A predictive model using MRI and clinicopathologic features for breast cancer recurrence in young women treated with upfront surgery.

OBJECTIVES: To identify preoperative breast MR imaging and clinicopathological variables related to recurrence and develop a risk prediction model for recurrence in young women with breast cancer treated with upfront surgery. METHODS: This retrospective study analyzed 438 consecutive women with breast cancer aged 35 years or younger between January 2007 and December 2016. Breast MR images before surgery were independently reviewed by breast radiologists blinded to patient outcomes. The clinicopathological data including patient demographics, clinical features, and tumor characteristics were reviewed. Univariate and multivariate logistic regression analyses were used to identify the independent factors associated with recurrence. The risk prediction model for recurrence was developed, and the discrimination and calibration abilities were assessed. RESULTS: Of 438 patients, 95 (21.7%) developed recurrence after a median follow-up of 65 months. Tumor size at MR imaging (HR = 1.158, p = 0.006), multifocal or multicentric disease (HR = 1.676, p = 0.017), and peritumoral edema on T2WI (HR = 2.166, p = 0.001) were identified as independent predictors of recurrence, while adjuvant endocrine therapy (HR = 0.624, p = 0.035) was inversely associated with recurrence. The prediction model showed good discrimination ability in predicting 5-year recurrence (C index, 0.707 in the development cohort; 0.686 in the validation cohort) and overall recurrence (C index, 0.699 in the development cohort; 0.678 in the validation cohort). The calibration plot demonstrated an excellent correlation (concordance correlation coefficient, 0.903). CONCLUSION: A prediction model based on breast MR imaging and clinicopathological features showed good discrimination to predict recurrence in young women with breast cancer treated with upfront surgery, which could contribute to individualized risk stratification. CLINICAL RELEVANCE STATEMENT: Our prediction model, incorporating preoperative breast MR imaging and clinicopathological features, predicts recurrence in young women with breast cancer undergoing upfront surgery, facilitating personalized risk stratification and informing tailored management strategies. KEY POINTS: Younger women with breast cancer have worse outcomes than those diagnosed at more typical ages. The described prediction model showed good discrimination performance in predicting 5-year and overall recurrence. Incorporating better risk stratification tools in this population may help improve outcomes.

Use of a commercial artificial intelligence-based mammography analysis software for improving breast ultrasound interpretations.

OBJECTIVES: To evaluate the use of a commercial artificial intelligence (AI)-based mammography analysis software for improving the interpretations of breast ultrasound (US)-detected lesions. METHODS: A retrospective analysis was performed on 1109 breasts that underwent both mammography and US-guided breast biopsy. The AI software processed mammograms and provided an AI score ranging from 0 to 100 for each breast, indicating the likelihood of malignancy. The performance of the AI score in differentiating mammograms with benign outcomes from those revealing cancers following US-guided breast biopsy was evaluated. In addition, prediction models for benign outcomes were constructed based on clinical and imaging characteristics with and without AI scores, using logistic regression analysis. RESULTS: The AI software had an area under the receiver operating characteristics curve (AUROC) of 0.79 (95% CI, 0.79-0.82) in differentiating between benign and cancer cases. The prediction models that did not include AI scores (non-AI model), only used AI scores (AI-only model), and included AI scores (integrated model) had AUROCs of 0.79 (95% CI, 0.75-0.83), 0.78 (95% CI, 0.74-0.82), and 0.85 (95% CI, 0.81-0.88) in the development cohort, and 0.75 (95% CI, 0.68-0.81), 0.82 (95% CI, 0.76-0.88), and 0.84 (95% CI, 0.79-0.90) in the validation cohort, respectively. The integrated model outperformed the non-AI model in the development and validation cohorts (p < 0.001 for both). CONCLUSION: The commercial AI-based mammography analysis software could be a valuable adjunct to clinical decision-making for managing US-detected breast lesions. CLINICAL RELEVANCE STATEMENT: The commercial AI-based mammography analysis software could potentially reduce unnecessary biopsies and improve patient outcomes. KEY POINTS: • Breast US has high rates of false-positive interpretations. • A commercial AI-based mammography analysis software could distinguish mammograms having benign outcomes from those revealing cancers after US-guided breast biopsy. • A commercial AI-based mammography analysis software may improve interpretations for breast US-detected lesions.

Effects of Preoperative Breast MRI on Breast Cancer Survival Outcomes in Women Aged 35 Years and Younger.

