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PubMed1995

Risk assessment issues in breast cancer.

Breast cancer is the most common malignancy affecting women, and its incidence has been increasing in many countries. The aetiology of breast cancer is poorly understood, so there is concern as to which factors in our environment or lifestyle are responsible for the increase. There is a need for reliable risk assessment, which involves the steps of hazard identification, hazard evaluation, exposure evaluation and risk estimation. Short-term laboratory tests and long-term tests in animals are useful for priority-setting, but quantitative human risk assessment should preferably involve observations of humans. Epidemiological studies vary in the degree of reliance that can be placed on their results. The main types of epidemiological investigation are illustrated by recent examples from the literature on breast cancer. Careful judgement is required in assessing whether any association between a factor and a disease is likely to be causal. The injectable contraceptive, depot medroxyprogesterone acetate (DMPA, 'Depo-Provera'), has been controversial because it caused malignant mammary tumours in beagle dogs. Two recent case-control studies found no overall association between DMPA and the risk of breast cancer in women. There was some evidence of increased risk in certain sub-groups of women, which could be interpreted with more confidence if there were a better understanding of the biology of human breast cancer. Nevertheless, the results do not support the prediction from beagle experiments that DMPA might increase the overall risk of breast cancer.

Animals↗
PubMed2002

Somatic mutations in the BRCA2 gene and high frequency of allelic loss of BRCA2 in sporadic male breast cancer.

Breast cancer occurs rarely in men and risk factors for the disease include germline mutations of the BRCA2 gene. High frequency of allelic loss at the BRCA2 locus has been reported in sporadic breast tumors, but somatic mutations of BRCA2 are very rare. Here we report the first case of somatic BRCA2 mutation in male breast cancer with demonstrated loss of heterozygosity. We analyzed a series of 27 archival samples from male breast cancer patients for BRCA2 mutations and loss of heterozygosity at BRCA2 locus. The mutation analysis of BRCA2 gene was performed using SSCA-HA and sequencing methods. PCR was used to detect LOH at 3 highly polymorphic microsatellite markers spanning BRCA2 region on 13q by comparing the allelic pattern in matched tumor and blood DNA samples. In this study LOH at the BRCA2 locus was observed in 82.6% of informative cases, confirming previous observations on high frequency of LOH affecting the BRCA2 region in male breast cancer. We identified 5 somatic BRCA2 mutations in a set of 23 sporadic male breast cancers (21%). Two silent and 1 missense alterations were novel BRCA2 variants. Here we also report first somatic frameshift BRCA2 mutation in male breast cancer 8138del5. In 3 tumors with somatic BRCA2 alterations, 1 missense, 1 silent and frameshift LOH at chromosome 13q12-13 were detected and losses involved a wild-type allele of BRCA2 gene.

BRCA2 Protein↗
PubMed1986

Risk factors of multiple primary cancers in breast cancer patients.

To clarify risk factors of multiple primary cancers in breast cancer patients, a case-control analysis based on data from medical records was conducted at the Aichi Cancer Center Hospital. For each of a total of 115 multiple primary cancer patients affected by one or two other primary cancers after or concurrently with breast cancer, two patients with unilateral breast cancer were selected as controls by matching age, time of the operation for breast cancer, and survival period. Multiple primary cancer patients were then divided into two groups, 61 cases of bilateral breast cancer and 56 cases of other multiple primary cancers. Conditional multiple logistic regression analysis indicated that relatively heavy smoking (more than 10 cigarettes per day) decreased the risk of multiple primary cancers taken overall (relative risk (RR) = 0.23); overweight status elevated the risk of bilateral breast cancer (RR = 3.01); and greater than average height (RR = 2.20), history of gallstone or cholecystitis (RR = 6.29), and late first birth or nulliparous status (RR = 6.85) elevated the risk of other multiple primary cancers. The effects of weight and height were predominant in the postmenopausal women. As to family history, we could not obtain clear results, though history of cancer among siblings tended to increase the risk of multiple primary cancers (P less than 0.10) and family history of breast cancer was more frequent in patients with bilateral breast cancer (not significant).

Alcohol Drinking↗
PubMed2007

Chromosomal changes associated with clinical outcome in lymph node-negative breast cancer.

