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1.
Breast cancer rarely occurs in women below the age of 35 years. Data from various sources indicate that diagnosis at such an age is associated with a dire prognosis mainly because of a more aggressive presentation. Although the effect of chemotherapy for premenopausal patients is substantial, recent evidence on 2233 patients suggested that very young women with endocrine-responsive tumors had a statistically significantly higher risk of relapse than older premenopausal patients with such tumors. In contrast, results for younger and older premenopausal patients were similar if their tumors were classified as endocrine nonresponsive. Information from studies on 7631 patients who were treated with chemotherapy alone in trials of three major U.S. cooperative groups showed a similar interaction between the effect of age and steroid hormone receptor status of the primary tumor. Better treatments for very young patients are required and may involve ovarian function suppression in addition to other endocrine agents in patients with endocrine responsive tumors and a more precise investigation of chemotherapy and its timing, duration, and intensity in those with endocrine nonresponsive tumors. Very young women with this disease are faced with personal, family, professional, and quality-of-life issues, which further complicate the phase of treatment decision making. The development of more effective therapies for younger patients requires tailored treatment investigations and cannot rely on information predominantly contributed from older premenopausal women.  相似文献   

2.
Breast cancer in adolescents and young women   总被引:2,自引:0,他引:2  
Breast cancer is very rare in adolescents and very young women. Less than 1% of all breast cancer cases occur before the age of 30 years (Natl Cancer Inst Monogr 16 (1994) 69). Invasive breast cancer occurring in women before the age of 35 years has a more aggressive biological behaviour and is associated with a worse prognosis than in older premenopausal women. Breast cancers in these young women are more frequently poorly differentiated, oestrogen-receptor (ER)-negative, have lymphovascular invasion and high proliferating fractions. Breast-conserving surgery in women <35 years old is associated with a higher risk of local recurrence than in older women. All young women should be considered at moderate-high risk by virtue of their age alone and offered adjuvant therapy. The long-term toxicity of adjuvant therapies is a particular concern when treating these women. The implications of possible fertility impairment and premature menopause require consideration when discussing adjuvant chemotherapy and endocrine therapy. Adolescents and young women are particularly vulnerable to emotional distress and psychosocial problems and should be provided with appropriate support. Young women who are at a potential high-risk of developing breast cancer such as those with germline mutations of BRCA1, BRCA2, TP53, PTEN or who have previously received mantle irradiation for Hodgkin's disease need close follow-up and are candidates for screening from a young age.  相似文献   

3.
The effect of age on breast cancer survival is still a matter of controversy. Breast cancer in young women is thought to be more aggressive and to have worse prognosis but results from clinical research have been neither consistent nor definitive. In this study, we have assessed the impact of young age at diagnosis on tumor characteristics, treatment and survival of breast cancer. The study included 82 very young (< or = 35 years), 790 young (36-49), and 2125 older (50-69) women recorded between 1990 and 2001 at the Geneva Cancer Registry. Very young and young patients had more often stage II cancers (P = 0.009), poorly differentiated (P < 0.001) and estrogen receptor negative (P < 0.001) tumors. They were also more likely to receive chemotherapy (P < 0.001) and less likely to receive hormonal therapy (P < 0.001). Specific five-year survival was not different in the three groups (91%, 90%, and 89% for very young, young and older, respectively). When adjusting for all prognostic variables, age was not significantly related to mortality from breast cancer with a hazard ratio of 0.8 (95% CI: 0.3-2.0) for very young and 1.1 (95% CI: 0.8-1.4) for young patients compared to older women. Tumor stage, differentiation, estrogen receptor status, surgery, and radiotherapy were all independent determinants of breast cancer prognosis. We conclude that age is not an independent prognostic factor when accounting for breast tumor characteristics and treatment.  相似文献   

