Evaluation of the Utility of Screening Mammography for High-Risk Women Undergoing Screening Breast MR Imaging.

Purpose To evaluate the value of mammography in detecting breast cancer in high-risk women undergoing screening breast magnetic resonance (MR) imaging. Materials and Methods An ethics-approved, retrospective review of prospective databases was performed to identify outcomes of 3934 screening studies (1977 screening MR imaging examinations and 1957 screening mammograms) performed between January 2012 and July 2014 in 1249 high-risk women. Performance measures including recall and cancer detection rates, sensitivity, specificity, and positive predictive values were calculated for both mammography and MR imaging. Results A total of 45 cancers (33 invasive and 12 ductal carcinomas in situ) were diagnosed, 43 were seen with MR imaging and 14 with both mammography and MR imaging. Additional tests (further imaging and/or biopsy) were recommended in 461 screening MR imaging studies (recall rate, 23.3%; 95% confidence interval [CI]: 21.5%, 25.2%), and mammography recalled 217 (recall rate, 11.1%; 95% CI: 9.7%, 12.6%). The cancer detection rate for MR imaging was 21.8 cancers per 1000 examinations (95% CI: 15.78, 29.19) and that for mammography was 7.2 cancers per 1000 examinations (95% CI: 3.92, 11.97; P < .001). Sensitivity and specificity of MR imaging were 96% and 78% respectively, and those of mammography were 31% and 89%, respectively (P < .001). Positive predictive value for MR imaging recalls was 9.3% (95% CI: 6.83%, 12.36%) and that for mammography recalls was 6.5% (95% CI: 3.57%, 10.59%). Conclusion Contemporaneous screening mammography did not have added value in detection of breast cancer for women who undergo screening MR imaging. Routine use of screening mammography in women undergoing screening breast MR imaging warrants reconsideration. © RSNA, 2017 Online supplemental material is available for this article.

Preoperative MRI of the breast and ipsilateral breast tumor recurrence: Long-term follow up.

BACKGROUND: Local recurrence after breast conserving surgery is reported in 5-10% of cases. This study aims to determine if preoperative MRI is associated with reduced IBTR rates in the longer term and evaluate IBTR rates of a high risk (TN and Her-2 positive) subgroup in those receiving MRI or not. METHODS: Between 1999 and 2005, patients with invasive breast cancer undergoing BCS and radiation were identified. Primary endpoint was IBTR rate. RESULTS: The cohort consisted of 470 cases: 27% underwent MRI and 73% did not. Median follow-up was 97 months. Overall 10-year IBTR rate was 3.6%. There was no significant difference in IBTR rate at 10 years between those receiving MRI or not (1.6% vs. 4.2% (P = 0.37). The TN and Her-2 positive combined subgroup had a higher IBTR rate than all others (9.8% vs. 1.7%, P = 0.001). In the group without MRI, the IBTR rate of the high risk group was 11.8% compared to 1.8% in the remainder (P = 0.002). CONCLUSION: With 10-year follow-up, there was no significant difference in IBTR rate whether preoperative MRI is performed versus not. The high risk population showed an increased IBTR rate, this was more marked in those who did not receive MRI.

Histological Grade and Immunohistochemical Biomarkers of Breast Cancer: Correlation to Ultrasound Features.

OBJECTIVES: The purpose of this study is to correlate various features of breast cancers on ultrasound to their histological grade and immunohistochemical biomarkers. METHODS: Seventy-three patients with 77 invasive breast cancers, diagnosed between August 2011 and December 2014, were included in this prospective analysis. Margin, posterior features, shape, and vascularity were determined from ultrasound and classified according to the Breast Imaging Reporting and Data System lexicon. Histological grade, estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) status (positive [+] or negative [-]) were determined from surgical pathology reports. The cancers were categorized into low grade (grades 1 or 2) and high grade (grade 3). Correlation of ultrasound features of the cancers to their histological grade and receptor status was performed. RESULTS: There were 47 low-grade and 29 high-grade cancers. There was a significant difference in margin and posterior features between the low and high grade, ER + and ER-, and PR + and PR- (all P < .05), but not between HER2 + and HER2- cancers (both P > .05). There was no significant difference in shape and vascularity among the different subtypes (all P > .05). Spiculated margin was significantly associated with low-grade, ER+, PR + status; angular margin with high grade; microlobulated margin with ER- status; shadowing with PR + status; and enhancement with high grade, ER- status (all P < .05, all odds ratios ≥ 3.94). CONCLUSIONS: There was significant association of margin and posterior features of breast cancers with their histological grade and receptor status.