Background The impact of preoperative breast MRI on the long-term outcomes in patients with breast cancer who are 35 years and younger has not been established. Purpose To evaluate the impact of preoperative breast MRI on recurrence-free survival (RFS) and overall survival (OS) in women with breast cancer who are 35 years and younger by using propensity score matching. Materials and Methods A total of 708 women who were 35 years and younger (mean age, 32 years ± 3 [SD]) and diagnosed with breast cancer from 2007 to 2016 were retrospectively identified. Patients who underwent preoperative MRI (MRI group) were matched with those who did not (no MRI group) according to 23 patient and tumor characteristics. RFS and OS were compared using the Kaplan-Meier method. Cox proportional hazards regression analysis was used to estimate the hazard ratios (HRs). Results Of 708 women, 125 patient pairs were matched. In the MRI group versus the no MRI group, the mean follow-up time was 82 months ± 32 versus 106 months ± 42, and the rates of total recurrence and death were 22% (104 of 478 patients) versus 29% (66 of 230 patients) and 5% (25 of 478 patients) versus 12% (28 of 230 patients), respectively. The time to recurrence was 44 months ± 33 in the MRI group and 56 months ± 42 in the no MRI group. After propensity score matching, the MRI and no MRI groups did not show significant differences in total recurrence (HR, 1.0; P = .99), local-regional recurrence (HR, 1.3; P = .42), contralateral breast recurrence (HR, 0.7; P = .39), or distant recurrence (HR, 0.9; P = .79). The MRI group showed a tendency toward better OS, but this was not statistically significant (HR, 0.47; P = .07). In the entire unmatched cohort, MRI was not an independent significant factor for predicting RFS or OS. Conclusion Preoperative breast MRI was not a significant prognostic factor for recurrence-free survival in women 35 years and younger with breast cancer. A tendency toward better overall survival was observed in the MRI group, but this was not significant. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Kim and Moy in this issue.

Improving mammography interpretation for both novice and experienced readers: a comparative study of two commercial artificial intelligence software.

OBJECTIVES: To evaluate the improvement of mammography interpretation for novice and experienced radiologists assisted by two commercial AI software. METHODS: We compared the performance of two AI software (AI-1 and AI-2) in two experienced and two novice readers for 200 mammographic examinations (80 cancer cases). Two reading sessions were conducted within 4 weeks. The readers rated the likelihood of malignancy (range, 1-7) and the percentage probability of malignancy (range, 0-100%), with and without AI assistance. Differences in AUROC, sensitivity, and specificity were analyzed. RESULTS: Mean AUROC increased in both novice (0.86 to 0.90 with AI-1 [p = 0.005]; 0.91 with AI-2 [p < 0.001]) and experienced readers (0.87 to 0.92 with AI-1 [p < 0.001]; 0.90 with AI-2 [p = 0.004]). Sensitivities increased from 81.3 to 88.8% with AI-1 (p = 0.027) and to 91.3% with AI-2 (p = 0.005) in novice readers, and from 81.9 to 90.6% with AI-1 (p = 0.001) and to 87.5% with AI-2 (p = 0.016) in experienced readers. Specificity did not decrease significantly in both novice (p > 0.999, both) and experienced readers (p > 0.999 with AI-1 and 0.282 with AI-2). There was no significant difference in the performance change depending on the type of AI software (p > 0.999). CONCLUSION: Commercial AI software improved the diagnostic performance of both novice and experienced readers. The type of AI software used did not significantly impact performance changes. Further validation with a larger number of cases and readers is needed. CLINICAL RELEVANCE STATEMENT: Commercial AI software effectively aided mammography interpretation irrespective of the experience level of human readers. KEY POINTS: • Mammography interpretation remains challenging and is subject to a wide range of interobserver variability. • In this multi-reader study, two commercial AI software improved the sensitivity of mammography interpretation by both novice and experienced readers. The type of AI software used did not significantly impact performance changes. • Commercial AI software may effectively support mammography interpretation irrespective of the experience level of human readers.

Oncologic outcomes of immediate breast reconstruction in young women with breast cancer receiving neoadjuvant chemotherapy.

BACKGROUND: Oncologic safety of postmastectomy breast reconstruction in young women with breast cancer is not well-defined, especially in the setting of neoadjuvant chemotherapy (NACT). We retrospectively compared the oncologic outcomes following nipple-sparing (NSM)/skin-sparing mastectomy (SSM) with immediate breast reconstruction (IBR) and conventional mastectomy (CM) alone in young breast cancer patients after NACT. METHODS: A total of 1266 women with primary breast cancer who underwent NACT followed by total mastectomy with or without IBR were reviewed. Of these, only young patients (age ≤ 40 years at diagnosis) were included in the outcome analysis (n = 375). After propensity score-matching by clinical T and N stage, molecular subtype, response to NACT, and adjuvant radiotherapy status, 228 patients were 1:1 matched, comprising balanced IBR group (with NSM/SSM) and CM-alone group. RESULTS: The 5-year locoregional recurrence-free, disease-free, distant metastasis (DM)-free, and breast cancer-specific survival (BCSS) rates for the entire cohort of young patients were 83.4%, 65.3%, 71.7%, and 85.4%, respectively. Locoregional recurrence rates between the matched groups were similar (14% vs. 15.8%; p = 0.710); however, IBR group had significantly lower DM rate (27.2% vs. 40.4%; p = 0.036) and breast cancer mortality (14.9% vs. 27.2%; p = 0.023) than CM-alone group. IBR group showed significantly improved 5-year DM-free survival (74.1% vs. 62.6%; p = 0.043) and BCSS (89.1% vs. 77.6%; p = 0.048) rates than CM-alone group. CONCLUSIONS: Our results indicated that IBR with NSM/SSM does not negatively affect long-term oncologic outcomes compared to CM alone in young women with breast cancer receiving NACT.

