Screening for Breast Cancer: A New Approach

Lora Barke, DO

  ^*Radiologist, Radiology Imaging Associates P.C., Englewood, Colorado.
   Address correspondence to: Lora Barke, DO, Radiologist, Radiology Imaging Associates P.C., 10700 E Geddes Suite 200, Englewood, CO 80112. E-mail: Lora.Barke@riaco.com.

Disclosure: Dr Barke reports having no significant financial or advisory relationships with corporate organizations related to this activity.

ABSTRACT

Breast cancer has a considerable impact on public health in the United States, and early detection through regular screening efforts has been critical in improving long-term outcomes for individuals affected by the disease. For most women, screening recommendations include regular self breast examinations, annual clinical breast examinations, and annual screening mammography examinations beginning at the age of 40 years. For others, magnetic resonance imaging (MRI) is recommended as an additional screening tool. Effective breast cancer screening is critical to achieve consistent, early disease detection and reduce the need for unnecessary biopsies to distinguish between benign and malignant disease. Radiologic science professionals play an important role in the breast cancer screening process, and are often the only professionals that individuals encounter during their examination. Technologists should therefore have an understanding of current mammography and MRI practices, as well as the use of advanced modalities in screening applications, so that they are in a position to answer questions that arise and put their clients at ease. This article will review standard breast cancer screening modalities, risk factors that require additional screening efforts, and advanced modalities that are under development to improve the quality and utility of breast imaging.

Introduction
Despite large-scale public awareness campaigns that emphasize the value of early detection with breast self-examinations, annual clinical breast examinations, and regular diagnostic screening, breast cancer continues to have an important impact on public health in the United States. Following cardiovascular disease, cancer was the second leading cause of death in the United States in 2005, as reported by the Centers for Disease Control and Prevention.¹ Overall, cancer was responsible for 559 312 deaths in 2005, representing 22.8% of US mortality for the year.¹ Women run a high risk of developing breast cancer, and screening is critical to detect the disease early and achieve successful outcomes. Based on current incidence rates, the National Cancer Institute (NCI) estimates that 1 in 8 women in the United States will be affected by breast cancer in their lifetime.² Although the American Cancer Society (ACS) estimates that 26% of all cancer cases were due to breast cancer in 2008, only 16% of cancer deaths were attributable to breast cancer.³ The high incidence of breast cancer and possibility of successful outcomes with treatment emphasize the importance and value of screening and early detection in clinical practice.

Mammographers play a critical role in breast cancer screening. The technologist is not only the first professional that patients encounter during their mammography session, but is sometimes the only professional who has the opportunity to speak with the patient and answer any questions or concerns during the visit. This article will review mammography and magnetic resonance imaging (MRI) breast cancer screening modalities and will provide technologists with some perspectives on recent advances in the field of breast cancer screening.

The Evolution of Breast Cancer Screening: An Individualized Approach
Screening mammography is a critical modality in public health efforts to reduce the impact of breast cancer, and is the gold standard for screening purposes. One Swedish study comparing breast cancer mortality rates in eras before and after the introduction of widespread mammography screening programs reported a 40% to 45% reduction in breast cancer deaths after mammography was instituted.⁴ Although standardized screening guidelines have been notable in reducing breast cancer mortality, it is now recognized that an individualized approach to breast cancer is desirable. As a result, one of the most important advances in breast cancer screening in recent years has been an evolution to a more individualized approach to mammography and other imaging tests. This individualized approach has resulted in the use of MRI in select individuals, and sonography is also under review for breast cancer screening.

