Literature Review Outline
Breast Cancer Screening Techniques in High Risk Women Teresa Roberts-Coiner Boise State University CHAPTER II Review of Literature Introduction The following is a summary of the published literature that examines the scope of screening for breast cancer in high risk women as well as genetic and enviornmental risk factors that contribute to breast cancer. Women, who carry a mutation of the breast cancer gene, known to healthcare providers as BRCA1 and BRCA2, have a 55-87% lifetime risk of developing breast cancer (Ozanne, et al. , 2006).
A review of the multiple modalities used to detect tumors early before the cancer has metastasized, the efficacy of modalities in diagnosing breast cancer and a brief history of how these modalities can increase awareness of breast cancer for patients and healthcare providers is also discussed. In addition, a review of evidence-based practice gives outcomes of studies done supporting best practice guidelines. The purpose of the proposed non-experimental research study is to examine a sample of the population of healthcare providers (OB-GYN, Family Practice, mid-levels, e. . Nurse Practitioners and Physician Assistants) in the Treasure Valley to determine what screening techniques they use most often for their female patients identified as high risk for developing breast cancer. A survey research questionnaire and/or telephone interview would be the methods considered for use. Breast Cancer Screening and Diagnosis In the United States, breast cancer is the most common cancer among women and the primary cause of death in women between the ages of 45-60 (Ozanne, Wittenberg, Garber and Weeks, 2009).
In addition to the emotional and physical costs, there can be tremendous financial costs to patients and their families. Survival has clearly improved during the last decade, mainly as a result of earlier detection by women’s awareness and mammography screening, and also by increase used of chemotherapy (Ozanne, 2009). If a breast cancer is detected in situ (very early stage), the 5-year survival is 98%, compared with 81% with regional spread and with 26% metastases (Sinicrope et al. , 2008).
Guidelines for breast cancer screening have been under scrutiny, the most controversial area has been annual radiographic screening for women younger than 50 years (Glasziou & Houssami, 2011). Glasziou notes there is controversy with levels of informed consent with potential harm from screenings as well as high rates of false positive and negatives among younger women. Ozanne, et al. (2009) conducted a study to investigate prevention, decision- making among women at high risk for breast cancer. A prospective interview and survey study was conducted.
One hundred and forty six of 217 eligible patients participated. The results indicated that patients typically underestimated their risk of breast cancer and physicians over-estimated the decrease in perceived risk (Ozanne, 2009). Breast cancer risk assessment coupled with risk communication counseling enables the identification of women at increased risk for breast cancer, yet it also demands an understanding of how women at higher risk understand their level of risk and options available (Ozanne et al. , 2009). Risk Factors
Fixed factors include personal history, family history, genetics, breast density, reproductive and menstrual history, long-term use of hormone therapy, alcohol and physical activity level (Ozanne et al. 2009). The strongest risk factor for breast cancer is age. Most breast cancers occur in women over the age of 50 (NCI Fact Sheet Probability of Breast Cancer in American Women, 2010). Modifiable risk factors include smoking, use of hormone therapy, alcohol consumption, BMI, diet, physical activity and breast feeding (Dr.
Pierson presentation October 11, 2011). Studies have shown that women having a first degree relative with breast cancer are at a 2-3 times higher risk of developing the cancer compared to women with no family history (Sinicrope et al. , 2008). Women whose breasts appear mammographically dense have a three-to fivefold increase risk of breast cancer (Ozanne et al. , 2006). Screening efforts have shown that early detection is more difficult in women with radiographically dense breasts (Ozanne et al. , 2009). Women who are at high risk tend to develop cancer at younger age, making mammographic screening less conclusive due to the increased density of breast tissue in younger women (Ozanne, et al. , 2009). In a research article by Hemminki and Bermejo (2005), it is noted that if the risk factors of a cancer remain constant, an effective screening moduality should reduce disease specific mortality. In their study data was collected on age-incidence relationships and familial risk for breast cancer in various European countries with regard to the coverage of organized mammogram services. The data was used to span the periods of implementation of the nation-wide mammographic screening programs.