Preoperative Breast MRI in Women 35 Years of Age and Younger with Breast Cancer: Benefits in Surgical Outcomes by Using Propensity Score Analysis.

Background The role of preoperative MRI in women 35 years of age or younger with breast cancer remains controversial. Purpose To determine the association between preoperative MRI and surgical outcomes in women aged 35 years or younger with breast cancer by using propensity score (PS) analysis to investigate the impact of preoperative MRI. Materials and Methods Women 35 years of age or younger diagnosed with breast cancer between 2007 and 2017 who had or had not undergone preoperative breast MRI were retrospectively identified. The MRI detection rate of additional suspicious lesions was analyzed, and changes in surgical management were recorded. Inverse probability weighting (IPW) and PS matching were used to adjust 19 variables and to create a balance between the two groups. Surgical outcomes were compared by using univariable logistic regression. Results Among 964 women (mean age ± standard deviation, 32 years ± 3), 665 (69%) had undergone preoperative MRI (MRI group; mean age, 32 years ± 3) and 299 (31%) had not (no-MRI group; mean age, 32 years ± 3). In the MRI group, additional suspicious lesions were found in 178 of the 665 women (27%), with 88 of those 178 women (49%) having malignant lesions. The surgical management was changed in 99 of the 665 women (15%) due to MRI findings, which was appropriate for 62 of those 99 women (63%). In the IPW analysis, the MRI group showed lower odds of repeat surgery (odds ratio [OR], 0.13; 95% CI: 0.07, 0.21; P < .001) and higher odds of initial mastectomy (OR, 1.62; 95% CI: 1.17, 2.25; P = .004). However, there was no difference in the overall mastectomy rate (OR, 1.24; 95% CI: 0.91, 1.68; P = .17) compared with the no-MRI group. These results were consistent when using the PS matching method. Conclusion Preoperative MRI in young women with breast cancer is useful for detecting additional malignancy and improving surgical outcomes by reducing the repeat surgery rate, with a similar likelihood of overall mastectomy. © RSNA, 2021 Online supplemental material is available for this article.

Association of mammography and ultrasound features with MammaPrint in patients with estrogen receptor-positive, HER2-negative, node-positive invasive breast cancer.

BACKGROUND: MammaPrint is a 70-gene signature microarray assay that predicts the likelihood of recurrence of breast cancer and chemotherapeutic benefits. PURPOSE: To investigate the association between mammography and ultrasound (US) features and MammaPrint results in patients with estrogen receptor (ER)-positive, HER2-negative, node-positive invasive breast cancer, and to identify the predictive factors for high risk of recurrence. MATERIAL AND METHODS: This retrospective study included 251 patients with ER-positive, HER2-negative, 1-3 node-positive invasive breast cancer. Mammography and US findings were reviewed according to the BI-RADS criteria. The association between MammaPrint results and the clinicopathological and imaging features was evaluated. Logistic regression analysis was performed to identify independent predictors for high risk of recurrence. RESULTS: Of the patients, 143 (57.0%) and 108 (43.0%) had low and high risks for recurrence on MammaPrint, respectively. Young age (odds ratio [OR] 1.08; 95% confidence interval (CI) 1.04-1.12; P<0.001), posterior enhancement on US (OR 2.45; 95% CI 1.16-5.20; P = 0.019), absence of posterior shadowing on US (OR 3.19; 95% CI 1.17-8.62; P = 0.023), high histologic grade (OR 113.36; 95% CI 6.79-1893.53; P = 0.001), and high Ki-67 level (OR 4.90; 95% CI 2.62-9.17; P<0.001) were independently associated with high risk of recurrence on multivariate logistic regression analysis. CONCLUSION: Posterior features in US may predict a high risk of recurrence in patients with ER-positive, HER2-negative, node-positive invasive breast cancer, which may be useful in enhancing the diagnostic value of MammaPrint and aid in the decision-making process regarding treatment.

Analysis of false-negative findings of breast cancer on previous magnetic resonance imaging.