Elements of an Individualized Approach to Breast Cancer Screening
Traditionally, standard breast cancer screening guidelines recommended annual mammography, annual clinical breast examinations, and monthly self breast examinations. More recently, an individualized approach has emerged that includes these elements, as well as a consideration of specific risk factors, genetic consultations if warranted, and screening MRI studies in some patients (Figure 1). As a result, current guidelines recommend that annual screening mammography begin at age 40, or at an age of 10 years before the age of diagnosis in a first-degree relative, or 8 years after mantle radiation therapy for Hodgkin's lymphoma. Guidelines likewise recommend that mammography screening begin at 30 years of age in individuals who have high-risk BRCA1 or BRCA2 mutations.⁵

Screening versus Diagnostic Examinations
In this discussion, it is critical to clarify between screening and diagnostic breast imaging studies. Screening mammograms occur on an annual basis in individuals who have not exhibited any signs or symptoms of breast cancer disease. Meanwhile, a mammogram or other breast imaging modality becomes diagnostic when the individual does exhibit signs or symptoms of breast disease, such as a clinically suspicious palpable abnormality, focal breast pain, nipple discharge, mammographic abnormality, skin changes, or nipple retraction. A diagnostic imaging study is tailored to the specific needs of the patient based on the presenting clinical complaint. Individuals undergoing a diagnostic examination often require evaluation with both mammography and sonography.

Targeted Mammography
When patients undergoing screening mammography exhibit abnormal findings, the radiologist may request that the patient return for additional imaging. The abnormality can be imaged in a targeted fashion, including spot compression and magnification, to determine whether the finding is real or due to normal overlapping tissue. It is also critical to obtain the patient's prior mammograms for comparison. Spot compression involves a more focused area of compression, as opposed to compression of the entire breast in a typical mammogram, to obtain better views of the area of interest. Spot compression can rule out the presence of an abnormality and often results in more defined margins of any existing abnormality. Figure 2 demonstrates a spot compression image of an area of interest, with the corresponding sonography of the same area.

Image magnification is achieved by using a plate that brings the breast closer to the X-ray source during the mammography, resulting in magnification of an area of interest. Magnification is primarily used to better characterize calcifications, which could represent early findings of carcinoma.

Sonography in Screening and Diagnostic Settings
Additional imaging with breast sonography is often used in conjunction with diagnostic mammography to further investigate an area under question. Sonography can help distinguish between fluid-filled lesions and solid lesions, and allows radiologists to directly correlate the palpable area of concern with real-time imaging. It is recommended that ultrasound evaluations be performed during the same visit as the diagnostic mammographic study, so that a full report can be given to the patient at the time of the visit. Fluid-filled cysts are almost uniformly benign, whereas smooth, solid masses could be malignant and require additional evaluation to rule out cancer. Depending on the workflow of the facility, sonography studies can be ordered during the diagnostic mammography and performed during the same visit.

Communications of Findings with Patient
Screening and diagnostic mammography visits also differ in the way that results are communicated to the patient. Images obtained from a screening mammography are often interpreted after the patient has left the facility, and a letter is sent to the patient and to the referring physician with a summary of the findings. On the other hand, patients undergoing a diagnostic mammography study often receive the result of the study before they leave the office.

Advances in Mammography
Along with annual clinical breast examinations, mammography is widely recognized as the gold-standard modality for breast cancer screening. Mammography continues to improve and offers facilities a variety of options when conducting mammography screening and diagnostic services. One of the most fundamental changes in radiology has been a transition from screen-film to digital image acquisition, and clinical research in recent years has focused on the validation of digital studies in mammography and other imaging applications. There are relative advantages and disadvantages to both screen-film and digital studies, and facilities should weigh these carefully when making the decision to maintain a screen-film system or transition to digital image acquisition.