Breast cancer detection among young survivors of pediatric Hodgkin lymphoma with screening magnetic resonance imaging.

BACKGROUND: Female survivors of pediatric Hodgkin lymphoma (HL) who have received chest radiotherapy are at increased risk of breast cancer. Guidelines for early breast cancer screening among these survivors are based on little data regarding clinical outcomes. This study reports outcomes of breast cancer screening with MRI and mammography (MMG) after childhood HL. METHODS: We evaluated the results of breast MRI and MMG screening among 96 female survivors of childhood HL treated with chest radiotherapy. Outcomes measured included imaging sensitivity and specificity, breast cancer characteristics, and incidence of additional imaging and breast biopsy. RESULTS: Median age at first screening was 30 years, and the median number of MRI screening rounds was 3. Ten breast cancers were detected in 9 women at a median age of 39 years (range, 24-43 years). Half were invasive and half were preinvasive. The median size of invasive tumors was 8 mm (range, 3-15 mm), and none had lymph node involvement. Sensitivity and specificity of the screening modalities were as follows: for MRI alone, 80% and 93.5%, respectively; MMG alone, 70% and 95%, respectively; both modalities combined, 100% and 88.6%, respectively. All invasive tumors were detected by MRI. Additional investigations were required in 52 patients, (54%), and 26 patients (27%) required breast biopsy, with 10 patients requiring more than 1 biopsy. CONCLUSIONS: Screening including breast MRI with MMG has high sensitivity and specificity in pediatric HL survivors, with breast cancers detected at an early stage, although it is associated with a substantial rate of additional investigations.

Diagnostic performance of quantitative shear wave elastography in the evaluation of solid breast masses: determination of the most discriminatory parameter.

OBJECTIVE: The purpose of this article is to assess the diagnostic performance of quantitative shear wave elastography in the evaluation of solid breast masses and to determine the most discriminatory parameter. SUBJECTS AND METHODS: B-mode ultrasound and shear wave elastography were performed before core biopsy of 123 masses in 112 women. The diagnostic performance of ultrasound and quantitative shear wave elastography parameters (mean elasticity, maximum elasticity, and elasticity ratio) were compared. The added effect of shear wave elastography on the performance of ultrasound was determined. RESULTS: The mean elasticity, maximum elasticity, and elasticity ratio were 24.8 kPa, 30.3 kPa, and 1.90, respectively, for 79 benign masses and 130.7 kPa, 154.9 kPa, and 11.52, respectively, for 44 malignant masses (p < 0.001). The optimal cutoff value for each parameter was determined to be 42.5 kPa, 46.7 kPa, and 3.56, respectively. The AUC of each shear wave elastography parameter was higher than that of ultrasound (p < 0.001); the AUC value for the elasticity ratio (0.943) was the highest. By adding shear wave elastography parameters to the evaluation of BI-RADS category 4a masses, about 90% of masses could be downgraded to BI-RADS category 3. The numbers of downgraded masses were 40 of 44 (91%) for mean elasticity, 39 of 44 (89%) for maximum elasticity, and 42 of 44 (95%) for elasticity ratio. The numbers of correctly downgraded masses were 39 of 40 (98%) for mean elasticity, 38 of 39 (97%) for maximum elasticity, and 41 of 42 (98%) for elasticity ratio. There was improvement in the diagnostic performance of ultrasound of mass assessment with shear wave elastography parameters added to BI-RADS category 4a masses compared with ultrasound alone. Combined ultrasound and elasticity ratio had the highest improvement, from 35.44% to 87.34% for specificity, from 45.74% to 80.77% for positive predictive value, and from 57.72% to 90.24% for accuracy (p < 0.0001). The AUC of combined ultrasound and elasticity ratio (0.914) was the highest compared with the other combined parameters. CONCLUSION: There was a statistically significant difference in the values of the quantitative shear wave elastography parameters of benign and malignant solid breast masses. By adding shear wave elastography parameters to BI-RADS category 4a masses, we found that about 90% of them could be correctly downgraded to BI-RADS category 3, thereby avoiding biopsy. Elasticity ratio (cutoff, 3.56) appeared to be the most discriminatory parameter.