BACKGROUND: Despite the excellent contribution of contrast-enhanced breast magnetic resonance imaging (MRI), there are variable false-negative cases on MRI. PURPOSE: To evaluate the false-negative findings of breast cancer on previous MRI. MATERIAL AND METHODS: Between 2012 and 2016, we collected 132 patients who underwent surgery for a second primary cancer and had both current and previous MRI at an interval of <3 years. We included 45 patients; we excluded 38 patients who could not find a second cancer in the previous MRI and 49 patients who had a second cancer near to the original cancer and within within the same quadrant. Compared with current MRI, we retrospectively assessed the second primary cancer on previous MRI according to BI-RADS and analyzed the reasons of misinterpretation. RESULTS: Analysis of previous MRI revealed 26 (57.8%) masses (mean size 7.7 ± 2.25 mm), 12 (26.7%) non-mass enhancements (mean size 14.7 ± 4.76 mm), and 7 (15.5%) foci. At first reading, 24 (53.3%) were missed, 17 (37.8%) were assessed as BI-RADS category 2 or 3, and 4 (8.9%) were assessed as category 4. On current MRI, 39 (86.7%) lesions showed an increase in size and 22 (48.9%) showed a change in kinetics to wash-out pattern. CONCLUSION: On previous MRI, missed or misinterpreted cancers show variable findings of mass and non-mass enhancements with any types of kinetics. Careful application of BI-RADS is necessary as well as an appropriate biopsy. Any lesion that increases in size and changes in kinetics should not be underestimated.

Added Value of the Vascular Index on Superb Microvascular Imaging for the Evaluation of Breast Masses: Comparison With Grayscale Ultrasound.

OBJECTIVES: To evaluate the value of the vascular index (VI) on Superb Microvascular Imaging (SMI; Canon Medical Systems Corporation, Tokyo, Japan) in comparison with grayscale ultrasound (US) alone for assessing breast masses. METHODS: We evaluated a total of 70 breast masses (36 malignant and 34 benign lesions) in 70 consecutive patients using grayscale US and SMI. Two breast radiologists analyzed grayscale US alone and the combination of grayscale US and SMI. They also measured the VI based on SMI. The diagnostic performance of grayscale US alone and the combination of grayscale US and SMI was compared. The VI was compared between benign and malignant masses, and the optimal cutoff value was determined. In addition, the interobserver agreement in imaging analyses and the VI was assessed. RESULTS: The interobserver agreements in imaging analyses and the VI were almost perfect. The VI of malignant breast masses was significantly higher than that of benign lesions (P < .001). The optimal cutoff value of the VI for differentiating between malignant and benign breast masses was 2.95, with sensitivity of 86.1% and specificity of 91.2%. The diagnostic performance values of grayscale US alone and the combination of grayscale US and SMI were 0.824 and 0.912, respectively, for reader 1 (P = .028) and 0.795 and 0.853 for reader 2 (P = .101). CONCLUSIONS: The VI on SMI was significantly higher for malignant breast masses than for benign lesions, with high interobserver agreement. Our study suggests that the combination of grayscale US and SMI with the VI could improve the characterization of breast masses.

Surgical Outcomes for Ductal Carcinoma in Situ: Impact of Preoperative MRI.

Background The role of preoperative MRI for predicting surgical outcomes in patients diagnosed with ductal carcinoma in situ (DCIS) remains uncertain. Purpose To investigate the associations between preoperative MRI and surgical outcomes in DCIS confirmed by using US-guided core-needle biopsy (CNB) and to evaluate clinical-pathologic variables associated with a benefit from MRI. Materials and Methods Women with DCIS confirmed by using US-guided CNB between January 2012 and December 2016 were included in this retrospective study. Propensity score matching using 18 confounding covariates was used to create matched groups with MRI and without MRI, and surgical outcomes were compared. Clinical-pathologic variables were evaluated to determine women who benefited from MRI. Results A total of 541 women (mean age ± standard deviation, 50 years ± 10) were evaluated. Among 430 women who underwent MRI, 67 additional lesions (16%) were depicted, with 25 (37%) of the 67 additional lesions being malignant. Fifty-seven (13%) of the 430 women had a change in surgical plan because of their MRI findings; the change was appropriate for 31 (54%) women. In matched groups, the MRI group was associated with lower odds of positive resection margin (odds ratio [OR], 0.39; 95% confidence interval [CI]: 0.16, 0.93; P = .03) and repeat surgery (OR, 0.33; 95% CI: 0.12, 0.92; P = .03) compared with the non-MRI group. There was no difference in likelihood of initial mastectomy (OR, 1.2; 95% CI: 0.7, 2.0; P = .59) and overall mastectomy (OR, 0.93; 95% CI: 0.5, 1.6; P = .79). In the MRI group, low nuclear grade (90% [28 of 31] vs 69% [275 of 399]; P = .01), progesterone receptor positivity (81% [25 of 31] vs 61% [244 of 399]; P = .03), and human epidermal growth factor receptor 2 negativity (90% [28 of 31] vs 68% [270 of 399]; P = .01) were associated with a benefit from MRI versus no MRI. Conclusion Preoperative MRI depicted additional malignancy and reduced positive surgical margins and repeat surgery for ductal carcinoma in situ confirmed at US-guided biopsy without a higher mastectomy rate. © RSNA, 2020 Online supplemental material is available for this article. See also the editorial by Pinker in this issue.