Breast cancer is the most common malignancy among women and accounts for over one million new cases worldwide per year. Lymph node-negative breast cancer patients are reputed as having a better prognosis than lymph node-positive ones. Around 20% of the lymph node-negative patients die within 10 years after diagnosis. To improve the prognostics of node-negative breast cancer, it is important to understand the underlying biologic mechanisms promoting survival, such as specific genetic changes in the tumor genome. In this study, CGH was applied to analyze 64 tumors from node-negative breast cancer patients to identify DNA copy number changes in chromosomes and chromosome regions that may be correlated to survival. The main findings show gains at 4q, 5q31 approximately qter, 6q12 approximately q16, and 12q14 approximately q22, as well as losses of 17p, 18p, and Xq, which were significantly more recurrent in tumors from deceased patients than in tumors from survivors. The average number of chromosomal changes was higher in the tumors from deceased compared to the survivor tumors. Our findings suggest that tumors with specific chromosomal aberrations at 4q, 5q31 approximately qter, 6q12 approximately q16, 12q14 approximately q22, 17p, 18p, and Xq result in an aggressive form of breast cancer and that these patients are predisposed to succumb to breast cancer.

Adult↗
PubMed2005

Clinical application of molecular profiling in breast cancer.

Breast cancer is the leading type of cancer and second leading cause of cancer death in women. Breast cancer mortality has declined over the past 10 years largely due to early detection by mammographic screening, but also in part due to the increasing use of adjuvant hormonal therapy and chemotherapy. Indications for adjuvant chemotherapy have now expanded to include women who are at low risk of recurrence, resulting in overtreatment of most women to benefit a few, particularly those with favorable clinical features. New techniques have been evaluated that identify specific molecular signatures that may more accurately predict prognosis than clinical features, and that may also identify individuals who are more likely to benefit from endocrine therapy and/or chemotherapy. This review will focus on the clinical applications of these novel techniques reported to date, and how this may lead to the incorporation of molecular diagnostics into clinical practice. Two prospective, multicenter, multinational Phase III trials evaluating tumor genomic profiling in breast cancer are currently in development, and will be initiated within the forthcoming year. The completion of these important studies will represent the first step toward integrating molecular profiling into treatment selection for adjuvant therapy in breast cancer.

Antineoplastic Agents↗
PubMed2001

Her-2/neu and breast cancer.

Breast cancer is the most common malignancy in women in the United States in the year 2000. The proto-oncogene Her-2/neu (c-erb-B2) has become an increasingly important prognostic and predictive factor in breast cancer. Overexpression/amplification of the Her-2/neu has been associated with a worse outcome in patients with breast cancer. Herceptin, a "humanized" murine monoclonal antibody directed against the extracellular domain of the Her-2/neu protein, is being used to treat breast cancer that overexpresses Her-2/neu. The status of Her-2/neu in the tumor has become a critical factor in the management strategy of a breast cancer patient. The objective of this article is to provide a comprehensive review of all aspects of Her-2/neu in breast cancer, including biology, prognostic and predictive value, targeted Herceptin therapy, and the laboratory testing of Her-2/neu.

Adenocarcinoma↗
PubMed1990

Opportunities in clinical trials. Adjuvant breast cancer.

Breast cancer is the most common cancer in women in the US, with approximately two-thirds of patients presenting with tumors confined to the breast alone or breast and ipsilateral axillary lymph nodes. Although all of these women can be rendered free of detectable breast cancer by local therapeutic modalities, many will experience recurrences regionally or at distant sites. Nearly all patients who have distant recurrences will subsequently die of breast cancer. Although metastatic breast cancer responds to a variety of hormonal and chemotherapeutic interventions, it is rare that such therapy is curvative. Hence, there has been great interest in studying adjuvant systemic therapies. There is now a long clinical trial experience with adjuvant therapy in breast cancer that provides an extensive background for implementing recent advances in molecular and cellular biology in the clinical setting. Predictably, these laboratory-clinical correlations will provide important leads for future generations of randomized adjuvant trials, both by helping to target new therapies for particular subsets of patients and by identifying prognostic groups. In this report, current efforts in adjuvant therapy trials and laboratory-clinical correlations being conducted in conjunction with those trials are described.

Breast Neoplasms↗
PubMed1997

Immunological enhancement of breast cancer.