Added cancer yield of breast magnetic resonance imaging screening in women with a prior history of chest radiation therapy.

BACKGROUND: Recommendation for breast magnetic resonance imaging (MRI) screening for women with a prior history of chest radiation is currently based on expert opinion, because existing data are very scant. The objective of this study was to evaluate added cancer yield of screening breast MRI in this population. METHODS: A retrospective review identified 98 women with a prior history of chest radiation therapy who had screening mammography and screening MRI performed at the authors' institution between January 2004 and July 2010. Medical records of these patients and results of 558 screening studies (296 mammograms and 262 MRI) were reviewed. Sensitivity, specificity, positive predictive value, negative predictive value, and added cancer yield were calculated. RESULTS: Malignancy was diagnosed in 13 patients, invasive cancer was diagnosed in 10 patients, and ductal carcinomas in situ was diagnosed in 3 patients. The median latency from completion of radiation to detection of the breast cancer was 18 years (range, 8-37 years). Of the 13 cancers, 12 (92%) were detected by MRI, and 9 (69%) by mammography. For mammography, the sensitivity, specificity, positive predictive value, and negative predictive value were 69%, 98%, 82%, and 95%, respectively; and, for MRI, these values were 92%, 94%, 71%, and 99%, respectively. In 4 of 98 patients, cancer was diagnosed on MRI only, resulting in an incremental cancer detection rate of 4.1% (95% confidence interval, 1.6%-10%). CONCLUSIONS: The current results indicated that MRI is a useful adjunct modality for screening high-risk women who have a prior history of chest radiation therapy, resulting in a 4.1% (4 of 98 women) added cancer detection rate. The authors concluded that both MRI and mammography should be used to screen women in this high-risk group.

Pilot study of quantitative analysis of background enhancement on breast MR images: association with menstrual cycle and mammographic breast density.

PURPOSE: To perform semiautomated quantitative analysis of the background enhancement (BE) in a cohort of patients with newly diagnosed breast cancer and to correlate it with mammographic breast density and menstrual cycle. MATERIALS AND METHODS: Informed consent was waived after the research ethics board approved this study. Results of 177 consecutive preoperative breast magnetic resonance (MR) examinations performed from February to December 2009 were reviewed; 147 female patients (median age, 48 years; range, 26-86 years) were included. Ordinal values of BE and breast density were described by two independent readers by using the Breast Imaging Reporting and Data System lexicon. The BE coefficient (BEC) was calculated thus: (SI2 · 100/SI1) - 100, where SI is signal intensity, SI2 is the SI enhancement measured in the largest anteroposterior dimension in the axial plane 1 minute after the contrast agent injection, and SI1is the SI before contrast agent injection. BEC was used for the quantitative analysis of BE. Menstrual cycle status was based on the last menstrual period. The Wilcoxon rank-sum or Kruskal-Wallis test was used to compare quantitative assessment groups. Cohen weighted κ was used to evaluate agreement. RESULTS: Of 147 patients, 68 (46%) were premenopausal and 79 (54%) were postmenopausal. The quantitative BEC was associated with the menstrual status (BEC in premenopausal women, 31.48 ± 20.68 [standard deviation]; BEC in postmenopausal women, 25.65 ± 16.74; P = .02). The percentage of overall BE was higher when the MR imaging was performed in women in the inadequate phase of the cycle (<35 days, not 7-14 days; mean BEC, 35.7) compared with women in the postmenopausal group (P = .001). Premenopausal women had significantly higher BEC when compared with postmenopausal women (P = .03). There was no significant difference in the percentage of BE between breast density groups. CONCLUSION: Premenopausal women with breast cancer, and specifically women in the inadequate phase of the cycle, presented with higher quantitative BE than postmenopausal women. No association was found between BE and breast density.

Incidence of breast cancer in patients with pure flat epithelial atypia diagnosed at core-needle biopsy of the breast.