The study also examined the familial grouping of breast cancer between sisters. The results indicated an assumption could be made that sisters of a newly diagnosed sister would actively seek screening and other medical advice and affect the bias of the study (Hemminki, et al. , 2005). Hemminki et al. reported some evidence was found to support the existence of such a bias in the groups of women in the study when the first sister was diagnosed and uncontrollable variables, such as family size add some uncertainty to clinical risk estimation.
It was concluded that clustering of cancer in family members may be an indication of a heritable disease and that up until now the screening and diagnostic methods have not appreciably distorted familial risk for breast cancer (Hemminki, 2005). Risk Assessment Models The literature indicates that as research in risk assessment of women at risk for breast cancer grows, healthcare providers are using two common models for risk assessment. The Gail risk assessment model and the Claus model are the most common models used to predict a woman’s risk of breast cancer (Ozanne, et al. , 2006).
The Gail Model is a statistical model designed by researchers at the National Cancer Institute and the National Surgical Adjuvant Breast and Bowel Project as a tool for health care providers (Komen web site). Risk factors used in this model include age, age at menarche, age at first live birth, number of first-degree relatives with breast cancer (mother, sister or daughter), number of breast biopsies and the results of the biopsies (Ozanne, 2006). The Claus model estimates the probability that a woman will develop breast cancer based on her family history of breast cancer (Ozanne, 2009).
This model was developed from the Cancer and Steroid Hormone (CASH) population-based, case control study involving 4730 patients with histologically documented breast cancer and 4688 matched controls (Ozanne, 2006). Hereditary and Health Belief Models The model used to predict patients who are Breast Cancer (BRCA) gene mutation carriers is the Hereditary model. This model is available for use clinically for women with a positive family history of breast cancer, it cannot be used for women without a family history of the disease (Ozanne, 2006).
The Health Belief Model, based on the premise that an individual’s perception of susceptibility can provide impetus for behavioral change, predicts that women who know they have a family history of breast cancer, particularly in a first-degree relative, might be motivated to become more aware of their risk compared to other women (Myers et al. , 2008). Healthcare providers must sort through the models and medical evidence to help their patients at high risk for breast cancer. A shared decision making process in which the doctor and patient share information and values is a collaborative process (Silvia, et al. , 2008).
Breast cancer risk assessment coupled with risk communication counseling enable the identification of women at risk for breast cancer, yet it also demands an understanding of how women at increased risk understand information about their specific risk, the interventions available to them and how these factors influence their decision-making (Ozanne, et al. , 2009). Genetic Predispostion for Breast Cancer Several well-established factors have been associated with an increased risk of breast cancer, including family history, nullparity, early menses, advanced age, and a personal history of breast cancer (National Cancer Institute, 2011).
Researchers are trying to identify the causes of breast cancer, including the gene changes or variations in addition to changes in autosomal dominant transmitted genes Breast Cancer susceptibility gene 1 (BRCA1) and Breast Cancer susceptibility gene 2 (BRCA2), both mutations are known predisposers for both breast and ovarian cancer 3(National Cancer Institute, 2011). BRCA1 and BRCA 2 belong to a class of genes known as tumor suppressors. A person who inherits a mutated or “changed” BRCA1/BRCA2 gene has a higher risk of getting breast, ovarian or prostate cancer (NCCN
Guidelines for Patients, 2010). Women with these mutations have a 55%-87% lifetime risk for breast cancer and a 20%-65% lifetime risk for ovarian cancer (Ozanne et al. , 2006, p. 111). Women with breast cancer before age 55 who carry an inherited mutation BRCA1 or BRCA2 are four times more likely to develop cancer in the breast opposite to their intial tumor as compared to breast cancer patients without the BRCA1/BRCA2 defects (Malone, Kathleen et al Journal of Clinical Oncology NCCN April 5, 2010).