4.
OBJECTIVE: The objective of this retrospective study was to discuss the epidemioclinical criteria, the therapeutic results and the prognostic factors of breast cancer in young women throughout a comparative study of 72 young patients aged less than 35 years and a second group of older premenopausal patients aged between 36 and 50 years. PATIENTS AND METHODS: We reviewed the epidemioclinical records of all the patients. Non-metastatic and operable patients were treated with surgery (conservative or radical) followed by an adjuvant treatment (chemotherapy, radiotherapy, endocrine therapy) indicated according to the prognostic factors. Locally advanced or metastatic tumors were treated with chemotherapy. Overall survival was calculated according to the Kaplan-Meier method. The comparison of survival curves was performed according to log-rank test.The multivariate analysis was performed according to the Cox model. RESULTS: The mean age was of 31.5 years. T2N1, node positive (N+), high grade (SBRII and III) and endocrine non-responsive tumors were the most frequent. There was no difference with the second group of older patients regarding the risk factors and the clinical criteria but mammography was more sensitive in the second group. The 5 years overall survival of young patients was of 57% and pejorative prognostic factors in univariate analysis were: tumor size, N+ and endocrine non-responsiveness. There were not any significant prognostic factors at the multivariate analysis. Young age less than 35 years was not a prognostic factor influencing overall survival in the totality of patients or in the different sub-groups according to the other prognostic factors. CONCLUSION: Clinical presentation and outcome of breast cancer in our young patients aged under 35 years seems not to be different from that in older patients. The conclusions of the different authors are controversial but the majority has reported more advanced tumors with worse prognostic than those of older patients.  相似文献   

5.
BACKGROUND: Breast cancer rarely occurs in young women. Our knowledge about disease presentation, prognosis and treatment effects are largely dependent upon older series. MATERIALS AND METHODS: We evaluated biological features and stage at presentation for 1427 consecutive premenopausal patients aged < or = 50 years with first diagnosis of invasive breast cancer referred to surgery at the European Institute of Oncology from April 1997 to August 2000. A total of 185 patients (13%) were aged < 35 years ('very young') and 1242 (87%) were aged 35-50 years ('less young'). The expression of estrogen receptors (ER), progesterone receptors (PgR), presence of vascular invasion (VI), grading (G), expression of Ki-67, HER2/neu overexpression, pathological stage according to TNM staging system (pTNM), pathological tumor size and number of axillary lymph node involvement were evaluated. RESULTS: Compared with less young patients, the very young patient group had a higher percentage of tumors classified as ER negative (P < 0.001), PgR negative (P = 0.001), higher expression of Ki-67 > or = 20% of cells stained; 62.2% versus 53%, (P < 0.001), vascular or lymphatic invasion (48.6% versus 37.3%, P = 0.006), and pathological grade 3 (P < 0.0001). There was no difference between the two groups for pT, pathological tumor size (pN) and number of positive lymph nodes. CONCLUSIONS: We conclude that compared with less young premenopausal patients, very young women have a greater chance of having an endocrine-unresponsive tumor, and are more likely to present with a higher grade, more extensively proliferating and vessel invading disease. Pathological tumor size, nodal status and number of positive axillary lymph-nodes have a similar distribution among the younger and the older cohorts, thus not supporting previous data indicating more advanced disease in younger patients at diagnosis of operable disease.  相似文献   

6.
BACKGROUND: Among middle-aged and older women with early breast carcinoma, breast-conserving therapy (BCT) has been shown to have an effect on survival that is similar to that of modified radical mastectomy (RM). Nonetheless, it remains to be established whether BCT also is the optimal treatment option for early breast carcinoma in young women, because these women generally have more aggressive disease and a higher frequency of local recurrence compared with older women. METHODS: We investigated a cohort of 9285 premenopausal women with primary breast carcinoma who were age < 50 years at diagnosis. These women were identified from a population-based Danish breast carcinoma database containing detailed information on patient and tumor characteristics, predetermined treatment regimens, and survival. RESULTS: In total, 7165 patients (77.2%) were treated with RM, and 2120 patients (22.8%) were treated with BCT. We calculated the relative risk of death within the first 10 years after diagnosis according to surgical treatment and age, both before and after adjustment for known prognostic factors. No increased risk of death was observed among women who received BCT compared with women who underwent RM, regardless of age at diagnosis (< 35 years, 35-39 years, 40-44 years, or 45-49 years), despite the increased risk of local recurrence among young women. Restricting the analysis to women with small tumors (size < 2 cm) yielded similar results. CONCLUSIONS: Despite having a higher rate of local recurrence, young women with breast carcinoma who receive BCT are similar to young women treated with RM in terms of survival.  相似文献   