The American College of Radiology Imaging Network (ACRIN) Digital Mammographic Imaging Screening Trial (DMIST) was crucial in the radiology community's understanding of the relative value of screen-film and digital mammography in breast cancer screening. Screen-film mammography was known to have limitations in the ability to detect tumors in women with radiographically dense breasts, and the ACRIN DMIST study was conducted to determine the value of digital mammography in improving breast cancer tumor detection. The study enrolled 49 528 asymptomatic women who presented for breast cancer screening to undergo both screen-film and digital mammography. Two radiologists independently interpreted the resulting mammograms. The researchers compared the accuracy of screen-film and digital mammography by tracking the enrollees' breast cancer status after the initial screening, which was determined by breast biopsy performed within 15 months of study entry or a follow-up mammogram performed at least 10 months after study entry. Results were evaluated with a receiver-operating characteristic analysis. The authors reported a similar rate of diagnostic accuracy for both screen-film and digital mammography (P = .18) However, they noted that digital mammography was associated with significantly greater accuracy in women under the age of 50 (P = .002), women with heterogeneously dense breasts or extremely dense breasts (P = .003), and perimenopausal women (P = .002). The authors concluded that although screen-film and digital mammography demonstrated similar rates of diagnostic accuracy overall, digital mammography was more accurate in these 3 patient groups.⁶

Technologists should note that in addition to the greater diagnostic value in women who are under the age of 50, those with dense breasts, and perimenopausal women, digital mammography could offer additional advantages. For instance, digital imaging allows for streamlined, electronic image sharing and archiving capabilities. Unlike screen-film images, the reader can easily manipulate digital images to assist in results interpretation. Digital mammography also offers improved visualization in individuals with breast implants, and improved contrast resolution can be achieved with digital mammography as opposed to screen-film mammography. Finally, on average, digital mammography exposes individuals to a lower radiation dose than screen-film modalities.

Although digital mammography represents an important advance in breast imaging, screen-film mammography is still a viable modality that is more cost effective for facilities that do not have the resources to immediately transition to a digital platform. The choice between screen-film and digital mammography is an important decision for many facilities, but there are other modalities that are now being incorporated into the standard breast cancer screening algorithm and deserve greater attention in some individuals at an increased risk of developing the disease.

The Value of Breast MRI in High-Risk Individuals
Clinicians now recommend MRI in patients at a higher risk of developing breast cancer as an additional screening and diagnostic tool, and the value of MRI has been demonstrated in the clinical literature. One retrospective review assessed the value of MRI in patients at a high risk of developing breast cancer, who were defined as those who had experienced previous breast cancer; a family history of breast cancer; genetic mutations of the BRCA1 or BRCA2; a biopsy-proven diagnosis of atypia, lobular carcinoma in situ, or radial scar; or prior mantle radiation for Hodgkin's lymphoma. Records from 367 consecutive high-risk women were included in the analysis. Biopsy was recommended as the result of MRI screening in 17% of the individuals, and a diagnosis of breast cancer was made in 24% of women who underwent biopsy (4% who underwent MRI screening), which was not initially found through mammography or clinical examinations. More than half (57%) of the cancers found through MRI, and not detected with mammography, were characterized as noninvasive ductal carcinoma in situ (DCIS). The diagnostic power of MRI was especially strong in women who were at a higher risk due to family history of breast cancer. The authors stressed that the predictive value of MRI may be lower in a lower-risk population, and that MRI was associated with an additional expense and possible anxiety stemming from biopsies of MRI-detected masses that were found to be benign.⁷

Another surveillance cohort study followed 529 asymptomatic women who had a family history of breast cancer or confirmed mutations of the BRCA1 or BRCA2 oncogenes for a mean of 5.3 years to determine the relative value of screening modalities, including mammography, MRI, and sonography. The overall sensitivity of diagnostic imaging was found to be 93%, as 40 of 43 cases of breast cancer were detected through at least 1 of these modalities. The sensitivity of mammography for detecting breast cancer in this population was only 33%, whereas the sensitivity of sonography was 40%. The combination of both modalities resulted in a sensitivity of only 49%. Meanwhile, the sensitivity of MRI screening was 91%. Mammography and MRI demonstrated similar rates of specificity, which were 96.8% and 97.2%, respectively. The authors concluded that MRI might offer the ability to detect breast cancer at an earlier stage in women at high risk due to family history or the presence of BRCA mutations.⁸