Malone reports their international, multi-center study, coordinated by Memorial Sloan Kettering Cancer Center, analyzed data from 705 women with breast cancer in both breasts and a comparison group of 1,398 women with cancer in only one breast (all women had been first diagnosed before age 55). “This is the first and largest population-based study to date of these two important breast cancer susceptibility genes and their relation to contralateral breast cancer risk,” (Malone). This study provides the clearest picture yet of the prevalence and risk of contralateral breast cancer among women in the general population who carry mutations in BRCA1 and BRCA2. ” Genetic testing remains unavailable to many women because of the high costs and the fear of asking for insurance authorization (Ozanne et al. , 2006). Genetic Information Nondiscrimination Act (GINA) passed in 2008 and prohibits discrimination based on genetic information in relation to health insurance and employment but the law does not cover life insurance, disability insurance and long-term care insurance (National Human Genome Research Institute, 2011).
Evidence based Recommendations Considerable debate continues over many specific issues regarding the screening of women with a family history of breast cancer, including which screening test to use and at what age surveillance should begin (Bennett et al. , 2010). The components of breast screening evaluation are dependent on patient age and other factors such as medical and family history, physical examination, risk assessment and outcome of studies such as mammogram and MRI’s (American Cancer Institute).
The National Comprehensive Cancer Network (NCCN) Clinical Practice Guidelines in Oncology provides a 50 page report for health care providers to utilize when screening and treating all women for breast cancer. The NCCN provides two categories; women at normal risk and women at increased risk. The increased risk consists of six groups: (1) women who have previously received therapeutic thoracic irradiation or mantle irradiation; (2) women 35 years or older with a 5-year risk of invasive breast carcinoma greater than or equal to 1. %; (3) women with a lifetime risk of breast cancer >20% based on models largely dependent on family history; (4) women with a strong family history of genetic predisposition; (5) women with lobular carcinoma in situ or atypical hyperplasia; and (6) women with a prior history of breast cancer (NCCN Breast Cancer Screening and Diagnosis, 2011). Current Screening Protocol The National Cancer Institute’s (NCI) recommendation for screening mammograms includes: • Women age 40 and older should have mammograms every 1 to 2 years. Women who are at higher than average risk of breast cancer should talk with their health care providers about when and how often prior to age 40. (NCI, 2011) The American College of Obstetricians and Gynecologist (ACOG) recommend the following guidelines for providers: • Screening mammogram every 1-2 years for women aged 40-49 • Screening mammogram every year for women age 50 and older • Breast Self Exam (BSE) (ACOG, 2011). Healthcare providers are encouraged to be judicial when choosing breast screening guidelines for their patients. Scott A. Pierson, M. D. board-certified medical oncologist and hematologist, specializes in treating breast cancer in women. Dr. Pierson reports it is recommended by oncologist that the National Comprehensive Cancer Network Guidelines be followed when primary providers screen and treat their patinets (personal communication September 23, 2011). Lowe (2010), Professor at the University of Colorado Health Sciences Center School of Nursing and editor of the Journal of Obstetric, Gynecologic & Neonatal Nurses, notes concerns related to the U. S. Preventive Services Task Force (USPSF) statement regarding screening for breast cancer.
Lowe states “many women and health care providers may be confused and concerned about these new guidelines, particularly those who have faithfully complied with the former screening recommendations” (p. 134). Getting a high-quality screening mammogram and having a clinical breast exam done by a healthcare provider on a regular basis are the most effective ways to detect breast cancer early (National Cancer Institute Fact Sheet, 2010) Evidence-based practice is continually researched in medicine; having the latest guidelines for providers is essential in their decisions to diagnose and treat breast cancer.
Efficacy of Various Screening Modalities Breast cancer screening is performed in asymptomatic women so that disease can be detected and treated as early as possible. Early detection of breast cancer with screening mammography means that treatment can be started earlier in the course of the disease, hopefully before it has spread (Leach, 2008). Results from randomized clinical trials and other studies show that screening mammography can help reduce the number of deaths from breast cancer among women ages 40 to 74, especially for those over age 50 (U.