Breast cancer is a complex disease. Its aetiology is multifactorial, its period of development can span decades, and its clinical course is highly variable. Evaluation of the role of the immune response in either the development or control of breast cancer is also complex. Nevertheless, there is substantial information that in this disease, the immune response is not a host defence reaction and may even serve to facilitate cancer development. This evidence comes from a variety of sources including clinical-pathological investigations in women that show a correlation between the intensity of lymphocytic infiltration into the tumour mass with poor prognosis, studies in breast cancer patients that demonstrate a similar correlation between delayed hypersensitivity reactivity or in vitro assays of immune reactivity to tumour cell membranes or non-specific antigens and poor prognosis, and analyses of cancer incidence in chronically immunosuppressed, kidney transplant recipients who develop an unexpectedly low incidence of breast cancer. The overall conclusions from these human studies are corroborated by observations in mouse mammary tumour models that also demonstrate immune enhancement of breast cell proliferation in vitro and of breast cancer development in vivo. Potential mechanisms for these effects include production, by inflammatory cell infiltrates, of direct or indirect modulators of breast cell growth, e.g. cytokines, peptide or steroid hormones, enzymes involved in steroid metabolism, as well as of antibodies to growth factors or their receptors. These immune facilitatory mechanisms must be overcome if immune-based therapies are to be applied successfully in breast cancer.

Animals↗
PubMed1996

Retinoid receptors in human lung cancer and breast cancer.

Retinoids, the natural and synthetic vitamin A derivatives, are known to inhibit the proliferation of lung cancer and breast cancer cells and the growth of carcinogen-induced bronchogenic squamous cell carcinoma and mammary tumors, and have been used as chemoprevention agents against both types of cancer. However, clinical trials of retinoids in patients with advanced lung cancer and breast cancer have not been successful. In studying how retinoid sensitivity is lost in cancer cells, we have found that lack of the retinoic acid receptor beta (RAR beta) gene expression and its abnormal regulation by retinoic acid (RA) are common features in human lung cancer and breast cancer cells. The absence and abnormal RA regulation of RAR beta correlates with the loss of anti-proliferation effect of RA in hormone-independent breast cancer cells, and is due to different abnormalities found in cancer cells. Furthermore, expression of RAR beta gene in hormone-independent breast cancer cells restores their RA sensitivity. These data demonstrate that RAR beta can mediate the growth inhibitory effect of RA and suggest that the lack of RAR beta may contribute to retinoid resistance in certain cancer cells.

Breast Neoplasms↗
PubMed2003

Advancements of antisense oligonucleotides in treatment of breast cancer.

Breast cancer is one kind of multi-gene related malignancy. Overexpression of some oncogenes such as HER-2 (c-erbB-2, Neu), bcl-2/bcl-xL, protein kinase A (PKA), and transferrin receptor gene (TfR gene), etc significantly affect the prognosis of breast cancer. It was shown that specific suppression of the overexpressed genes above resulted in the improvement of the therapy of breast cancer. Antisense interference, one of useful tools for inhibiting the overexpression of specific oncogenes, was involved in the therapy of breast cancer in recent years. Data indicated that antisense oligonucleotides (ON) could inhibit specially the expression of the target genes on mRNA or protein levels in most of cases; some ON candidates showed encouraging therapeutic effects in vitro and in vivo on breast cancer cell lines or xenografts. Furthermore, the combination use of the antisense ON and normal chemotherapeutic agents indicated synergistic antitumor effects, which was probably the best utilization of antisense ON in the treatment of breast cancer.

Animals↗
PubMed2003

Racial differences in genetic factors associated with breast cancer.

Breast cancer in African Americans in the US is more aggressive and has a worse outcome than breast cancer in Caucasians. Although the incidence of breast cancer among US whites is higher than among blacks, the mortality rates for blacks are much higher. Breast cancer in blacks is also associated with a more advanced stage at presentation and pathologically aggressive tumors commonly exhibiting estrogen receptor negativity, higher S-phase fractions, and higher numbers of involved lymph nodes. This paper reviews some of the genetic factors that have been shown to be associated with a difference in breast cancer outcome between African Americans and Caucasians in the US such as the BRCA1 and BRCA2 genes, p53 mutations, UGT1A1 gene polymorphisms, and HER-2/neu gene amplifications/overexpression.

Black or African American↗
PubMed2002

Microsatellite instability in early-onset breast cancer.

Breast cancer in a young person is considered a rare and very aggressive disease. The theories addressing the underlying genetic mechanisms of this disease are controversial. Therefore, additional genetic concepts playing a possible role in its pathogenesis and prognosis must be investigated. Microsatellite instability (MSI) characterized by a mutational process of insertions or deletions in microsatellite repeats might constitute a sensitive indicator for genomic instability in cancer. MSI has been described in a wide variety of tumors, particularly in hereditary non-polyposis colorectal cancer. The reports regarding its occurrence and prognostic significance in breast cancer are in conflict with each other. The purpose of this study was to investigate MSI in early-onset breast cancer and to correlate its occurrence with clinicopathological prognisticators. In this study, 16 female patients with primary breast cancer under 35 years of age (range 29-34) were investigated for the incidence of MSI in five microsatellite loci (D2S123, D3S1611, D17S807, D17S796 and Xq11-12) by comparing paired normal and tumor tissue DNA after PCR amplification from paraffin-embedded tissues. No instability was found in any of these five microsatellite loci. Although care must be taken not to overstate the importance of this result due to the inadequate number of microsatellite markers and DNA samples studied, this preliminary report indicates that MSI phenotype is uncommon in human early-onset breast cancer. Therefore, it does not appear to be related to the prognosis of disease.