Based on these and other studies, it is possible that MRI could offer a higher rate of sensitivity than mammography in detecting breast cancer in high-risk women, with sensitivity rates of 86% to 100% for MRI and only 13% to 43% for mammography.^7,8 Meanwhile, sonography has demonstrated sensitivity in the range of 16% to 50% in high-risk women. Both mammography and MRI have demonstrated high rates of specificity (91%-99% for MRI and 93%-99% for mammography), and sonography has a specificity of 80% to 96% in high-risk women.^7,8

Guidelines for Recommending Breast MRI
In clinical practice, contrast-enhanced breast MRI should be recommended as a screening tool, in addition to mammography, in patients at a high risk of developing breast cancer. Contrast-enhanced MRI also holds value as a diagnostic tool in newly diagnosed patients to determine the extent of breast cancer disease, or to check for ipsilateral or contralateral disease involvement in patients with breast cancer. Clinicians should also consider MRI in patients with an unknown primacy cancer who have experienced axillary lymph node metastatic disease, and when evaluating a patient's response to neoadjuvant chemotherapy to treat established breast cancer.

Magnetic resonance imaging may hold distinct advantages in other disease presentations, including patients with multicentric disease (Figure 3). In addition, MRI may be of value in detecting contralateral breast cancer in patients who have already been diagnosed with breast cancer affecting 1 breast (Figure 4). One study evaluated the value of MRI in detecting contralateral disease in 969 women who had been recently diagnosed with unilateral breast cancer (breast cancer in 1 breast).

Participating women had been recently diagnosed with unilateral breast cancer, and a diagnosis of MRI-detected cancer was confirmed through the results of biopsy within 12 months of study entry. Meanwhile, the absence of contralateral breast cancer was confirmed through biopsy, the absence of suspicious lesions on repeat imaging and clinical examination, or both, at 1-year follow-up. MRI-detected contralateral disease (cancer in the other breast) in 3.1% of enrollees in whom the contralateral disease was not initially detected by mammography or clinical examination. MRI was estimated to have a sensitivity of 91%, a specificity of 88%, and a 99% negative predictive value. The high specificity contrasted with low specificity with breast MRI reported in previous studies. Positive MRI findings resulted in the recommendation of a biopsy in 135 of the 969 women enrolled in the study, and 121 women underwent biopsy. Of these biopsies, 30 (24.8%) were confirmed to be associated with malignant lesions. All of the contralateral cancers detected by MRI were node-negative, and 40% were DCIS. The researchers noted that diagnostic yield, sensitivity, and negative predictive value of breast MRI were not influenced by patient factors such as breast density, or the histologic features of the initial breast cancer lesion. However, the specificity of MRI was significantly higher in postmenopausal women than in those who were premenopausal or perimenopausal (91% vs 84%, P = .002). Likewise, the positive predictive value was significantly higher for postmenopausal women (31% vs 11%, P = .006). Overall, 96.7% of the cancers detected by MRI were classified as stage 0 or stage 1 disease. The authors of the study also noted that in patients with unilateral breast cancer, the risk of occult cancer in the contralateral breast 1 year after a negative MRI was 0.3%, a finding that could avoid unnecessary contralateral mastectomies if patients undergo appropriate MRI and mammography prior to surgery. Although MRI is not necessary in the wider screening population, this study confirmed that the modality could be useful in patients diagnosed with unilateral breast cancer to detect early cancers of the contralateral breast that can be effectively managed in conjunction with the index cancer diagnosis.⁹ In addition, the ability to achieve earlier detection of contralateral disease could help improve outcomes and reduce the long-term costs of therapy associated with breast cancer management.