Male patients with unilateral breast symptoms: an optimal imaging approach.

OBJECTIVES: To evaluate the usefulness of bilateral mammography in male patients with unilateral breast symptoms, including investigation of the diagnostic performance of unilateral and bilateral reviews and the average glandular dose (AGD) per exposure. METHODS: Two hundred seventy-one consecutive male patients (mean age, 57 years) with unilateral breast symptoms underwent bilateral mammography. Image interpretation was performed in two ways, first with a unilateral review of the symptomatic breast and then with a bilateral review. A modified BI-RADS scale (from 1 to 5) was used. The diagnostic performance of unilateral and bilateral reviews was compared, and contralateral breast abnormalities and the AGD per exposure were recorded. We also analyzed ultrasound (US) results and compared them with mammography. RESULTS: Of 271 male patients, 29 were pathologically diagnosed with breast cancer. There was no bilateral breast cancer. The sensitivity, specificity, positive and negative predictive values, and accuracy were 96.6%, 96.7%, 77.8%, 99.6%, and 96.7%, respectively, for unilateral review, and 96.6%, 95.9%, 73.7%, 99.6%, and 95.9% for bilateral review. Receiver operator characteristic analysis showed excellent diagnostic performance for both methods: the area under the curve (AUC) was 0.966 for unilateral review and 0.962 for bilateral review (p = 0.415). The mean AGD per exposure was 1.10 ± 0.29 mGy for symptomatic breast and 1.04 ± 0.30 mGy for contralateral breast (p < 0.001). Diagnostic performance parameters of US were not significantly different from bilateral or unilateral review of mammography. CONCLUSION: The diagnostic performance of unilateral mammography is comparable with bilateral mammography in male patients with unilateral breast symptoms. Unilateral mammography also has the advantage of reducing radiation exposure. KEY POINTS: • There is limited knowledge about standardized guidelines or recommendations for imaging the male breast. • Unilateral mammography for male patients with unilateral breast symptoms showed comparable diagnostic performance with bilateral mammography. • Both unilateral and bilateral mammography showed excellent diagnostic performance in the assessment of male patients with unilateral breast symptoms.

The role of MRI and clinicopathologic features in predicting the invasive component of biopsy-confirmed ductal carcinoma in situ.

BACKGROUND: The upgrade rate of biopsy-confirmed ductal carcinoma in situ (DCIS) to invasive carcinoma is up to 50% on final pathology. We investigated MRI and clinicopathologic predictors of the invasive components of DCIS diagnosed by preoperative biopsy and then compared MRI features between patients with DCIS, microinvasive ductal carcinoma (mIDC), and invasive ductal carcinoma (IDC) diagnosed on final pathology. METHODS: Two hundred and one patients with 206 biopsy-confirmed DCIS lesions were enrolled. MRI and clinicopathologic features were used to predict either mIDC or IDC via a cumulative logistic regression analysis. For the lesions detected on MRI, morphologic and kinetic analyses were performed using the Chi-square, Fisher's exact, and Kruskal-Wallis tests. RESULTS: Of all the lesions, 112 (54.4%) were diagnosed as DCIS, 50 (24.3%) were upgraded to mIDC, and 44 (21.4%) to IDC. The detection on MRI as mass (Odds ratio (OR) = 8.84, 95% confidence interval (CI) = 1.05-74.04, P = 0.045) or non-mass enhancement (NME; OR = 11.17, 95% CI = 1.35-92.36, P = 0.025), negative progesterone receptor (PR; OR = 2.40, 95% CI = 1.29-4.44, P = 0.006), and high Ki-67 level (OR = 2.42, 95% CI = 1.30-4.50, P = 0.005) were significant independent predictors of histologic upgrade. On MRI, 87 (42.2%) lesions appeared as mass and 107 (51.9%) as NME. Irregularly shaped, not-circumscribed, heterogeneous, or rim-enhancing masses with intratumoral high signal intensity or peritumoral edema, clumped or clustered ring-enhancing NMEs, and high peak enhancement were significantly associated with histologic upgrade (P < 0.001). CONCLUSION: MRI detection, negative PR, and high Ki-67 levels are associated with a histologic upgrade in patients with biopsy-confirmed DCIS. Suspicious MRI features are more frequent in such patients.

Diagnostic performance of standard breast MR imaging compared to dedicated axillary MR imaging in the evaluation of axillary lymph node.