S. Department of Health and Human Services, 2010). Bennett, Muller, Cockburn, Joshua, Thorley, Baker, Wood, Brazier, Jones, Dunn and Gattas (2010), conducted a study of a multimodality screening program at the Familial Breast Cancer Screening clinics. Participants included women 30 years of age. The clinical study was started in 1999 and since its inception 2440, women have participated. A total of 7051 breast-screening examinations were completed on the 2440 participants. Bennett et. l concluded that multimodality screening, which included clinical breast examinations, ultrasound and mammograms, for women at high risk for familial breast cancer is effective and appropriate, with very acceptable cancer detection rates and pathologic cancer characteristics observed by the clinicians in the early stages of the cancers (2010). Trop, LaLonde, Mayrand, David, Larouche and Provencher (2010) conducted a study examining multimodality breast cancer screening in women with a familial or genetic predisposition to breast cancer.
They evaluated the performance of mammography, ultrasound and magnetic resonance imaging (MRI). The study enrolled 184 women, and 387 screening rounds were performed. For each screening the imaging tests were independently interpreted by three radiologists. The results indicated that in high-risk women, MRI offered the best sensitivity for breast cancer screening. MRI findings should be correlated with clinical history, physical examination and the results of mammography. Table 1 provides guidelines for annual MRI surveillance (Leach, 2008). |Table 1.
Annual MRI Surveillance should be offered to: | |Known BRCA or BRCA2 mutation carriers between ages of 35 and 49 | |Known TP53 mutation carriers aged 20 and older | |Women aged between 30 and 39 years with a 10 year risk >8% | |Women between 40 and 49 years with a 10 year risk >20%, or with a 10 year risk >12% and mammographically dense breasts | |Women who have not been tested but are at a high risk of carrying a BRCA1 or TP53 genetic mutation and are aged 30-49 who have a | |50% risk of carrying such a mutation in a tested family, or a 50% change of carrying such a mutation in an untested or | |inconclusively tested family with at least a 60% chance of carrying one of these mutations, equivalent to a 30% chance of | |themselves carrying such a mutation. | |(Leach, 2008) | Methods The National Cancer Institute conducts and supports ongoing breast cancer research ranging from basic science through the full spectrum of clinical care (National Cancer Institute, 2010). Researchers are trying to identify the causes of breast cancer.
Scientists are investigating how hormonal, dietary, and environmental factors might contribute to the development of breast cancer (NHI, 2010). An excellent way to obtain information about a particular group of people is with survey research; therefore, surveys are frequently used in our society (Cottrell & McKenzie, 2011). A Questionnaire design begins with an understanding of the capabilities of the questionnaire and how it will help your research (Questionairre Design, 2011). Questionnaires are versatile, allowing the collection of both subjective and objective data through the use of open or closed format questions to fit the medium (The Survey System, 2011).
Telephone interviews enable a researcher to gather information rapidly (Research Methods Knowledge Base, 2011). Like personal interviews, they allow for some personal contact between the interviewer and the respondent. And, they allow the interviewer to ask follow-up questions. With a busy clinical practice the interviewer would need to be cognizant of time when speaking with healthcare providers and/or their staff. ……Sinicrope et al. , (2008) conducted an exploratory study to explore adult daughter’s reports of breast cancer reduction advice received from their mothers. Data was collected by telephone interview on 94. 6% of eligible participants; 70. 3% participated, 14. 9% refused and 6. 9% were unable to be contacted after several attempts (2008).
After the telephone interview participants were sent pre-addressed stamped envelopes with each questionnaire discussed in the phone interview. Summary The literature reflects that women at high risk for breast cancer face challenging decisions often heightened by the high level of information they receive. Risk assessment and risk communication counseling enables providers to identify risk factors for all women. Although breast cancer information about risk and prevention is abundant, physicians and patients may not be aware of the efficacy of the modalities available. Physicians play a critical role in providing accurate evidence-based guidance in screening methods to their patients. Genetic testing can be costly and is often not understood by patients.