PURPOSE: to determine the frequency of malignancy in subsequent breast excisions following core-needle biopsy (CNB) diagnosis of pure flat epithelial atypia (pFEA) and to evaluate the imaging features of the associated tumors. MATERIALS AND METHODS: Retrospective review of 8,996 image-guided CNB (2002-2010) identified 115 cases of FEA not associated with other atypia. Patients with history of breast cancer or radiation therapy were excluded. One hundred four cases (women) with pFEA (mean age 51 years, range 29-77 years) were reviewed. Stereotactic CNB was performed in 79 (76%) cases and ultrasound (US)-guided CNB in 25 (24%) cases. In 99 cases 14G needles were used, and 10G vacuum-assisted devices were used in 5 cases. Ninety-four patients had subsequent excision. Ten patients declined excision, and imaging follow-up (mean of 36 months) is available. The upgrade rate of pFEA was defined as the number of patients diagnosed with invasive carcinoma (IC) or carcinoma in situ (CIS) divided by the total number of patients. RESULTS: 10 of 104 (9.6%) patients were diagnosed with cancer: 9 presented as calcifications (89% fine pleomorphic and amorphous) and 1 case as a mammographically occult mass. The size of calcifications was not statistically significant (P=0.358). Five cases had ductal carcinoma in situ (DCIS) and five cases had IC (ductal and lobular) presenting as amorphous and pleomorphic calcifications. CONCLUSIONS: The upgrade rate of pFEA in our series was 9.6%. The presence of 4.8% of invasive cancers is substantial and warrants continuing management with surgical excision in all cases.

Imaging of fat-containing lesions of the breast: a pictorial essay.

Fat-containing breast lesions constitute a heterogeneous group of predominantly benign tumors and non-neoplastic conditions. The role of imaging is to distinguish leave-me-alone lesions from rarely occurring malignant fat-containing tumors that require histologic analysis. Correlating mammographic findings with appearance at ultrasonography often helps in identifying lesions that do not require further work-up. MRI can be valuable to confirm the presence of fat and characterize lesions indeterminate on conventional imaging. The purpose of this multimodality imaging review is to exemplify the radiologic appearances of common and uncommon fat-containing breast lesions to facilitate accurate diagnosis, avoid unnecessary interventions, and ensure appropriate management.

Accuracy of unenhanced MR imaging in the detection of axillary lymph node metastasis: study of reproducibility and reliability.

PURPOSE: To investigate the accuracy, reproducibility, and reliability of unenhanced magnetic resonance (MR) imaging techniques for detecting metastatic axillary lymph nodes in patients with newly diagnosed breast carcinoma. MATERIALS AND METHODS: Institutional review board approval and informed consent were obtained. Seventy-four consecutive women with invasive breast carcinoma were recruited to undergo preoperative breast MR imaging. Thirteen patients were excluded, two because they were undergoing preoperative chemotherapy and 11 because of the presence of movement or susceptibility artifacts on images. Thus, 61 patients (mean age, 53 years; range, 33-78 years) were included in this study. Axial T1-weighted MR images without fat saturation and diffusion-weighted (DW) MR images were analyzed by two experienced radiologists, who were blinded to the histopathologic findings. Visual and quantitative analyses of unenhanced MR images were performed. Sensitivity, specificity, and accuracy were calculated. To assess the intraobserver agreement, a second reading was performed. Statistical analysis was conducted on a patient-by-affected side basis. RESULTS: The sensitivity, specificity, and accuracy were 88%, 82%, and 85%, respectively, for axial T1-weighted MR imaging and 84%, 77%, and 80% for DW imaging. Apparent diffusion coefficients (ADCs) were significantly lower in the malignant group (P<.05 for all four readings), with the average of the four readings ranging from 0.333×10(-3) mm2/sec to 2.843×10(-3) mm2/sec. The mean Lin coefficient comparing the mean ADC reading for each observer was 0.959 (95% confidence interval: 0.935, 0.975), suggesting very high interobserver agreement between the two observers in terms of reproducibility of ADCs. The Bland-Altman plot showed good inter- and intraobserver agreement. CONCLUSION: Unenhanced MR imaging techniques showed high accuracy in the preoperative evaluation of axillary status in patients with invasive breast cancer. Results indicate reliable and reproducible assessment with DW imaging, but it is unlikely to be useful in clinical practice.