BACKGROUND: Breast magnetic resonance (MR) imaging does not usually assess axillary lymph nodes -using dedicated axillary sequence. The additional utility of dedicated axillary sequence is poorly understood. We evaluated the diagnostic performance of dedicated axillary imaging sequence for evaluation of axillary lymph node. METHODS: In this retrospective study from January 2018 to March 2018, 750 consecutive women underwent breast MR imaging. 263 patients were excluded, due to neoadjuvant chemotherapy (n = 235), incomplete histopathological information (n = 14) and follow-up loss (n = 14), 487 women were included. Two radiologists scored lymph node on confidence level scale from 0 (definitely benign) to 4 (definitely malignant), -using standard MR and dedicated axillary imaging sequences. Diagnostic performance parameters were compared and calculated correlation coefficient of quantitative features (largest dimension, cortical thickness, and the ratio of cortical thickness to largest dimension of lymph node). RESULTS: 68 (14.0%) were node-positive and 419 (86.0%) were node-negative. The sensitivity, specificity, positive, negative predictive values and accuracy were respectively, 66.2, 93.3, 61.6, 94.4, and 89.5% for dedicated axillary sequence and 64.7, 94.0, 63.8, 94.3, 89.9% for standard MR sequence The dedicated axillary and standard sequences s did not exhibit significant differences in detection of positive lymph nodes (AUC, 0.794 for standard and 0.798 for dedicated axillary sequence, P = 0.825). The cortical thickness appeared to be the most discriminative quantitative measurement using both axillary (AUC, 0.846) and standard sequences (AUC, 0.823), with high correlation coefficient (0.947). CONCLUSION: Evaluation of axillary nodal status using standard breast MR imaging is comparable to dedicated axillary MR imaging.

Mammography, US, and MRI to Assess Outcomes of Invasive Breast Cancer with Extensive Intraductal Component: A Matched Cohort Study.

Background An extensive intraductal component (EIC) in breast cancer is an independent risk factor for local recurrence after surgery, especially in young, premenopausal women. Few studies have analyzed long-term outcomes or imaging features of EIC-positive breast cancer. Purpose To assess the prognostic value of EIC on recurrence-free and overall survival in breast cancer and evaluate imaging features of EIC-positive breast cancer by using mammography, US, and MRI. Materials and Methods A retrospective study of 6816 consecutive women with surgically diagnosed invasive breast cancer between January 2007 and December 2012 was performed. After individual matching, women were allocated into either an EIC-positive or an EIC-negative group. Imaging factors associated with prognosis were investigated. The recurrence-free and overall survival rates were compared. Univariable and multivariable analyses were performed to analyze the effect of EIC. Results Among 6136 included women (mean age, 48.9 years ± 9.8), 1800 EIC-positive and 4336 EIC-negative breast cancers were identified. After matching according to EIC presence was performed, 1551 women were allocated into each group. The mean follow-up period was 79.9 months. The local-regional recurrence rate in the EIC-positive group was higher than that in the EIC-negative group (39.4% [63 of 160] vs 25.5% [37 of 145]; P = .001). However, there were no significant differences in total recurrence rate (hazard ratio [HR]: 1.2; 95% confidence interval [CI]: 0.9, 1.4; P = .21) or death (HR: 1.1; 95% CI: 0.8, 1.5; P = .45). EIC was not a significant independent factor for recurrence-free survival (HR: 1.1; 95% CI: 0.9, 1.4; P = .45) or death (HR: 1.1; 95% CI: 0.8, 1.6; P = .44) in multivariable analyses. Calcification and non-mass lesions were more commonly seen at US and MRI in the EIC-positive group than in the EIC-negative group (P < .001). Conclusion The presence of an extensive intraductal component in women with invasive breast cancer did not affect overall survival or recurrence-free survival. © RSNA, 2019 Online supplemental material is available for this article. See also the editorial by Eby in this issue.

Long-term survival outcomes in invasive lobular carcinoma patients with and without preoperative MR imaging: a matched cohort study.