Adult↗
PubMed2003

Environmental pollutants and breast cancer.

Breast cancer is the most common cancer in women and the leading cause of cancer death among women 35-54 years of age. Rising incidence, increased risk among migrants to higher risk regions, and poor prediction of individual risk have prompted a search for additional modifiable factors. Risk factors for breast cancer include reproductive characteristics associated with estrogen and other hormones, pharmaceutical hormones, and activities such as alcohol use and lack of exercise that affect hormone levels. As a result, investigation of hormonally active compounds in commercial products and pollution is a priority. Compounds that cause mammary tumors in animals are additional priorities. Animal models provide insight into possible mechanisms for effects of environmental pollutants on breast cancer and identify chemical exposures to target in epidemiologic studies. Although few epidemiologic studies have been conducted for chemical exposures, occupational studies show associations between breast cancer and exposure to certain organic solvents and polycyclic aromatic hydrocarbons (PAHs). Population-based studies have been limited to a few organochlorine compounds and PAHs and have been mostly negative. A variety of challenges in studies of breast cancer and the environment may have contributed to negative findings. Lack of exposure assessment tools and few hypothesis-generating toxicologic studies limit the scope of epidemiologic studies. Issues of timing with respect to latency and periods of breast vulnerability, and individual differences in susceptibility pose other challenges. Substantial work is needed in exposure assessment, toxicology, and susceptibility before we can expect a pay-off from large epidemiologic studies of breast cancer and environment.

Alcohol Drinking↗
PubMed2002

C-erbB-2 expression does not predict response to docetaxel or sequential methotrexate and 5-fluorouracil in advanced breast cancer.

Breast cancer patients with c-erbB-2-positive tumours seem to benefit from anthracycline-based adjuvant chemotherapy. The predictive value of c-erbB-2 for taxane sensitivity is not yet clear. The purpose of this study was to assess whether c-erbB-2 expression is associated with clinical sensitivity to docetaxel (T) or sequential methotrexate and 5-fluorouracil (MF). A total of 283 patients with metastatic breast cancer were initially enrolled in a randomised multicentre trial comparing docetaxel with sequential MF in advanced breast cancer. Paraffin-embedded blocks of the primary tumour were available for 131 patients (46%). c-erbB-2 status was determined by immunohistochemistry using a polyclonal antibody to the c-erbB-2 protein. C-erbB-2 expression was scored in a semi-quantitative fashion using a 0 to 3+ scale. Staining scores 2+ or greater were considered positive. Response evaluation was performed according to World Health Organization (WHO) recommendations. Overall 54 (42%) patients had c-erbB-2-positive tumours. There was no association between treatment outcome and c-erbB-2 overexpression. The overall response rates (RR) (n=128) among c-erbB-2-negative and -positive patients were 35 and 44%, respectively (P=0.359). In the MF arm (n=62), the RR was somewhat higher in the c-erbB-2 overexpressors (33% versus 18%, P=0.18). In the docetaxel arm the RRs were very similar, regardless of the c-erbB-2 expression (53% versus 53%). While several studies have suggested a prognostic and putative predictive significance of c-erbB-2 overexpression in early breast cancer, the significance of c-erbB-2 expression as a predictive factor for response to various cytotoxic treatments in advanced breast cancer is still controversial. In this study, c-erbB-2 expression could not predict response to either MF or T. Thus, tumours over-expressing c-erbB-2 are not uniformly more sensitive to taxanes and c-erbB-2 expression cannot yet be applied clinically as a predictive factor for response in advanced breast cancer.

Adolescent↗
PubMed2006

A measles virus vaccine strain derivative as a novel oncolytic agent against breast cancer.