High-risk lesions diagnosed at MRI-guided vacuum-assisted breast biopsy: can underestimation be predicted?

OBJECTIVES: To evaluate the frequency of diagnosis of high-risk lesions at MRI-guided vacuum-assisted breast biopsy (MRgVABB) and to determine whether underestimation may be predicted. METHODS: Retrospective review of the medical records of 161 patients who underwent MRgVABB was performed. The underestimation rate was defined as an upgrade of a high-risk lesion at MRgVABB to malignancy at surgery. Clinical data, MRI features of the biopsied lesions, and histological diagnosis of cases with and those without underestimation were compared. RESULTS: Of 161 MRgVABB, histology revealed 31 (19%) high-risk lesions. Of 26 excised high-risk lesions, 13 (50%) were upgraded to malignancy. The underestimation rates of lobular neoplasia, atypical apocrine metaplasia, atypical ductal hyperplasia, and flat epithelial atypia were 50% (4/8), 100% (5/5), 50% (3/6) and 50% (1/2) respectively. There was no underestimation in the cases of benign papilloma without atypia (0/3), and radial scar (0/2). No statistically significant differences (p > 0.1) between the cases with and those without underestimation were seen in patient age, indications for breast MRI, size of lesion on MRI, morphological and kinetic features of biopsied lesions. CONCLUSIONS: Imaging and clinical features cannot be used reliably to predict underestimation at MRgVABB. All high-risk lesions diagnosed at MRgVABB require surgical excision.

Impact of preoperative breast MRIs on timing of surgery and type of intervention in newly diagnosed breast cancer patients.

BACKGROUND: We sought to evaluate the effect of preoperative breast magnetic resonance imaging (BMRI) on the wait time to surgery and to what extent it affects the surgical management plan initially considered. METHODS: From April 2007 to April 2009, a total of 147 newly diagnosed breast cancer patients who underwent surgery as initial treatment at Marvelle Koffler Breast Centre at Mount Sinai Hospital, Toronto, Ontario, Canada, met the inclusion criteria and were divided into two groups: those who had BMRI (n =71) and those who did not (n = 76). Time to surgery was calculated from the day core biopsy result was available to the date surgery was carried out. Time span between initial surgical consult and the day of the surgery day was also calculated. Change was defined as conversion from conservative to radical surgery and/or unilateral to bilateral procedures. RESULTS: Overall waiting period between histologic diagnosis and treatment was 34.2 days (BMRI group 36.0 days vs. non-BMRI group 32.3 days, P =0.15); and between date surgical management was propose and date of surgery (BMRI group 24.2 days vs. non-BMRI group 22.5 days, P =0.38). Additional workup resulted in seven otherwise occult malignant lesions that required change. Ten percent of patients who underwent BMRI had change in surgical management. The mastectomy rate was higher among those with preoperative BMRI (initial 12% vs. final 26%, P =0.8), but this was not statistically significant. CONCLUSIONS: Preoperative BMRI did not delay surgical treatment or correlate with a higher rate of radical treatment.

Breast Cancer Mortality among Women with a BRCA1 or BRCA2 Mutation in a Magnetic Resonance Imaging Plus Mammography Screening Program.

Annual breast magnetic resonance imaging (MRI) plus mammography is the standard of care for screening women with inherited BRCA1/2 mutations. However, long-term breast cancer-related mortality with screening is unknown. Between 1997 and June 2011, 489 previously unaffected BRCA1/2 mutation carriers aged 25 to 65 years were screened with annual MRI plus mammography on our study. Thereafter, participants were eligible to continue MRI screening through the high-risk Ontario Breast Screening Program. In 2019, our data were linked to the Ontario Cancer Registry of Cancer Care Ontario to identify all incident cancers, vital status and causes of death. Observed breast cancer mortality was compared to expected mortality for age-matched women in the general population. There were 91 women diagnosed with breast cancer (72 invasive and 19 ductal carcinoma in situ (DCIS)) with median follow-up 7.4 (range: 0.1 to 19.2) years. Four deaths from breast cancer were observed, compared to 2.0 deaths expected (standardized mortality ratio (SMR) 2.0, p = 0.14). For the 489 women in the study, the probability of not dying of breast cancer at 20 years from the date of the first MRI was 98.2%. Annual screening with MRI plus mammography is a reasonable option for women who decline or defer risk-reducing mastectomy.