OBJECTIVE: To investigate and compare the effect of preoperative breast magnetic resonance (MR) imaging on recurrence-free survival (RFS) and overall survival (OS) outcomes among patients with invasive lobular carcinoma (ILC). METHODS: A total of 287 ILC patients between January 2005 and December 2012 were included. One hundred twenty (41.8%) had undergone preoperative breast MR imaging (MR group) and 167 (58.2%) had not (no MR group). Two groups were matched for 21 covariates in terms of patient demographics, tumor characteristics, and clinical features. We compared unmatched variables between the patients with and without breast MR imaging using the chi-square or Student's t test. Comparisons of matched data were performed with McNemar's test or test of symmetry for categorical variables and paired t test for continuous variables. The RFS and OS outcomes were compared using the Kaplan-Meier estimates. MR effects were estimated after adjusting for significant potential confounders of specific outcomes in the multivariable modeling. RESULTS: In the matched cohort, no statistically significant association was observed between MR imaging and total recurrence (hazard ratio [HR], 1.096; p = 0.821), loco-regional recurrence (HR, 1.204; p = 0.796), contralateral breast recurrence (HR, 0.945; p = 0.952), or distant recurrence (HR, 1.020; p = 0.973). MR imaging was associated with improved OS with 51% reduction, but not significantly (HR, 0.485; p = 0.231). Analysis with multivariable Cox regression model indicated that MR imaging was not significant independent factor for better RFS (HR, 0.823; p = 0.586) or improved OS (HR, 0.478; p = 0.168). CONCLUSION: Preoperative MR imaging is not significant prognostic factor and produces no apparent recurrence or survival outcome benefits in ILC patients. KEY POINTS: • Preoperative breast MR imaging in invasive lobular carcinoma was associated with a better overall survival with 51% reduction, but not statistically significant. • Preoperative breast MR imaging does not show significant prognostic value in invasive lobular carcinoma as there is no apparent benefit in terms of recurrence or survival outcomes.

Decrease in interpretation time for both novice and experienced readers using a concurrent computer-aided detection system for digital breast tomosynthesis.

OBJECTIVES: To compare the diagnostic performance and interpretation time of digital breast tomosynthesis (DBT) for both novice and experienced readers with and without using a computer-aided detection (CAD) system for concurrent read. METHODS: CAD system was developed for concurrent read in DBT interpretation. In this observer performance study, we used an enriched sample of 100 DBT cases including 70 with and 30 without breast cancers. Image interpretation was performed by four radiologists with different experience levels (two experienced and two novice). Each reader completed two reading sessions (at a minimum 2-month interval), once with and once without CAD. Three different rating scales were used to record each reader's interpretation. Reader performance with and without CAD was reported and compared for each radiologist. Reading time for each case was also recorded. RESULTS: Average area under the receiver operating characteristic curve values for BI-RADS scale on using CAD were 0.778 and 0.776 without using CAD, demonstrating no statistically significant differences. Results were consistent when the probability of malignancy and percentage probability of malignancy scales were used. Reading times per case were 72.07 s and 62.03 s (SD, 37.54 s vs 34.38 s) without and with CAD, respectively. The average difference in reading time on using CAD was a statistically significant decrease of 10.04 ± 1.85 s, providing 14% decrease in time. The time-reducing effect was consistently observed in both novice and experienced readers. CONCLUSION: DBT combined with CAD reduced interpretation time without diagnostic performance loss to novice and experienced readers. KEY POINTS: • The use of a concurrent DBT-CAD system shortened interpretation time. • The shortened interpretation time with DBT-CAD did not come at a cost to diagnostic performance to novice or experienced readers. • The concurrent DBT-CAD system improved the efficiency of DBT interpretation.

Comparison of Pathologic Response Evaluation Systems After Neoadjuvant Chemotherapy in Breast Cancers: Correlation With Computer-Aided Diagnosis of MRI Features.

OBJECTIVE. The objective of our study was to compare pathologic response assessment systems with dynamic contrast-enhanced MRI (DCE-MRI) features and evaluate the predictive performance of DCE-MRI features relative to different pathologic response assessment systems after neoadjuvant chemotherapy (NAC). MATERIALS AND METHODS. This retrospective study included 223 women (mean age, 47.2 years; age range, 31-71 years) who underwent DCE-MRI before and after completing NAC before definitive surgery between January and December 2015. Six MRI features (i.e., tumor size; angio volume; peak enhancement; and persistent, plateau, and washout enhancing components) were measured and correlated with the Miller-Payne grading system, residual cancer burden (RCB) class, and modified in-breast RCB index. Percentage changes in MRI features were correlated with pathologic assessment systems using the Spearman rank correlation test; ROC curves were analyzed to predict pathologic outcomes. RESULTS. All six MRI features correlated most strongly with the in-breast RCB index (r = -0.75 to -0.51, p < 0.001) followed by the Miller-Payne system (r = 0.47-0.72, p < 0.001) and RCB class (r = -0.58 to -0.41, p < 0.001). The in-breast RCB index correlated most strongly with the angio volume reduction rate (r = -0.75, p < 0.001) followed by maximum diameter (r = -0.69, p < 0.001), peak enhancement (r = -0.67, p < 0.001), washout component (r = -0.60, p < 0.001), plateau component (r = -0.59, p < 0.001), and persistent component (r = -0.51, p < 0.001). CONCLUSION. The in-breast RCB index correlated best with changes in DCE-MRI features, and the MRI-measured angio volume reduction rate correlated best with pathologic tumor responses.

Screening mammography for second breast cancers in women with history of early-stage breast cancer: factors and causes associated with non-detection.