Facilities offering breast MRI should note the additional requirements associated with this advanced modality. Clearly, the investment in a high-resolution MRI instrument will be needed to perform the studies. However, most importantly, the studies will need to be performed by a dedicated team of MRI technologists with specialized training in breast MRI. In addition, the resulting data and images need to be interpreted by radiologists with an expertise in breast MRI and the ability to evaluate these findings in the context of other diagnostic studies. Facilities offering breast MRI should also have the capabilities to perform MRI-guided breast biopsy. The American College of Radiology has recognized the importance of specialized facilities with highly trained staff to provide breast MRI, and is in the process of developing accreditation standards for facilities that conduct breast MRI studies.

The Role of Sonography in Breast Cancer Screening
Sonography is still under evaluation to determine its possible role as an additional tool in breast cancer screening. The ACRIN 6666 trial was conducted to compare the relative value of mammography screening alone or mammography plus sonography screening in women at a high risk of developing breast cancer. The authors predicted that sonography could help visualize small, node-negative breast cancer masses that are not found on mammography. Women (2809 total) with dense breast tissue in at least 1 quadrant were recruited to undergo mammography and physician-performed sonography breast screening from April 2004 to February 2006. Breast cancer outcomes were determined through pathology and 12-month follow-up. The diagnostic accuracy was 78% with mammography alone and increased to 91% when sonography was added to mammography (P = .003). Most of the tumors detected by sonography (92%) were invasive and had a median size of 10 mm, and 89% were classified as negative for lymph node involvement. Overall, the positive predictive value for detecting cancer in a biopsy recommended after screening ranged from 14.2% to 33% with mammography alone to 7.8% to 15.6% with mammography in addition to sonography screening. The authors cautioned that although the addition of sonography to mammography screening may hold value in women at high risk of developing the disease, the use of sonography on a regular basis in breast cancer screening will likely result in a substantial increase in false-positive findings.¹⁰

Advances in Screening Technologies
Some imaging modalities are routinely used in clinical practice in other disease states but have yet to be proven as possible tools in routine breast cancer screening. Breast digital infrared thermal imaging (DITI) has demonstrated a degree of diagnostic value when used in addition to mammography and sonography. One prospective trial reported that DITI had 97% sensitivity, 44% specificity, and 82% negative predictive value, and made a substantial additional diagnostic contribution in women with dense breast tissue.¹¹ Positron emission tomography and computed tomography are both currently used in unique breast cancer management applications, especially with the use of an 18F-fluorodeoxyglucose marker. Technologists should note that neither of these modalities is routinely used in breast cancer screening because they have not been sufficiently studied to validate their routine use. Professionals should be aware of advances that are made in expanding screening options and improving cancer detection, particularly in high-risk women.

Breast-specific γ imaging (BSGI) is also under consideration as a breast cancer screening tool to use in addition to traditional methods. A retrospective review of 146 women who had undergone BSGI and breast biopsy found that BSGI accurately identified cancer in 80 of 83 malignant tumors, with a sensitivity of 96.4%. BSGI also correctly identified 50 of 84 nonmalignant tumors as benign, resulting in a specificity of 59.5%. Overall, the positive predictive value of BSGI was 68.8%.¹² These findings are insufficient to recommend widespread BSGI as a breast cancer screening modality, but BSGI may nevertheless be useful in confirming a cancer diagnosis or providing additional diagnostic strength to a lesion that is difficult to visualize.

Other optical techniques are being developed to expand screening options for breast cancer. Diffuse optical imaging (DOI) uses near-infrared light to visualize breast tissue. In recognizing the potential for DOI and other light-based imaging techniques to represent safe, noninvasive screening and diagnostic applications, the NCI has formed the Network for Translational Research in Optical Imaging (NTROI) to advance the science of diffuse optical spectroscopy and imaging (DOSI). In particular, the NTROI is responsible for supporting the development of DOSI-based diagnostic platforms that can be used alone or in conjunction with mammography, MRI, or sonography screening. Investigators are especially hopeful that DOSI can help improve the detection of cancer in mammographically dense breast tissue, improve the ability of imaging diagnostics to distinguish between benign and malignant lesions, and improve the ability to determine the effect of neoadjuvant chemotherapy on disease progression.¹³

Although none of these modalities are routinely used for screening in routine practice, it is possible that these advanced tools may be of use in individuals who present with complex cases, require less invasive screening, or cannot be easily assessed due to dense breast tissue or other impediments. Technologists who routinely manage breast cancer screening will need to be aware of these advances as they work to adapt to a rapidly changing field of medical technology.

