth before age 20, private pay status, and length of education. Nonsignificant increases were associated with family history of breast cancer, less than 5 live births, less than 25 months total of breast feeding, use of oral contraceptives or IUD, and high occupational class. As a general trend, the higher the overall relative risk, the higher the proportion of lobular and tubular carcinomas. The occurrence of other histologic types also increased with increased breast cancer risk, but to a smaller degree than for lobular/tubular carcinomas. It is suggested that all hormonally related, socio-economic and geographic risk factors exert their effect by selectively increasing number of lobular cells at risk. Family history of breast carcinoma and age over 49 years did not follow the general trend parallel increases in the proportion of lobular/tubular carcinomas and breast cancer risk, and may operate through other mechanisms.

Risk of breast cancer in relation to reproductive factors in Denmark

The effect of reproductive factors on breast cancer risk was evaluated in a population-based case-control study, including 1,486 breast cancer cases diagnosed over a one-year period in Denmark. They were identified from the files of the nationwide trial of the Danish Breast Cancer Co-operative group and the Danish Cancer Registry. The control group was an age-stratified random sample of 1,336 women from the general population. Data on risk factors were collected by self-administered (mailed) questionnaires. Significantly increased relative risks (RR) were associated with never being pregnant (RR = 1.47), an early terminated first pregnancy (RR = 1.43), and having a natural menopause after the age of 54 (RR = 1.67). Trends of decreasing risk were observed by increasing parity and age at menarche. These findings were independent of age at first full-term pregnancy which overall was not related to breast cancer risk, though a weak association appeared in women less than 50 years at diagnosis. The study confirmed that pregnancies must continue to term to offer protection against breast cancer.

Projected changes in breast cancer incidence due to the trend toward delayed childbearing

Because there has been a recent trend toward delay of childbearing in the United States, women in the birth cohort of 1945-49 will have an estimated 5 per cent greater incidence of breast cancer, and those in the cohort of 1950-54 an estimated 9 per cent greater incidence compared with the cohort of 1935-39, which had the distribution of age at first birth most favorable for breast cancer risk.

Factors associated with the risk of second primary breast cancer: an analysis of data from the Connecticut Tumor Registry

To examine further the epidemiology of contralateral primary breast cancer, a case-control analysis, utilizing information available from the Connecticut Tumor Registry, was conducted. Recent cases of second primary breast cancer were compared to control women who had survived a first breast cancer but had not developed a second. Three hundred and thirty eight incident cases of contralateral breast cancer diagnosed between 1979 and 1982 were identified and compared with an equal number of randomly selected controls and 336 controls frequency matched to the cases on the basis of age at initial cancer diagnosis and the calendar time elapsing since that diagnosis. Risk of second primary breast cancer was found to be significantly elevated among women whose initial cancer was lobular carcinoma and during the first year following diagnosis of the initial primary. Additionally, for women initially treated with radiotherapy, risk of a contralateral primary increased for 10-14 years following treatment, after which it declined. Among young women, having never married was protective whereas the opposite was found among older women. These findings and the methods used are discussed in the context of the epidemiology of both contralateral and initial breast primaries.

Genetics, biomarkers, and control of breast cancer: a review

More has been written about the epidemiology of breast cancer than possibly any other form of cancer affecting mankind. However, in the face of this intense interest, only a paucity of attention has been given to the role of genetics in its etiology. This review represents an attempt by the investigators to provide a comprehensive coverage of hereditary breast cancer. Included are pertinent endogeneous and exogeneous risk factors, which in certain circumstances, may significantly influence the role of primary genetic factors. Hereditary breast cancer is heterogeneous. When discussing the subject, therefore, one must be precise relevant to the particular heterogeneous form of concern, based on differing tumor associations. It is probably not appropriate to discuss "hereditary breast cancer" without qualification of the specific hereditary breast cancer syndrome of concern; i.e., the SBLA syndrome, breast/ovarian cancer syndrome, and others. This reasoning also applies to attempts at linking biomarkers to hereditary breast cancer. Finally, in addition to ongoing discussions on the cardinal principles that associate with hereditary forms of breast cancer, its frequency, and new developments in biomarkers, we have provided surveillance/management programs that embrace those facets of the natural history of this disease.

Histopathological features and their association with steroid receptors in women with breast cancer in Fukuoka, Japan

In Fukuoka, Japan, infiltrating duct carcinoma predominated among 213 breast cancer cases, age 45 to 74. Lobular and medullary carcinomas were infrequent. About thirty three percent of the women had marked productive fibrosis, based on the UICC code type. Both rough margin and productive fibrosis of the cancer increased with age of the patients. On the contrary, most of accompanying hyperplastic lesions decreased with age. The difference was significant for cystic formation between 10-year age groups of 45-54 and 55-64 (chi 2 = 6.61, p less than 0.02). Hormone receptors of 115 of the cases were independently measured and characterized according to histologic patterns manifesting host reaction (stromal cell infiltration and lymph node histiocytosis). Positive estrogen receptors were more frequent among ductal carcinomas with slight or no cellular reaction than those with extensive cellular reaction. The same pattern was also present for progesterone and androgen receptors. The extent of sinus histiocytosis in lymph nodes without metastasis was also inversely correlated with the presence of these hormone receptors. The correlation was significant for androgen receptor (chi 2 = 5.31, p less than 0.05). Positive estrogen receptor was more common among ductal carcinomas with prominent fibrosis than among those with minimal fibrosis.