Breast cancer is the most common malignancy and the second leading cause of female cancer mortality in the United States. There is an urgent need for development of novel therapeutic approaches. In this study, we investigated the antitumor potential of a novel viral agent, an attenuated strain of measles virus deriving from the Edmonston vaccine lineage, genetically engineered to produce carcinoembryonic antigen (CEA) against breast cancer. CEA production as the virus replicates can serve as a marker of viral gene expression. Infection of a variety of breast cancer cell lines including MDA-MB-231, MCF7 and SkBr3 at different multiplicities of infection (MOIs) from 0.1 to 10 resulted in significant cytopathic effect consisting of extensive syncytia formation and massive cell death at 72-96 h from infection. All breast cancer lines overexpressed the measles virus receptor CD46 and supported robust viral replication, which correlated with CEA production. TUNEL assays indicated an apoptotic mechanism of syncytial death. The efficacy of this approach in vivo was examined in a subcutaneous Balb C/nude mouse model of MDA-MB-231 cells. Intravenous administration of MV-CEA at a total dose of 1.2 x 10(7) TCID50 resulted in statistically significant tumor growth delay ( p=0.005) and prolongation of survival ( p=0.001). In summary, MV-CEA has potent antitumor activity against breast cancer lines and xenografts. Monitoring marker peptide levels in the serum could serve as a low-risk method of detecting viral gene expression during treatment and could allow dose optimization and individualization of treatment. Trackable measles virus derivatives merit further exploration in breast cancer treatment.

Animals↗
PubMed1993

Primary reconstruction after chest wall resection in breast cancer.

Breast cancer patients with chest wall recurrence or patients with advanced breast cancer pose a difficult challenge to surgeons. Surgical ablation results in not only a large soft tissue defect that needs cover but often, in addition, a significant bony chest wall defect. The majority of these patients would have already received irradiation or chemotherapy or both. Thus, wound healing is significantly impaired. For these reasons, surgery was previously not attractive as an alternative in the palliation of these patients. Over a one-year period, seven breast cancer patients had chest wall resection. Six patients had recurrent tumours and one had advanced primary breast cancer. Two of these patients required only extensive resection of soft tissue of the anterior chest wall. The other five patients required, in addition, resection of the bony chest wall. Myocutaneous flaps were used to repair the surgical defects in six of these patients. Five were rectus abdominis myocutaneous flaps and one a pectoralis major myocutaneous flap. In one patient, a deltovertebral skin flap, which is an axial pattern skin flap was used. Primary wound healing was achieved in five of six patients (83%). One patient died immediately post-operatively, the cause of which is unknown. One of the rectus abdominis flap needed an exploration but was ultimately salvaged. This paper demonstrates the usefulness of the myocutaneous flap in enabling surgery to become a modality for palliation of patients with recurrent and advanced breast cancer.

Adult↗
PubMedDate not supplied

Cutaneous metastatic breast cancer.

Breast cancer is the most commonly diagnosed cancer in women and the second leading cause of cancer deaths among women in the United States. Many women diagnosed with breast cancer will achieve a cure with surgery followed by adjuvant chemotherapy, hormonal therapy, or radiation therapy; however, some breast cancer survivors will develop locally recurrent disease. Skin metastases are one of the most distressing presentations of locally recurrent breast cancer. The purpose of this article is to increase oncology nurses' understanding of the pathophysiology of cutaneous metastases, facilitate recognition of the various presentations of cutaneous metastatic breast cancer, discuss management of both the underlying disease process and skin lesions, and identify issues of psychosocial support for patients and families throughout the continuum of illness.

Breast Neoplasms↗
PubMed2005

The etiology of alcohol-induced breast cancer.

Breast cancer is the most common cancer in women in the United States, and it is second among cancer deaths in women. Results of most epidemiologic studies, as well as of most experimental studies in animals, have shown that alcohol intake is associated with increased breast cancer risk. Alcohol consumption may cause breast cancer through different mechanisms, including through mutagenesis by acetaldehyde, through perturbation of estrogen metabolism and response, and by inducing oxidative damage and/or by affecting folate and one-carbon metabolism pathways. Alcohol-metabolizing enzymes are present in human breast tissue. Acetaldehyde is a known, although weak, mutagen. However, results of some studies with human subjects implicate this agent in the context of genetic susceptibilities to increased ethanol metabolism. Reactive oxygen species, resulting from ethanol metabolism, may be involved in breast carcinogenesis by causing damage, as well as by generating DNA and protein adducts. Alcohol interferes with estrogen pathways in multiple ways, influencing hormone levels and effects on the estrogen receptors. With regard to one-carbon metabolism, alcohol can negatively affect folate levels, and the folate perturbation affects DNA methylation and DNA synthesis, which is important in carcinogenesis. Some study results indicate that genetic variants of one-carbon metabolism genes might increase alcohol-related breast cancer risk. For all these pathways, genetic polymorphisms might play a role in increasing further a woman's risk for breast cancer. Additional studies are needed to determine the relative importance of these pathways, as well as the modifying influence by genetic variation.

Alcohol Drinking↗