«PacifiCare’s medical management guidelines represent the recommendation of the PacifiCare Medical Management Guideline (MMG) committee. They are ...»
Professional Societies/Organizations National Cancer Institute (NCI): According to the NCI, the role of MRI for breast cancer screening has not been established. There is an interest in using MRI as a screening test for high-risk women, but the benefits of MRI screening in any group of women is not yet known. The clinical role of MRI includes evaluating breast implants, assessing palpable masses following treatment, and detecting mammographically and sonographically occult breast cancer in patients with axillary node metastasis. (NCI, 2007) American College of Radiology (ACR): The ACR has established a practice guideline for the performance of magnetic resonance imaging of the breast that includes the following precautions and
indications (ACR, 2004):
- Screening breast MRI is not recommended at the current time in the general population of asymptomatic women.
- Breast MRI may detect additional abnormalities other than the clinically or mammographically detected lesions. These MRI-detected, clinically and mammographically occult lesions may or may not be clinically significant.
- Patients being considered for breast- conserving treatment may be converted to mastectomy based on MRI information. Caution should be exercised in changing management based on MRI findings alone, as most mammographically occult lesions are successfully treated with irradiation and/or chemotherapy following surgical removal of the known lesion. Additional biopsies or correlation with other clinical and imaging information should be used along with good clinical judgment.
Clinical trials are needed to determine the outcome significance of MRI detected, clinically occult disease.
ACR indications for breast MRI include the following:
- Lesion characterization: Breast MRI may be indicated when other imaging examinations, such as ultrasound and mammography, and physical examination are inconclusive for the presence of breast cancer. Breast MRI may be helpful in patients who have had previous surgery for breast cancer, to distinguish between postoperative scarring and recurrent cancer. Other conditions that may impair conventional breast imaging, such as silicone augmentation or radiographically dense breasts, may warrant breast MRI depending on the clinical findings.
- Neoadjuvant chemotherapy: Breast MRI may be employed before, during, and/or after a course of chemotherapy to evaluate chemotherapeutic response and the extent of residual disease prior to
Breast Imaging- Commercial Medical Management Guideline
- Infiltrating lobular carcinoma: Breast MRI may be indicated for evaluation of extent, multifocality, and multicentricity.
- Infiltrating ductal carcinoma: Breast MRI may be indicated in order to determine the extent of disease, particularly in breast conservation candidates.
- Axillary adenopathy, primary unknown: MRI may be indicated in patients presenting with axillary adenopathy and no mammographic or physical findings of primary breast carcinoma.
- Postoperative tissue reconstruction: Breast MRI may be indicated in the evaluation of suspected cancer recurrence in patients with tissue transfer flaps (rectus, latissimus dorsi, and gluteal) or implants.
- Silicone and non-silicone breast augmentation: Breast MRI may be indicated in the evaluation of patients with silicone implants and/or injections in whom mammography is difficult, and in patients with non-silicone implants. In these settings, breast MRI may be helpful in the diagnosis of breast cancer and in the evaluation of implant integrity and rupture.
- Invasion deep to fascia: MRI evaluation of breast carcinoma prior to surgical treatment may be indicated in both mastectomy and breast conservation candidates to define the relationship to the fascia, extension into pectoralis major, or extension into serratus anterior and intercostal muscles.
- Contralateral breast examination in patients with breast malignancy: MRI can detect unsuspected disease in the contralateral breast in at least 4 to 5% of breast cancer patients. This is often in the face of negative findings on mammography and physical examination.
- Postlumpectomy for residual disease: Breast MRI may be used in the evaluation of residual disease in patients who have not had preoperative MRI and whose pathology specimens demonstrate close or positive margins for residual disease. MRI can evaluate for multifocality and multicentricity to help determine which patients could be effectively treated by re-excision or whether a mastectomy is required due to the presence of more extensive disease.
- Surveillance of high-risk patients: Recent clinical trials have demonstrated that breast MRI can significantly improve the detection of cancer that is otherwise clinically and mammographically occult. Breast MRI may be indicated in the surveillance of women with a genetic predisposition to breast cancer. Patients should be referred for surveillance breast MRI only after genetic counseling by experts in hereditary breast cancer.