Recognizing Risk Factors for Breast Cancer
Multiple risk factors have been identified that increase a woman's lifetime risk of developing breast cancer. Although women are at a substantially increased risk of developing breast cancer than men, men can nevertheless develop the disease. In general, advancing age, obesity, alcohol use, and increased breast density all increase the risk of developing breast cancer. In addition, factors that affect lifetime hormone exposure, including not having had any children, early menses, late menopause, and long-term hormone replacement therapy can also increase a woman's breast cancer risk.

Mammographically Dense Breast Tissue
Dense breast tissue makes the detection of tumors with mammography difficult and therefore increases the risk for breast cancer in these patients. A series of case-control studies was conducted to better determine the extent of increased cancer risk with mammographically dense breast tissue. Investigators sought to determine the relationship between breast density, as measured in a baseline mammogram, with the risk of developing breast cancer. In comparison with women with a breast density of less than 10%, those with a baseline mammogram breast density of 75% or higher had a more than 4-fold greater risk of developing breast cancer. This increased risk was more notable in younger women who initially presented with dense breast tissue. The investigators noted that in women who were younger than the median age of 56 years, 26% of all breast cancer detected and 50% of breast cancer detected between annual screening visits were associated with breast density in 50% or more of the mammograms. This may be an important factor when evaluating individuals for additional screening studies after determining the presence of particularly dense breast tissue. As discussed earlier, digital mammography may offer a more robust screening option when compared with screen-film mammography in women with dense breast tissue. Likewise, innovative modalities such as DOSI are under investigation and may improve the ability to screen patients with dense breast tissue.¹³

Hereditary Breast Cancer Disease
In general, breast cancer has been shown to be a hereditary disease in many families. For instance, it is estimated that 1 in 50 women of Ashkenazi Jewish descent are affected by breast cancer, whereas only 1 in 500 to 1000 women in the general population develop breast cancer. As previously noted, individuals with high-risk mutations of the BRCA1 and BRCA2 oncogenes are at an increased risk of developing breast cancer, as well as ovarian cancer. It is estimated that mutations of the BRCA1 gene increase breast cancer risk by 65%, whereas mutations of the BRCA2 gene increase breast cancer risk by 45%.^14-16 These mutations also increase the risk of subsequent breast cancer cases, including contralateral breast cancer or ovarian cancer, after initial therapy for primary breast cancer.^17,18

High-Risk Screening Recommendations
The ACS has issued guidelines for the addition of MRI to standard mammography in individuals who exhibit factors that could increase their risk of developing breast cancer. These recommendations have identified a range of individuals who could benefit from the addition of MRI to mammography, including women who have documented high-risk BRCA1 or BRCA2 mutations, a first-degree relative who carries one of these high-risk mutations, those who have a calculated lifetime risk of developing breast cancer in excess of 20%, and those who received radiation therapy to the chest between the ages of 10 and 30 years. The guidelines also recommend the addition of MRI screening in individuals with Li-Fraumeni, Cowden, or Bannayan-Riley-Ruvalcaba syndromes, or a first-degree relative with one of these syndromes.¹⁷ Meanwhile, the ACS guidelines caution that insufficient evidence exists to suggest high-risk screening methodologies such as MRI in other populations. These include individuals with a lifetime risk of 15% to 20%; pathology proven, noninvasive lesions, such as lobular carcinoma in situ, atypical lobular hyperplasia, or atypical ductal hyperplasia; heterogeneously or extremely dense breasts; or a personal history of breast cancer.¹⁹