7.
Breast cancers among very young premenopausal women (United States)   总被引:5,自引:0,他引:5  
Objective: To assess risk factors for breast cancer among very young compared to older premenopausal women. Methods: Between 1990 and 1992 a population-based case–control study conducted in Atlanta, GA, Seattle/Puget Sound, WA, and central NJ interviewed 3307 premenopausal women aged 20–54 years. Logistic regression models estimated adjusted relative risks (RR) and 95% confidence intervals (CI) for each of three 10-year age groups. Results: Among the youngest age group (<35 years, n = 545), significant predictors of risk included African-American race (RR = 2.66; 95% CI 1.4–4.9) and recent use of oral contraceptives (RR = 2.26; 95% CI 1.4–3.6). Although these relationships were strongest for estrogen receptor-negative (ER–) tumors (RRs of 3.30 for race and 3.56 for recent oral contraceptive use), these associations were also apparent for young women with ER+ tumors. Delayed childbearing was a risk factor for ER+ tumors among the older premenopausal women (p trend < 0.01), but not for women <35 years in whom early childbearing was associated with an increased risk, reflecting a short-term increase in risk immediately following a birth. Family history of early-onset breast cancer was more strongly associated with risk among women <35 years (RR = 3.22) than those 45–54 years (RR = 1.51). Risk factors for premenopausal breast cancer not significantly modified by age at diagnosis included early age at menarche, low body mass index, and heavy alcohol consumption. Conclusion: These findings suggest the possibility that women who develop breast cancers at very young ages may be etiologically as well as clinically distinct.  相似文献   

8.
Triple-negative breast cancer (TNBC) is diagnosed more frequently in younger and premenopausal women and is highly prevalent in African American women. TNBC is a term derived from tumors that are characterized by the absence of ER, PgR, and HER2. So patients with TNBC do not benefit from hormonal or trastuzumab-based therapies. TNBCs are biologically aggressive, although some reports suggest that they respond to chemotherapy better than other types of breast cancer, prognosis remains poor. This is due to: shortened disease-free interval in the adjuvant and neoadjuvant setting and a more aggressive course in the metastatic setting.KEYWORDS : Breast cancer, triple-negative, HER2  相似文献   

9.
目的:探讨患者年龄及不同蒽环联合紫杉类化疗方案对化疗诱导停经的影响,为临床合理用药提供依据.方法:前瞻性研究绝经前乳腺癌患者接受化疗后月经变化情况,比较不同年龄段及使用不同化疗方案的患者月经状态变化的差异.结果:144例患者,≤40岁患者化疗诱导停经和长期闭经的发生率均显著低于>40岁的患者(P<0.05),并且该组发生CIA后月经恢复率较高( P<0.05).同时还发现>40岁患者中砝码新联合泰索蒂方案诱导长期闭经率显著高于其他三组(P=0.016).结论:年龄是化疗诱导停经的重要因素,≤40岁患者月经受化疗影响较小,停经多为可逆性.>40岁患者使用不同的蒽环联合多西紫杉醇类化疗药物对月经状态存在显著性的影响.  相似文献   

10.
目的:探讨患者年龄及不同蒽环联合紫杉类化疗方案对化疗诱导停经的影响,为临床合理用药提供依据。方法:前瞻性研究绝经前乳腺癌患者接受化疗后月经变化情况,比较不同年龄段及使用不同化疗方案的患者月经状态变化的差异。结果:144例患者,≤40岁患者化疗诱导停经和长期闭经的发生率均显著低于〉40岁的患者(P〈0.05),并且该组发生CIA后月经恢复率较高(P〈0.05)。同时还发现〉40岁患者中砝码新联合泰索蒂方案诱导长期闭经率显著高于其他三组(P=0.016)。结论:年龄是化疗诱导停经的重要因素,≤40岁患者月经受化疗影响较小,停经多为可逆性。〉40岁患者使用不同的蒽环联合多西紫杉醇类化疗药物对月经状态存在显著性的影响。  相似文献   

11.
PURPOSE: Young women who undergo chemotherapy for breast cancer face serious consequences to their reproductive health. Research in this area has previously focused on men, or on childhood cancer survivors. We sought to explore self-report of reproductive health counseling in young women undergoing chemotherapy for breast cancer. PATIENTS AND METHODS: A total of 166 premenopausal women aged < or = 50 years were recruited from oncology offices in academic and private practices in four northeastern states, as part of a randomized controlled clinical trial aimed at stress reduction. Women were asked a variety of questions regarding diagnosis and treatment, including whether they received any counseling regarding early menopause and fertility issues. RESULTS: Sixty-eight percent and 34% of women reported recalling a discussion with a physician regarding early menopause or fertility, respectively. In multivariate analysis, hormonal therapy and early stage of disease were associated with significantly increased odds of recall of a discussion regarding menopause. Difficulty communicating with medical team was associated with increased odds of recalling a discussion regarding fertility, whereas older age and anxiety in medical situations were associated with decreased odds. CONCLUSION: Many women fail to recall discussions regarding the reproductive health impact of chemotherapy. Demographic, psychological, and disease-related variables are related to recalling such discussions. Counseling about premature menopause and fertility changes is an overlooked aspect of preparation for adjuvant chemotherapy in young premenopausal women with breast cancer. Future research should explore this issue further.  相似文献   