Magnetic resonance imaging in the planning of initial lumpectomy for invasive breast carcinoma: its effect on ipsilateral breast tumor recurrence after breast-conservation therapy.

BACKGROUND: It remains uncertain whether routine preoperative breast magnetic resonance imaging (MRI) will lead to improved local outcomes after breast-conserving surgery (BCS) and radiation (RT) for invasive carcinoma. The purpose of this study was to determine whether MRI in the planning of the first lumpectomy reduces ipsilateral breast tumor recurrence (IBTR). METHODS: Using a prospective database, 472 initial lumpectomies from 463 women between 1999 and 2005 were examined. All patients had invasive cancer excised to negative margins on BCS, received RT, and were followed. IBTR rates were calculated by Kaplan-Meier method. Univariate and multivariate analyses were performed to investigate the association between MRI for initial lumpectomies and IBTR outcomes. RESULTS: MRI was performed before 127 (27%) lumpectomies, while 345 (73%) patients did not have a preoperative breast MRI. At median follow-up of 54 months (range 4.8-111.6 months), there was no significant difference in actuarial 8-year IBTR rates between women with preoperative MRI evaluation and women without MRI (1.8% versus 2.5%, respectively; P=0.67). After adjusting for adjuvant therapies, patient, and tumor characteristics, there continued to be no increased risk of IBTR [hazard ratio (HR) 1.7; P=0.60]. MRI visualization of tumors prior to lumpectomy did not influence the achievement of negative margins and was not associated with lower rates of re-excision (MRI: 11.8% versus no-MRI: 13.3%; P=0.50). CONCLUSION: MRI evaluation of invasive carcinoma in the planning of initial lumpectomies was not associated with improved local outcomes after BCS with RT in this cohort of patients.

Breast Background Parenchymal Enhancement on Screening Magnetic Resonance Imaging in Women Who Received Chest Radiotherapy for Childhood Hodgkin's Lymphoma.

RATIONALE AND OBJECTIVES: Breast magnetic resonance imaging (MRI) is recommended for the screening of women with a history of chest radiotherapy and consequent increased breast cancer risk. The purpose of this study was to evaluate the impact of prior chest radiotherapy on breast tissue background parenchymal enhancement (BPE) at screening breast MRI. MATERIALS AND METHODS: A departmental database was reviewed to identify asymptomatic women with either a history of chest radiotherapy for Hodgkin's lymphoma or age-matched controls who underwent screening breast MRI between 2009 and 2013. MRI studies were analyzed on an automated breast MRI viewing platform to calculate breast BPE and breast density. RESULTS: A total of 61 cases (mean age 41.6 ± 6.75 years) and 61 controls (mean age 40.8 ± 6.99 years) were included. The age of patients at the time of chest radiotherapy was 22.6 ± 8.17 years. Screening MRI was performed 19.0 ± 7.43 years after chest radiotherapy. BPE was significantly higher in patients who received chest radiotherapy (50% vs. 37%, P <0.01). A weak to moderate positive correlation (r > 0.3; P < 0.03) was found between BPE and number of years post radiotherapy. There was a trend toward significant difference between the two groups in the correlation of BPE and age (P = 0.05). Breast density was not significantly different between the two groups. CONCLUSIONS: BPE is significantly greater in women who receive chest radiotherapy for childhood Hodgkin's lymphoma, and unexpectedly, it positively correlates with the number of years passed after radiation therapy. Long-term biological effects of radiation therapy on breast parenchyma need further research.

Impact of Early Breast Cancer Screening on Mortality Among Young Survivors of Childhood Hodgkin's Lymphoma.