Mechanisms for Determining Risk
A variety of risk calculators have been developed to assist in determining an individual's risk of developing breast cancer. The NCI Web site offers a breast cancer risk assessment tool, available at http://www.cancer.gov/bcrisktool/, that estimates a woman's 5-year and lifetime risk of developing invasive breast cancer based on the answers to 7 questions: whether the woman has a history of DCIS or lobular carcinoma in situ; the woman's current age; her age at the time of her first menstrual period; her age at the time of her first live birth of a child; her number of first-degree relatives who experienced breast cancer; her history of any breast biopsies; and her race/ethnicity.²⁰ This calculates the patient's risk using the Gail model. The use of this model typically underestimates the patient's risk because it does not consider genetic predisposition, age of first-degree relative who experienced breast cancer, or previous radiation therapy to the chest for the treatment of Hodgkin's lymphoma, to name a few limitations. There are more robust models to consider in patients with high-risk indicators, such as the BRCAPRO tool and Claus risk tables. These and other methods are widely available and can be used by professionals to help women determine their lifetime risk of developing breast cancer, and the most appropriate screening plan based on their level of risk and other clinical factors.

Genetic Counseling for Breast Cancer Risk
Some individuals, especially those with several first-degree relatives who have experienced breast cancer, seek genetic counseling services to better determine their risk of developing cancer and their long-term strategies for screening and disease prevention. The ACS recommends genetic testing in individuals with a personal history of breast cancer before the age of 50 years; a personal history of ovarian cancer at any age; at least 2 first-degree relatives who have experienced breast cancer, including one before the age of 50 years; at least 3 first- or second-degree relatives who have experienced breast cancer at any age; a first-degree relative with bilateral breast cancer; or a male relative with a personal history of breast cancer.¹⁹

Documentation of Risk Counseling
It is important for medical providers offering breast cancer screening services, including radiologic science professionals, to maintain proper documentation of clinical recommendations made to the individuals who seek their diagnostic expertise. Concerns should be reported to the radiologist so that they can be addressed with the patient. These include concerns about individuals who are at high risk to undergo the appropriate imaging studies or whether the radiologist should likewise recommend that the individuals encourage their first-degree relatives with similar risk factors to seek regular screening for breast cancer. Radiologists should accurately document any recommendations made to the patient, and should likewise document any refusals on the individual's part to receive genetic counseling or recommended screenings. Finally, radiologists should accurately document any clinical discussions that involve the recommendation that the individual's relatives receive genetic counseling, specialized screening, or other services due to a possible increased risk of developing breast cancer.

Conclusions
Annual mammography and clinical breast examinations represent the core gold-standard tools in achieving early detection and successful treatment of breast cancer. Mammography is now being complemented by other imaging modalities, including MRI and sonography, especially in high-risk women for whom early disease detection is especially critical. Recent updates to traditional screening guidelines for breast cancer require that clinicians have a complete picture of the patient's risk for developing breast cancer, including personal and family medical histories, genetic status, history of radiation therapy, and other factors, so that advanced imaging diagnostics such as MRI can be recommended. Updated national diagnostic guidelines reflect this paradigm shift and recommend both annual mammography and annual breast MRI in individuals at a high risk of developing breast cancer. Meanwhile, genetic testing and counseling are now common in individuals known to be affected by the BRCA1 and BRCA2 mutations. As the landscape of breast cancer screening changes, radiologic technologists and other radiology professionals are challenged to assimilate new knowledge and devote time to advanced training so that facilities can offer new imaging modalities to the community. The contribution of radiologic science professionals, in particular, cannot be underestimated as they can provide high-quality patient care, as well as achieve early cancer detection through the mastery of advancements in breast imaging technology.