12.
《Clinical breast cancer》2020,20(4):e410-e422
BackgroundYoung premenopausal women with breast cancer often experience more aggressive disease biology and poorer survival than older women. Diagnostic and therapeutic advances, including human epidermal growth factor receptor 2 (HER2)-directed therapy, may lessen treatment burden and improve survival for these young women, but contemporary incidence and survival data by HER2 status are limited.Patients and MethodsWe identified women aged 20-49 years (n = 68,530) diagnosed with stage I-III breast cancer during 2010-2016 from the United States Surveillance, Epidemiology, and End Results 18 registries database. Age-adjusted average annual percent changes in incidence (diagnosis 2010-2016) and 5-year Kaplan-Meier survival curves (diagnosis 2010-2015) were estimated by HER2 and hormone receptor (HR) status and stratified independently by cancer stage and race/ethnicity.ResultsWith increasing age decade, proportions of HER2/HR+ cancer increased, whereas proportions of HER2+/HR+, HER2+/HR, and HER2/HR decreased. The greatest increases in incidence during 2010-2016 were observed for HER2+ among women aged 20-49 years and HER2/HR among women aged 20-29 years. Incidence decreased for HER2/HR among women aged 40-49 years. Five-year survival was lowest for HER2/HR status compared to other receptor-based subtypes among women aged 20-49 years. HER2+ status was more beneficial for 5-year survival than HR+ status among women aged 20-29 years, with the opposite observed among women aged 30-49 years, particularly those aged 40-49 years.ConclusionHER2+ breast cancer increased among premenopausal women and was also associated with higher early survival within each HR status. HER2/HR cancer also increased among women aged 20-29 years and was associated with lower early survival. Our contemporary data provide important insights to help inform preventive and therapeutic strategies for premenopausal women.  相似文献   

13.
目的研究乳腺癌患者年龄及不同蒽环类化疗药物对化疗诱导停经的影响,为临床合理用药提供依据。方法前瞻性研究绝经前乳腺癌患者接受化疗后月经变化情况,比较不同年龄段及使用不同化疗药物的患者月经状态变化的差异。结果137例乳腺癌患者,化疗致闭经(CIA)的发生率为73.72%(101/137),长期闭经(LCIA)发生率为43.80%(60/137)。40岁以下患者CIA和LCIA的发生率均显著低于40岁以上的患者(X^2=25.32、18.42,P〈0.05),并且40岁以下组发生CIA后月经恢复率为61.90%(13/21),明显高于40岁以上组的35.00%(28/80),差异有统计学意义(X^2=4.99,P=0.025)。40岁以上患者中表柔比星(商品名:法玛新)、表柔比星(商品名:艾达生)、吡柔比星诱导LCIA率差异有统计学意义(X^2=6.92,P=0.031)。结论年龄是CIA的重要因素,40岁以下患者月经受化疗影响较小,停经多为可逆性。40岁以上患者使用不同的蒽环类化疗药物对月经状态的影响差异有统计学意义。  相似文献   

14.
Although previous studies have reported that onset at young age is associated with poor prognosis in breast cancer, the correlation between reproductive factors, breast cancer characteristics, and prognosis remains unclear. Five hundred and twenty-six premenopausal young women diagnosed with primary invasive breast cancer between January 2000 and December 2007 were included in this study. Patients were classified into four groups according to their reproductive history: women who gave birth within the previous 2 years (group A), women who gave birth between 3 and 5 years previously (group B), women who gave birth more than 5 years previously (group C), and nulliparous women (group N). The correlation between the time since last childbirth to diagnosis, histopathological tumor features, and breast cancer prognosis was evaluated. Breast cancer patients who had given birth more recently had more advanced stage tumors; larger sized tumors; a higher rate of axillary lymph node metastases; a higher histological tumor grade; and increased progesterone receptor (PgR)?, HER2+, and triple negative tumors than patients who had given birth less recently or not at all. Group A patients had significantly shorter survival times than patients in both groups C and N (log rank test; p < 0.001). After adjusting for tumor characteristics, the hazard ratio for death in group A was 2.19 compared with group N (p = 0.036), and the adjusted hazard ratio restricted to patients in group A with hormone-receptor-positive, and HER2? tumors was 3.07 (p = 0.011). Young breast cancer patients who had given birth more recently had tumors with more aggressive features and worse prognoses compared with patients who had given birth less recently or were nulliparous.  相似文献   