- Recurrence of breast cancer: Breast MRI may be indicated in women with a prior history of breast cancer and suspicion of recurrence when clinical and/or mammographic findings are inconclusive.
American Cancer Society (ACS): The ACS has established guidelines for breast screening with MRI as an adjunct to mammography. According to the guidelines, annual MRI screening (as an adjunct to mammography) is recommended (based on evidence from nonrandomized screening trials and
observational studies) for the following patients:
- patient tests positive for BRCA mutation,
- patient is untested, but is a first-degree relative of a BRCA carrier, and
- patient has a lifetime risk of 20 to 25% or greater of breast cancer as defined by risk models that are dependent on family history.
Breast Imaging- Commercial Medical Management Guideline
Annual MRI screening (as an adjunct to mammography) is recommended (based on expert consensus
opinion) for the following patients:
- patient had radiation to chest between 10 and 30 years of age,
- patient with Li-Fraumeni syndrome and first-degree relatives, and
- patient with Cowden and Bannayan-Riley-Ruvalcaba syndromes and first-degree relatives.
The ACS guidelines state that MRI screening is not recommended for women with less than a 15% lifetime risk of breast cancer. According to the ACS, there is insufficient evidence to recommend or against MRI screening in patients with a lifetime risk of 15 to 20% of breast cancer, lobular carcinoma in situ or atypical lobular hyperplasia, atypical ductal hyperplasia, heterogeneous or extremely dense breast on mammography, and women with a personal history of breast cancer, including ductal carcinoma insitu. (Saslow et al., 2007) National Comprehensive Cancer Network (NCCN): The NCCN Breast Cancer Clinical Practice Guidelines in Oncology state that breast MRI is an adjunct to other breast screening and should not be used in place of standard breast screening (i.e., mammography and ultrasound). (NCCN Breast Cancer Guidelines, 2008) The NCCN Breast Cancer Screening and Diagnosis Clinical Practice Guidelines in Oncology state that there is limited data supporting the use of MRI screening as an adjunct to mammography for high risk women or women with dense breast tissue. The guidelines also state that MRI can be considered as an adjunct to mammogram in women who are 25 years or older and have a strong family history or genetic predisposition to breast cancer. (NCCN Breast Cancer Screening and Diagnosis, 2007)
Magnetic Resonance Elastography of the Breast:
Searches of the medical literature revealed a paucity of peer-reviewed, published studies on the efficacy and safety of MRE. Two small feasibility studies evaluated the ability of MRE to differentiate breast cancers from normal breast tissue and benign tumors in mastectomy specimens, breast cancer patients and healthy women. (McKnight et al., 2002; Lorenzen et al., 2002) Although the MRE results showed that some breast cancers display increased tissue stiffness compared with benign tumors or normal breast tissue, there was overlap in values, and the accuracy of MRE for detection of breast cancer remains in question.
Fifteen patients with breast lesions underwent MRE and all breast cancer cases showed a good delineation to the surrounding breast tissue. The results for shear viscosity did not indicate that MRE was useful for differentiating benign from malignant lesions. (Sinkus et al., 2005) There are two ongoing trials sponsored by the National Institute of Health (NIH) to investigate the role of MRE in breast cancer management. The aims of these studies are to develop methods and devices for the enhancement of breast cancer detection and diagnosis using MRE. (NIH, 2007)
Breast Imaging- Commercial Medical Management Guideline
American Cancer Society (ACS): The ACS guidelines assign an evidence level of C for breast cancer screening with magnetic resonance elastography (preclinical data suggest possible promise, but clinical data are sparse or nonexistent; more study is needed). (Smith et al., 2003)
Based on 44 studies of scintimammography, an analysis found that for non-palpable lesions, the specificity of scintimammography was 39.2% (at a fixed 95% sensitivity). At the mean threshold of the included studies, the sensitivity was 68.7% and specificity was 84.8%. The analysis also found that in women with non-palpable lesions, the negative likelihood ratio of scintimammography was 0.41 (i.e., if a woman with a non-palpable lesion is diagnosed as having no cancer by scintimammography, her chance of having breast cancer drops from 20% to 9.3%). (AHRQ, 2006) A meta-analysis of scintimammography included 5,473 patients from studies performed since 1997.