BACKGROUND: Female survivors treated with thoracic radiation therapy (RT) for childhood cancer experience increased risks of breast cancer (BC). There are currently no data quantifying the potential mortality gains of early BC screening among such survivors. METHODS: A mathematical model of BC development was used to evaluate the marginal benefit of early-initiated screening of female survivors of adolescent Hodgkin's lymphoma (HL) starting at age 25 years on BC mortality compared with screening initiated at age 40 years. Sensitivity analyses were performed to evaluate the robustness of the estimates over a plausible range of conditions. RESULTS: For survivors treated at age 15 years, the absolute risk of BC mortality by age 75 years was predicted to decrease from 16.65% with no early screening to 16.28% (annual mammography), 15.40% (annual MRI), 15.38% (same-day annual mammography and MRI), and 15.37% (alternating mammography and MRI every six months). Approximately 80 patients would need to be invited to MRI-based screening to prevent one BC death. In sensitivity analyses, the number needed to invite to MRI-based screening to prevent one BC death ranged from 71 to 333. Combinations of MRI plus mammography were predicted to produce 99.52 false positives per 1000 screenings done between age 25 to 39 years. CONCLUSIONS: These findings are the first to indicate that early MRI-based screening should reduce BC mortality among women treated with RT for adolescent HL. The magnitude of this benefit is superior to that described for other accepted screening indications although MRI can produce a substantial rate of false-positive results.

The value of breast MRI in high-risk patients with newly diagnosed breast cancer to exclude invasive disease in the contralateral prophylactic mastectomy: Is there a role to choose wisely patients for sentinel node biopsy?

The aim of this study was to evaluate the presence of clinically and mammographically occult disease using breast MRI in a cohort of cancer patients undergoing contralateral prophylactic mastectomy (CPM) and the utmost indication of axillary assessment (sentinel node biopsy (SLNB)) for this side. A retrospective review of patients with unilateral invasive breast cancer or ductal carcinoma in situ (DCIS) from institutional MRI registry data (2004-2010) was conducted. Characteristics of patients undergoing CPM with breast MRI obtained less than 6 month before surgery were evaluated. A total of 2322 consecutive patients diagnosed with DCIS or stage I to III infiltrating breast cancer underwent preoperative breast MRI. Of these, 1376 patients (59.2%) had contralateral clinical breast exam and mammography without abnormalities; and 116 patients (4.9%) underwent CPM (28 excluded patients had breast MRI more than 6 months before CPM). The mean age of the 88 patients was 49 years (range 28-76 years). Two (2.3%) DCIS identified on surgical pathology specimen were not depicted by MRI and the 5 mm T1N0 invasive cancer (1.1%) was identified on MRI. Preoperative MRI showed 95% accuracy to demonstrate absence of occult disease with negative predicted value (NPV) of 98% (95% CI: 91.64-99.64%). Occult disease was present in 3.4% of CPM. MRI accurately identified the case of invasive cancer in this cohort. The high negative predictive value suggests that MRI can be used to select patients without consideration of SLNB for the contralateral side.

Quantitative shear wave elastography: correlation with prognostic histologic features and immunohistochemical biomarkers of breast cancer.

RATIONALE AND OBJECTIVES: To correlate prognostic histologic features and immunohistochemical biomarkers of breast cancer with quantitative shear wave elastography (SWE) parameters. MATERIALS AND METHODS: B-mode ultrasound (US) and SWE were performed before core biopsy on 72 cancers in 68 patients. Mean cancer size was determined from US. Histologic grade, lymph node status, lymphovascular invasion (LVI), histologic type, and immunohistochemical biomarkers (estrogen receptor, progesterone receptor, human epidermal growth factor receptor 2 [HER2]) were determined from surgical pathology reports. Correlation between these features and quantitative SWE parameters (mean elasticity [E mean], maximum elasticity [E max], and elasticity ratio [E ratio]) was made. RESULTS: There was significant correlation of mean cancer size with E mean, E max, and E ratio (correlation, 0.492, 0.500, and 0.435, respectively; all P < .001). Lymph node involvement was associated with significantly higher E max (P = .040). LVI was associated with significantly higher E mean, E max, and E ratio (P = .002, .004, and .042, respectively). There was no significant correlation of histologic grade with SWE parameters. HER2+ cancers were associated with significantly higher E ratio (P = .030). In multivariate analysis, only mean cancer size was significantly correlated with E mean and E max (P < .001). CONCLUSIONS: There was significant correlation of cancer size with SWE parameters. There was significant correlation of lymph node status and LVI with SWE, but only on univariate analysis. SWE has the potential to provide prognostic information of breast cancer in a noninvasive manner, but further study is required.