15.
The demonstration of the effectiveness of chemotherapy in both premenopausal and postmenopausal women, regardless of estrogen receptor (ER) status, raises the question of whether all breast cancer patients should receive chemotherapy. Several patient groups with such a favorable long-term prognosis that they will obtain an extremely small benefit from chemotherapy can be identified. They include patients with lymph node-negative tumors of 1 cm or less in size, those with grade 1 tumors between 1.1 and 2.0 cm in size, and those with tumors of favorable histologic type (tubular and mucinous) up to 3 cm in size. A patient subgroup in which it is not clear that the benefits of chemotherapy routinely exceed the risks is postmenopausal women with ER-positive, lymph node-negative cancers receiving tamoxifen. There is a wide variation in prognosis in this group, and chemotherapy should be reserved for those at high risk of recurrence. Finally, no benefit for chemotherapy in women aged 70 years and older has been identified. The high rate of death from causes other than breast cancer may negate small survival benefits, and after adjustment for quality of life, the duration of treatment exceeds the gain in life expectancy.  相似文献   

16.
Luteinising hormone releasing hormone agonists (LH-RHa) are effective in the treatment of advanced endocrine-sensitive breast cancer in premenopausal patients, but their role in the adjuvant setting has remained controversial for a long time.Tamoxifen for 5 years has been traditionally considered the standard endocrine therapy for premenopausal patients and this is still valid for many patients. However, the recently reported SOFT trial has suggested that adding ovarian function suppression (OFS) to tamoxifen could improve DFS in women at sufficient risk to warrant adjuvant chemotherapy and who remained premenopausal after this therapy. The administration of an aromatase inhibitor plus OFS represents an additional therapeutic option for hormone-receptor positive premenopausal breast cancer patients, according to the combined analysis of the SOFT and TEXT trials. Temporary ovarian suppression induced by LH-RHa has been recognized as an effective strategy to preserve ovarian function from the toxic effects of chemotherapy and is now recommended in young breast cancer patients with endocrine-insensitive tumors.In this review, we discuss recent data on the role of LH-RHa in combination with tamoxifen or with an aromatase inhibitor, and we comment on its role as a strategy to preserve ovarian function in young patients candidates for adjuvant or neo-adjuvant chemotherapy.  相似文献   

17.
Breast cancer is the most common cancer in women worldwide, accounting for just over 1 million new cases annually. Population-based statistics show that globally, when compared to whites, women of African ancestry (AA) tend to have more aggressive breast cancers that present more frequently as estrogen receptor negative (ERneg) tumors. ERneg tumors fail to respond to current established targeted therapies, whether for treatment or prevention. Subsets of the ERneg phenotype include those that are also negative for the progesterone receptor (PR) and HER2; these are called “triple negative” (TN) breast cancers. TN tumors frequently have pathological characteristics resembling “basal-like” breast cancers. Hence, the latter two terms are often used interchangeably; yet, despite extensive overlap, they are not synonymous. The ERneg, TN, and basal-like phenotypic categories are important because they carry worse prognoses than ER-positive (ERpos) tumors, in addition to lacking obvious molecular targets, such as HER2 and the ER, for known therapies. Furthermore, among premenopausal women the three subsets occur more frequently in women of African descent compared to white women with breast cancer. The contribution of these three subtypes of poor-prognosis tumors to the higher breast cancer mortality in black women is the focus of this review. We will attempt to clarify some of the issues, including risk factors, in terms of their contribution to that component of health disparities that involves biological differences in breast cancer between women of AA and white women.  相似文献   