BACKGROUND: The aim of our study was to identify the factors and causes associated with non-detection for second breast cancers on screening mammography in women with a personal history of early-stage breast cancer. METHODS: Between January 2000 and December 2008, 7976 women with early-stage breast cancer underwent breast surgery in our institution. The inclusion criteria of our study were patients who had: (a) subsequent in-breast recurrence, (b) surveillance mammography within 1 year before recurrence. Retrospective analysis of mammography was performed. Non-detection was defined as second breast cancers that were not visible on screening mammography. Imaging features, demographics, primary breast cancer (PBC) characteristics, and clinical features were evaluated to determine its association with non-detection. Univariate and multivariate logistic regression analyses were also performed to identify the factors related to non-detection. RESULTS: We identified 188 patients that met the criteria. Among them, 39% of patients showed non-detection (n = 74). Of the 74 patients with non-detection, 53 (72%) were classified as having no detectable mammographic abnormality (i.e., true negative) due to overlapping dense breast tissue (n = 32), obscured by postoperative scar (n = 12) or difficult anatomic location / poor positioning (n = 9). The remaining 21 patients were categorized as having subtle findings (n = 11) or missed cancer (n = 10). Non-detection for second breast cancers were significantly associated with mammographic breast density (p = 0.001, OR = 2.959) and detectability of PBC on mammography (p = 0.011, OR = 3.013). CONCLUSION: Non-detection of second breast cancer in women with a personal history of early-stage breast cancer were associated with mammographic dense breast and lower detectability of PBC on mammography.

Breast MR Imaging before Surgery: Outcomes in Patients with Invasive Lobular Carcinoma by Using Propensity Score Matching.

Purpose To investigate the association between preoperative breast magnetic resonance (MR) imaging and surgical outcomes in patients with invasive lobular carcinoma (ILC) by using propensity score matching to decide whether MR examination is beneficial in the ILC subtype of breast cancer. Materials and Methods The authors identified 603 patients with ILC who underwent surgery between January 2005 and December 2016. Of the 603 patients, 369 (61.2%) underwent MR imaging. The authors calculated the MR detection rate of additional lesions that were occult at mammography and ultrasonography and analyzed any alterations in surgical management. After propensity score matching, 196 pairs of patients were allocated to the groups, and the 17 possible confounding variables regarding patient and tumor characteristics and various clinical features were well balanced between the patients who underwent MR imaging and those who did not. Surgical outcomes were compared. Results Of the 369 patients who underwent MR imaging, additional lesions were detected in 145 (39.3%); 95 of the 145 patients (65.5%) had malignant lesions. A change in surgical management occurred because of MR findings in 94 of the 369 patients (25.5%). According to pathologic findings, this change was appropriate for 84 of the 94 patients (89.4%). In the propensity score-matched analysis, breast MR imaging was associated with lower odds of repeat surgery (odds ratio, 0.140; P < .001) and similar likelihood of initial mastectomy (odds ratio, 0.876; P = .528) and final mastectomy (odds ratio, 0.744; P = .151) compared with patients without breast MR imaging. Conclusion Preoperative MR imaging is useful for detecting additional synchronous malignancy and significantly reducing the likelihood of repeat surgery without increasing the rate of mastectomy in patients with ILC. © RSNA, 2018.

Predicting the level of tumor-infiltrating lymphocytes in patients with triple-negative breast cancer: Usefulness of breast MRI computer-aided detection and diagnosis.

PURPOSE: To evaluate the usefulness of magnetic resonance imaging (MRI) computer-aided detection and diagnosis (CAD) for the detection of tumor-infiltrating lymphocytes (TILs) in triple-negative breast cancer (TNBC) patients. TNBC is a heterogeneous malignancy with a varying prognosis. Recently, the importance of TILs in TNBC has been determined. MATERIALS AND METHODS: We retrospectively enrolled 60 lesions of TNBC. Either at 1.5T or 3T MRI, including T1 , T2 -weighted, and dynamic contrast-enhanced, images were obtained. The CAD results for all lesions were obtained, and we analyzed quantitative kinetic features including the initial peak enhancement and enhancement profiles. We divided the tumors into two groups: those with a TIL level of less than 50%, and those with a TIL level of 50% or more. Kinetic parameters were compared using Student's t-tests and chi-square tests. RESULTS: There were 48 low-TIL lesions and 12 high-TIL lesions. The portion of persistent enhancement of tumors was negatively associated with the TIL levels (P = 0.003). The persistent minus washout value of the low-TIL group was higher than that of the high-TIL group (P = 0.008). The odds ratios were 0.944 (P = 0.012) for the persistent portion and 0.971 (P = 0.008) for the persistent minus washout value. CONCLUSION: The prediction model using kinetic enhancement parameters, particularly persistent proportion and plateau minus washout value, could be helpful for identifying TIL levels in TNBC and may be used as an imaging biomarker to guide the treatment plan. LEVEL OF EVIDENCE: 4 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018;47:760-766.