breast cancer - Symptoms - Signs - Screening - Treatment

Breast Cancer Cause

Genetic and lifestyle factors  have important but incompletely understood roles.

Breast Cancer and Family History The significance of breast cancer in the family on the chance of another family member being affected is disputed. Early studies found the risk ratio (Q33.27) for developing breast cancer to be 1.9 if the mother has had cancer of the breast and 2.3 if the disease had affected a sister. There is virtually no increased risk for more distant relatives. However, a meta-analysis (Q33.23) could find no evidence that there as an increased risk of breast cancer even if a close relative had the disease. A meta-analysis of 51 studies, reported in The Lancet in 1997 evaluating the relationship between HRT and breast cancer demonstrated no increased risk for those whose mothers or sisters have had breast cancer to those with no family history.

For some women with a very strong history of breast or ovarian cancer it may be appropriate to test for the high penetrance breast cancer susceptibility gene BRCA1 (breast cancer 1). This gene is located on chromosome 17. More intensive and frequent screening of those at increased genetic risk would appear to be appropriate. It is wise for the implications to be carefully addressed by a counsellor before the test is performed. It may be that we shall be able to provide a degree of reassurance, for some women at least, when there is a history of breast cancer in the family.

Other genes are currently being evaluated in several research centres.

Hormones: One cause of breast cancer is prolonged endogenous female sex hormone production - early puberty and late menopause. This is supported by epidemiological evidence and clinical trials confirming the therapeutic benefit of anti-oestrogenic therapy in the treatment and prevention of hormone- sensitive (that is, oestrogen-receptor positive) disease. However, breast cancer development is complex.

The association of HRT with an increased risk of breast cancer is well recognized but has attracted disproportionate attention following recent publications that have in turn resulted in conflicting advice from regulatory authorities. This has reduced health professional and patient confidence in HRT and triggered a dramatic decline in HRT prescribing.

In a few studies, reduced breast cancer mortality in women who used hormone therapy before diagnosis have been observed . Due to the high prevalence of past and current hormone use, it is important to investigate whether these preparations are related to breast cancer mortality.

To evaluate the influence of prediagnostic use of hormone therapy on breast cancer mortality, a prospective cohort of 12,269 women ages 50 years or more diagnosed with incident invasive breast cancer and residents of Wisconsin, Massachusetts, or New Hampshire were enrolled in three phases beginning in 1988. They were followed for death until December 31, 2005, using the National Death Index. During an average 10.3 years of follow-up, 1,690 deaths from breast cancer were documented. Cumulative mortality from breast cancer was lower among hormone therapy users, specifically current users at the time of diagnosis, and oestrogen/progestogen users, compared with nonusers. No association was observed for women who were former or current users of oestrogen-alone preparations. Although use of combined oestrogen/progestogen preparations increases breast cancer risk, in this study, use of these hormones before diagnosis was associated with reduced risk of death after a breast cancer diagnosis.⁰⁸⁰¹

Prediagnostic use of hormone therapy and mortality after breast cancer.(2008-01)

breast cancer and Early pregnancy loss

Anti-Termination of Pregnancy Groups have claimed that pregnancy termination increases the risk of breast cancer by 30%. There would appear to be no foundation for this contention according to a study by Michels et al.⁰⁷⁰¹ They found no increased risk of breast cancer in women with a history of pregnancy termination or spontaneous miscarriage.

Induced and spontaneous abortion and incidence of breast cancer among young women: a prospective cohort study.

breast cancer and the combined oral contraceptive pill.

Breast cancer is common with more than 600,000 new cases reported internationally each year. Many studies have been undertaken to determine whether the pill might place women at increased risk of breast cancer

The results of meta-analyses (Q33.23) are reasonably reassuring with at most a marginal increase. This must be balanced against several pill benefits including reduction in the risk of ovarian and endometrial cancer, fibroids, ovarian cysts, endometriosis, benign breast disease and ectopic pregnancy. Those women found to have breast cancer whilst taking the pill are usually diagnosed at an early stage so that the prognosis is relatively good.

breast cancer Statistics

Every three minutes a woman in the United States is diagnosed with breast cancer. In 2006, an estimated 212,920 new cases of invasive breast cancer were diagnosed, along with 61,980 new cases of non-invasive breast cancer. 40,970 women died in 2006 from this disease.

breast cancer is the leading cancer among white and African American women. African American women are more likely to die from this disease.

breast cancer incidence in women has increased from one in 20 in 1960 to one in eight today.