18.
Background: The overall incidence of breast cancer in South Asian countries, including Nepal, is low comparedto Western countries. However, the incidence of breast cancer among young women is relatively high. Breastcancer in such cases is characterized by a relatively unfavorable prognosis and unusual pathological features.The aim of this study was to investigate clinico-pathological and biological characteristics in younger breastcancer patients (<40 years) and compare these with their older counterparts. Materials and Methods: Ninehundred and forty four consecutive female breast cancer patients, admitted to the Department of Surgery,Tribhuvan University Teaching Hospital, Kathmandu, Nepal between November 1997 and October 2012, wereretrospectively analyzed. Results: Out of the 944 female breast cancer patients, 263 (27.9%) were <40 years. Themean age was 34.6±5.0 years among younger patients compared to 54.1±9.9 for those ≥40 years. The mean age atmenarche was also significantly lower (13.5±1.5 vs 14.2±1.5 years p=0.001) while the mean duration of symptomswas significantly longer (7.6 vs 6.5 months p=0.004). Family history of breast cancer was evident in 3.0% of theyoung women versus 0.3% in the older one. Mammography was performed less frequently in younger patients(59.7%), compared to older (74.4%), and was of diagnostic benefit in only 20% of younger patients compared to85% of older ones. At diagnosis, the mean tumor diameter was significantly larger in young women (5.0±2.5 vs4.5±2.4cm, p=0.005). Axillary lymph nodes were positive in 73% of younger patients and 59% of older patients.In the younger group, the proportion of stage III or IV disease was higher (55.1% vs 47.1%, p≤0.05). Theproportion of breast conserving surgery was higher in young patients (25.1% vs 8.7%) and a higher proportionof younger patients receive neoadjuvant chemotherapy (9.9% vs 2.8%). The most common histological type wasductal carcinoma (93.1% vs 86%). The proportion of histological grade II or III was higher in younger patients(55.9% vs 24.5%). Similarly, in the younger group, lymphatic and vascular invasion was more common (63.2%vs 34.3% and 39.8% vs 25.4%, respectively). Patients in the younger age group exhibited lower estrogen and/or progesterone receptor positivity (34.7% vs 49.8%). Although statistically not significant, the proportion oftriple negative tumors in younger age group was higher (22.4% vs 13.6%). Conclusions: Breast cancer in youngNepalese women represents over one quarter of all female breast cancers, many being diagnosed at an advancedstage. Tumors in young women exhibit more aggressive biological features. Hence, breast cancer in young womenis worth special attention for earlier detection.  相似文献   

19.
Breast cancer is a common problem and a major health concern in our growing geriatric population. Older breast cancer patients are at risk for less than standard management, the appropriateness of which is difficult to discern. Breast tumors tend to have less aggressive characteristics. In addition, planning therapy is not always straightforward because older patients may present with comorbid illnesses and frailty that limit therapeutic choices. Standard management approaches should always be considered first. Here, we outline some data supporting standard treatment for breast cancer in older women. We also describe other options that can be considered in circumstances when the standard treatment is not possible. For instance, primary treatment with tamoxifen or an aromatase inhibitor is justifiable in a patient who is unfit for surgery and axillary dissection may be unnecessary in a patient who is obviously unfit for adjuvant chemotherapy. Adjuvant therapies should be considered, weighing risks and benefits for each patient, though the threshold for using chemotherapy may be higher. The goals in treating metastatic breast cancer in an older patient are not different than for younger patients.  相似文献   

20.
Breast cancer is mainly a postmenopausal disease, but in younger women breast tumors often exhibit more aggressive features and worse prognosis. Furthermore, high-risk and low-risk tumors present different age distributions suggesting that breast cancer comprises a mixture of two different disease processes. In agreement with this hypothesis, breast cancer presents different epidemiologic traits in pre- and postmenopausal women. Regarding racial distribution, incidence is higher in black women at younger ages in US, while the reverse is true among women older than 50 years. Genetic predisposition is a stronger risk factor in young women. On the contrary, nulliparity and obesity decrease the risk of early-onset breast cancers while are associated with higher incidence in older women. Epidemiologic data related with the hormonal exposure in utero suggest that the effect is stronger in early breast cancers. In most developed countries, breast cancer has shown an upward trend until recent years in postmenopausal women, while incidence rates in younger women have been stable. However, Spain is an exception to this rule: Spanish women younger than 45 years of age have registered a steady increase of breast cancer that may be related with the remarkable lifestyle changes experienced by women born in the second half of the twentieth century.  相似文献   

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