The overall sensitivity was 85% and the specificity was 84% for single-site trial studies, and for multi-center trial studies the overall sensitivity was 85% and the specificity was 83%. (Hussain and Buscombe, 2006) Another meta-analysis evaluating scintimammography included 5,340 patients from studies published between January 1967 and December 1999. The aggregated summary estimates of sensitivity and specificity for scintimammography were 85.2% and 86.6% respectively.
The authors concluded that scintimammography may be used effectively as an adjunct to mammography when additional information is required to reach a definitive diagnosis. The authors also indicated that the role of scintimammography should be assessed on the basis of large, multicenter studies. (Liberman et al., 2003) Gommans et al. evaluated 103 women with non-palpable breast lesions detected by mammogram who underwent scintimammography before biopsy. Scintimammography had a specificity of 92.8%, a sensitivity of 82.2%, a positive predictive value of 90.2%, and a negative predictive value of 86.6%. (Gommans et al., 2007) Ninety women with lesions smaller than 2 cm were examined by scintimammography before biopsy.
Sensitivity was 29% for lesions less than 5 mm and 97% for lesions 11 mm or greater. The overall sensitivity was 85%. Scintimammography detected 8 additional mammographically occult tumors in 7 patients. (O'Connor et al., 2007)
The Society of Nuclear Medicine (SNM): The SNM has published guidelines for breast scintigraphy that indicate that further study is needed to determine the population that is most likely to benefit from this procedure. The guidelines also state that the usefulness of scintigraphy requires further study. (SNM, 2004) American Cancer Society (ACS): According to ACS guidelines, breast cancer screening with Breast Imaging- Commercial Medical Management Guideline scintimammography is not recommended. (evidence level of C - preclinical data suggest possible promise, but clinical data are sparse or nonexistent; more study is needed). (Smith et al., 2003) On its Web site, the ACS states that scintimammography is not used commonly and its usefulness is still being evaluated. (ACS, 2007) Agency for Healthcare Research and Quality (AHRQ): The AHRQ published a report developed by ECRI, titled Effectiveness of Noninvasive Diagnostic Tests for Breast Abnormalities. The report states that for every 1,000 women who had a negative scintimammography, approximately 907 women would have avoided an unnecessary biopsy, but 93 women would have missed cancers.
These numbers were for women with nonpalpable breast lesions only. (AHRQ, 2006) National Cancer Institute (NCI): According to NCI, the theoretical advantage of scintimammography is the potential to obtain staging information, but only small clinical series have been published.
(NCI, 2007) American College of Radiology (ACR): According to ACR practice guidelines, scintigraphy may be useful in helping to differentiate benign from malignant breast lesions. (ACR, 2005).
Full-Field Digital Mammography (FFDM):
A retrospective study compared the accuracy of digital versus film mammography in subgroups of the Digital Mammographic Imaging Screening Trial (DMIST) which included 49,528 women from 33 centers. The results of the study found that digital mammography performed significantly better than film for premenopausal and perimenopausal women younger than age 50 with dense breasts, but film performed non-significantly better for women 65 years of age or older with fatty breasts. (Pisano et al., 2008) The Oslo II study randomized 25,263 women to digital or screen-film mammography and reported that FFDM allowed a higher cancer detection rate than did SFM in patients age 50 to 69, although the difference did not reach statistical significance. The cancer detection rate was nearly equal for the two modalities in women age 45 to 49. (Skaane and Skjennald, 2004) According to the results of the Digital Mammographic Imaging Screening Trial (DMIST), digital mammography has some advantages compared with SFM. A total of 49,528 women presenting for screening mammography at 33 sites in the United States and Canada underwent both digital and conventional mammography. Complete data were available for 42,760 (86%) of these women.
Digital and film mammography had similar diagnostic accuracy for the overall patient cohort.