References
1. Kung HC, Hoyert DL, Xu JQ, Murphy SL. Deaths: Final data for 2005. National vital statistics reports; vol 56 no 10. Hyattsville, MD: National Center for Health Statistics. 2008. Available at: http://www.cdc.gov/nchs/data/nvsr/nvsr56/nvsr56_10.pdf. Accessed February 2, 2009.

2. National Cancer Institute. DevCan-Probability of developing or dying of cancer. Available at: http://srab.cancer.gov/devcan. Accessed February 2, 2009.

3. American Cancer Society. Statistics for 2008. Available at: http://www.cancer.org/docroot/STT/STT_0.asp. Accessed February 2, 2009.

4. Duffy SW, Tabár L, Chen HH, et al. The impact of organized mammography service screening on breast carcinoma mortality in seven Swedish counties. Cancer. 2002;95:458-469.

5. Fletcher SW, Elmore JG. Clinical practice. Mammographic screening for breast cancer. N Engl J Med. 2003;348:1672-1680.

6. Pisano ED, Gatsonis C, Hendrick E, et al. Diagnostic performance of digital versus film mammography for breast-cancer screening. N Engl J Med. 2005;353:1773-1783.

7. Morris EA, Liberman L, Ballon DJ, et al. MRI of occult breast carcinoma in a high-risk population. AJR Am J Roentgenol. 2003;181:619-626.

8. Kuhl CK, Schrading S, Leutner CC, et al. Mammography, breast ultrasound, and magnetic resonance imaging for surveillance of women at high familial risk for breast cancer. J Clin Oncol. 2005;23:8469-8476.

9. Lehman CD, Gatsonis C, Kuhl CK, et al. MRI evaluation of the contralateral breast in women with recently diagnosed breast cancer. N Engl J Med. 2007;356:1295-1303.

10. Berg WA, Blume JD, Cormack JB, et al. Combined screening with ultrasound and mammography vs mammography alone in women at elevated risk of breast cancer. JAMA. 2008;299:2151-2163.

11. Arora N, Martins D, Ruggerio D, et al. Effectiveness of a noninvasive digital infrared thermal imaging system in the detection of breast cancer. Am J Surg. 2008;196:523-526.

12. Brem RF, Floerke AC, Rapelyea JA, et al. Breast-specific gamma imaging as an adjunct imaging modality for the diagnosis of breast cancer. Radiology. 2008;247:651-657.

13. Tromberg BJ, Pogue BW, Paulsen KD, et al. Assessing the future of diffuse optical imaging technologies for breast cancer management. Med Phys. 2008;35:2443-2451.

14. Ford D, Easton DF, Bishop DT, et al. Risks of cancer in BRCA1-mutation carriers. Breast Cancer Linkage Consortium. Lancet. 1994;343:692-695.

15. Struewing JP, Hartge P, Wacholder S, et al. The risk of cancer associated with specific mutations of BRCA1 and BRCA2 among Ashkenazi Jews. N Engl J Med. 1997;336:1401-1408.

16. King MC, Marks JH, Mandell JB; New York Breast Cancer Study Group. Breast and ovarian cancer risks due to inherited mutations in BRCA1 and BRCA2. Science. 2003;302:643-646.

17. Metcalfe K, Lynch HT, Ghadirian P, et al. Contralateral breast cancer in BRCA1 and BRCA2 mutation carriers. J Clin Oncol. 2004;22:2328-2335.

18. Metcalfe KA, Lynch HT, Ghadirian P, et al. The risk of ovarian cancer after breast cancer in BRCA1 and BRCA2 carriers. Gynecol Oncol. 2005;96:222-226.

19. Saslow D, Boetes C, Burke W, et al. American Cancer Society guidelines for breast screening with MRI as an adjunct to mammography. CA Cancer J Clin. 2007;57:75-89.

20. National Cancer Institute. Breast cancer risk assessment tool. Available at: http://www.cancer.gov/bcrisktool/. Accessed February 2, 2009.