Although the incidence of breast cancer has been increasing, deaths have been falling - Figure 1

Figure 1 Incidence and mortality from breast cancer 1975 to 2005 in Great Britain.

(http://info.cancerresearchuk.org/cancerstats/mortality/timetrends/)

 

Cancer In Women	Risk Factors For breast cancer	Breast Cancer Statistics	Breast Cancer Screening	Breast Cancer Screening Benefits - Mammograph and Mammograms	Breast Cancer Cause
Breast Cancer and Family History		Breast Cancer Treatment		Breast Cancer Support Groups

 

 Interventions (PEPI) Investigators.(1999-01)

Breast Cancer Screening Benefits - Mammograph and Mammograms

Self-Examination:

• The majority of doctors would advocate self-checking on a regular basis. More than 90% of breast cancers are found by the woman herself. If any change is noted, early assessment by the doctor is to be highly recommended.
• The breast tissue becomes more nodular (lumpy) before each period so that it is best to undertake examination after a period.
• The breasts are composed of lobes of glandular tissue that can be felt between the thumb and the fingers by gentle squeezing this is therefore not the method to examine the breast for lumps or thickening.
• The hand should be closed and flat with the fingers being gently but firmly pressed in and moved to feel for swellings.
• Imagine each breast in four quarters and systematically check each of these areas.
• Other changes such as discharge or bleeding from the nipple should also be reported to your general practitioner.

The merits of a screening test are listed in screening tests. With reference to Q32.8:-

• Breast cancer is an important health risk (A). There are 24,000 new cases and 15,000 deaths reported annually in theUK .
• Breast cancer is the commonest cancer in women in theUK (B). One women in twelve (7.5%) will develop breast cancer at some time in her life.
• The majority of breast cancers are found in women over the age of 55 years. We know a lot about the natural history of the disease (C). When the tumour is limited to a duct or measures less than 1 cm, spread to the lymph glands is least likely to have occurred. Screening aims to detect this early stage of disease.
• The five year survival for stage 1 breast cancer (less than 2 cm) with appropriate treatment is 84% whereas it falls to 18% for stage 4 disease (D). The UK screening programme (mammography) costs 37 million per year.
• An evaluation in 1986 found that the cost per quality-adjusted life year (a year of good health quality) achieved by screening compared favourably to other approved and established screening programmes (E).
• Mammography has
  • high specificity (low false negatives – (F)
  • and sensitivity (low false positives - G).

In the three years from 1992, 4,729,003 women aged 50-65 were offered mammography – 3,582,332 (75.8%) accepted (H). Breast biopsies were required for 24,651 women (0.69% of those having mammograms. breast cancer was identified 19,792 (0.55%). Cancer of 1 cm or less was found in 5,785 (0.16%).

It is not known if all invasive breast cancers begin as ductal carinoma in situ lesions (pre-malignant). Not all early abnormalities undergo calcification and mammography, looking for calcification, may not be the most effective way of diagnosing early lesions. A prospective study from Germany has compared mammography with MRI. The MRI proved more effective in diagnosing early lesions.⁰⁷⁰¹

Being screened for breast cancer reduced breast cancer deaths by 48% in a study in East Anglia following the introduction of screening in 1989.²⁰⁰⁸

It might be assumed that computer assisted detection of abnormality on mammography would enhance interpretation. In practice, the use of computer-aided detection is associated with reduced accuracy of interpretation of screening mammograms. The increased rate of biopsy with the use of computer-aided detection is not clearly associated with improved detection of invasive breast cancer.⁰⁷⁰²

The ideal interval for breast cancer screening has yet to be established. The UK was one of the first to offer national breast screening with mammography. All women aged 50 – 64 are offered screening at three year intervals. The Department of Health is currently assessing the potential of extending the upper limit of screening to the age of 69. Most European programmes screen at two year intervals. A British trial looking at this interval is due to report in 1998. The Cancer Research Campaign is evaluating the possible benefits of mammography starting at age 40.

The breasts in younger women are usually too dense for interpretation of x-ray mammography. Sonography (ultrasound examination of the breast) is accurate but the investigation requires considerable expertise and is time-consuming.

Compression of the breast during mammography can be painful but the discomfort is just for a short time.