Genetic counseling can only occur if physicians refer a patient. A dedicated team of professionals is important in screening and diagnosing breast cancer in high risk women. The National Cancer Institute and the National Comprehensive Cancer Network encourages preventive care, information giving and good communication as well as evidence-based practice from all healthcare professionals involved in breast cancer care. Assessing providers level of awareness of what is recommended for breast cancer screening in high risk patients will be beneficial to not only the provider but also the patient. References Bennett, I. C. , Muller, J. , Cockburn, L. Joshua, H. , Thorley, G. , Baker, C. , Wood, N. , Brazier, J. , Jones, M. , Dunn, N. , & Gattas, M. (2010). Outcomes of multimodality breast screening women at increased risk of familiar breast cancer. World Journal of Surgery, 34, 979-986. doi: 10. 1007/s00268-010-0409-4 Glasziou, P. , & Houssami, N. (2011). The evidence base for breast cancer screening. Preventive Medicine, 53, 100-102. doi: 10. 1016/j. ypmed. 2011. 05. 011 Hemminki, K. , & Bermejo, J. L. (2005). Effects of screening for breast cancer on its age- incidence relationships and familial risk. International Journal of Cancer, 117, 145- 149. Leach, M. O. (2008).
Breast cancer screening in women at high risk using MRI. NMR Biomedicine, 22, 17-27. doi: 10. 1002/nbm. 1326 Lowe, N. K. (2010). What’s a woman to do about the new breast and cervical cancer screening recommendations? Journal of Obstetric, Gynecologic & Neonatal Nursing, 39, 133-134. doi:10. 111/j. 1552-6909. 2010. 01099. x Mathieu, E. , Barratt, A. L. , McGeechan, K. , Davey, H. M. , Howard, K. , & Houssami, N. (2010). Helping women make choices about mammography screenings; an online randomized trial of a decision aid for 40 year old women. 81 (1), 63-72. doi: 10. 16/j. pec2010. 01. 001 Myers, C. D. , Jacobsen, P. B. , & Huang, Y. (2008).
Familial and perceived risk of breast cancer in relation to use of complementary medicine. Cancer Epidemiology, Biomarkers & Prevention, 17, 1527-1534. doi: 10. 1158/1055-9965. EPI-08-0028 National Cancer Institute, General Information About Breast Cancer, Fact Sheet for Breast Cancer, 2010. Retrieved from: National Human Genome Research Institute http:///www. cancer. gov/cancertopics/pdq/treatment/breast/healthprofessionalht tp://www. genome. gov/24519851 National Comprehensive Cancer Network, Breast Cancer Screening and Diagnosis Retrieved from: http://www. nccn. org/professionals/physician_gls/pdf/breast-screening. pdf Ozanne, E. M. Klemp, J. R. , & Esserman L. J. (2006). Breast cancer risk assessment and prevention: a framework for shared decision-making consultations. The Breast Journal, 12 (2), 103-113. Ozanne, E. M. , Wittenberg, E. , Garber, J. E. , & Weeks, J. C. (2009). Breast cancer prevention: patient decision making and risk communication in the high risk setting. The Breast Journal, 16 (1), 38-47. doi: 10. 111/j. 1524-4741. 2009. 00857. x Sinicrope, P. S. , Patten, C. A. , Clark, L. P. , Brockman, T. A. , Frost, M. H. , Petersen, L. R. , Vierkant, R. A. , Vachon, C. M. , Frederickson, Z. S. , Janney, C. A. , Sellers, T. A. , & Cerhan, J. R. (2009).
Adult daughters’ reports of breast cancer risk reduction and early detection advice received from their mothers; an exploratory study. Psycho- Oncology, 18, 169-178. doi: 10. 1002/pon. 1393 Susan G. Komen, Risk Factors and Prevention; Risk Assessment Tool Retrieved from: http://ww5. komen. org/Content. aspx? id=6932 Trop, I. , Lalonde, L. , Mayrand, M. H. , David, J. , Larouche, N. , & Provencher, D. (2010). Multimodality breast cancer screening in women with a familial or genetic predisposition. Current Oncology, 17 (3), 28-36. Retrieved from: Research Methods Knowledge Base http://www. ncbi. nlm. nih. gov/pmc/articles/PMhttp://www. socialresearchmethods. n