Mammography involves radiation. Current evidence suggests that, at most, mammography could be the cause of cancer in one woman for every two million women screened.

Whereas cervical screening is designed to pick up cervical disease before it becomes malignant, breast cancer screening is designed to pick up the disease when it has already become active although hopefully early enough to provide curative treatment.

Nine out of ten women found to have an abnormality on mammography do not have cancer. If an abnormality is detected on the mammogram a sample of tissue is taken by the breast specialist often under local anaesthetic. A pathologist will then examine this biopsy microscopically to provide the definitive diagnosis. The emotive issues around breast screening, the need for quick evaluation and access to specialist consultation and treatment are being increasingly recognised by many units.

There is some concern that HRT (hormone replacement therapy) reduces the accuracy of mammography. Observational studies have shown HRT to reduce sensitivity (ability to detect an abnormality) and therefore increase interval cancer rates (cancer diagnosed between mammographic screens due to being missed at a previous screen).9 HRT is also reported to reduce specificity (ability to differentiate cancer from non-cancerous change), leading to an increase in false positive recall.⁰¹⁰¹

HRT is also reported to reduce specificity (ability to differentiate cancer from non-cancerous change), leading to an increase in false positive recall.^{0601, 0602} However, only combined therapy of oestrogen with progestogen, significantly increases mammographic breast density and hence potentially affects sensitivity.9901 Almost all the increase occurs in the first year and affects about 1 in 4 women. The mammographic density increase with the combined HRT is in the order of 6%.⁰⁵⁰¹

Related Medical Abstracts - Click on the paper title:-

 

Cancer In Women	Risk Factors For breast cancer	Breast Cancer Statistics	Breast Cancer Screening	Breast Cancer Screening Benefits - Mammograph and Mammograms	Breast Cancer Cause
Breast Cancer and Family History		Breast Cancer Treatment		Breast Cancer Support Groups

Breast Cancer Treatment

Premenopausal women with early breast cancer are usually treated with tamoxifen and/or chemotherapy after surgery. As their ovaries are producing oestrogen and progesterone, it may be advantageous to suppress ovarian function with Gonadotrophin Releasing Hormone (GnRH) if the tumour is receptor positive. A meta-anlysis has demonstrated their effectiveness. The optimum duration of treatment is unknown.⁰⁷⁰¹

Evidence from the International breast cancer Trialists Collaborative Group have found that any woman with hormone sensitive breast cancer would benefit from tamoxifen regardless of her age or menopausal status. Tamoxifen has been shown to protect substantially against breast cancer recurrence and death. These conclusions were derived from a meta-analysis (Q33.23) of 55 trials involving 37,000 women. In the group of women with oestrogen sensitive tumours or those with unknown oestrogen sensitivity, there was a 47 % reduction in recurrence rate over ten years following five years of tamoxifen treatment. The survival rate was improved by 11 % over ten years. Tamoxifen was associated with a slight increase in the incidence of endometrial cancer.

For the past 30 years, tamoxifen has saved millions of lives throughout the world. The same has been proven in randomized trials and meta-analyses. Recent trials have shown clinical superiority of aromatase inhibitors over tamoxifen in terms of disease free survival and reduction in complications. However, because of the unique mechanism of tamoxifen, intrinsic advantages and low cost, this wonder drug may still be a reasonable choice for hormonal therapy in breast cancer.⁰⁸⁰¹

Related Medical Abstracts - Click on the paper title:-

Support Groups

Members of a support group, provide each other with various types of help and information for a particular shared difficulty. The support may take the form of providing relevant information, relating personal experiences, listening to others' experiences, providing sympathetic understanding and establishing social networks. A support group may also provide ancillary support, such as serving as a voice for the public or engaging in advocacy. Support groups maintain interpersonal contact among their members in a variety of ways. Support groups also maintain contact through printed information rich newsletters, telephone chains, internet forums, and mailing lists.

Support groups offer companionship and information for people coping with diseases or disabilities. Support groups may not be appropriate for everyone, and some find that a support group actually adds to their stress rather than relieving it.

Evaluation of the quality of Web sites is discussed in(Q4.27) . You may find that several general women's health sites may help you (internet information). The following are more specialised relevant Web sites:-

DISCLAIMER

The aim of this web site is to provide a general guide and it is not intended as a substitute for a consultation with an appropriate specialist in respect of individual care and treatment.

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