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.

Characteristics and risk factors of axillary lymph node metastasis of microinvasive breast cancer.

PURPOSE: To select patients who would benefit most from sentinel lymph node biopsy (SLNB) by investigating the characteristics and risk factors of axillary lymph node metastasis (ALNM) in microinvasive breast cancer (MIBC). METHODS: This retrospective study included 1688 patients with MIBC who underwent breast surgery with axillary staging at the Asan Medical Center from 1995 to 2020. RESULTS: Most patients underwent SLNB alone (83.5%). Seventy (4.1%) patients were node-positive, and the majority had positive lymph nodes < 10 mm, with micro-metastases occurring frequently (n = 37; 55%). Node-positive patients underwent total mastectomy and axillary lymph node dissection (ALND) more than breast-conserving surgery (BCS) and SLNB compared with node-negative patients (p < 0.001). In the multivariate analysis, independent predictors of ALNM included young age [odds ratio (OR) 0.959; 95% confidence interval (CI) 0.927-0.993; p = 0.019], ALND (OR 11.486; 95% CI 5.767-22.877; p < 0.001), number of lymph nodes harvested (≥ 5) (OR 3.184; 95% CI 1.555-6.522; p < 0.001), lymphovascular invasion (OR 6.831; 95% CI 2.386-19.557; p < 0.001), presence of multiple microinvasion foci (OR 2.771; 95% CI 1.329-5.779; p = 0.007), prominent lymph nodes in preoperative imaging (OR 2.675; 95% CI 1.362-5.253; p = 0.004), and hormone receptor positivity (OR 2.491; 95% CI 1.230-5.046; p = 0.011). CONCLUSION: Low ALNM rate (4.1%) suggests that routine SLNB for patients with MIBC is unnecessary but can be valuable for patients with specific risk factors. Ongoing trials for omitting SLNB in early breast cancer, and further subanalyses focusing on rare populations with MIBC are necessary.

Ovarian Suppression: Early Menopause and Late Effects.

OPINION STATEMENT: Around 90% of breast tumours are diagnosed in the early stage, with approximately 70% being hormone receptor-positive. The cornerstone of adjuvant therapy for early-stage hormone receptor-positive breast cancer is endocrine therapy, tailored according to disease stage, biological characteristics of the tumour, patient's comorbidities, preferences and age. In premenopausal patients with hormone receptor-positive breast cancer, ovarian function suppression is a key component of the adjuvant endocrine treatment in combination with an aromatase inhibitor or tamoxifen. Moreover, it can be used during chemotherapy as a standard strategy for ovarian function preservation in all breast cancer subtypes. In the metastatic setting, ovarian function suppression should be used in all premenopausal patients with hormone receptor-positive breast cancer to achieve a post-menopausal status. Despite its efficacy, ovarian function suppression may lead to several side effects that can have a major negative impact on patients' quality of life if not properly managed (e.g. hot flashes, depression, cognitive impairment, osteoporosis, sexual dysfunction, weight gain). A deep knowledge of the side effects of ovarian function suppression is necessary for clinicians. A correct counselling in this regard and proactive management should be considered a fundamental part of survivorship care to improve treatment adherence and patients' quality of life.

High-resolution diffusion-weighted MRI plus mammography for detecting clinically occult breast cancers in women with dense breasts.

PURPOSE: To compare the performance of mammography, high-resolution DW-MRI, DCE-MRI, and their combinations in detecting clinically occult breast cancer in women with dense breasts. METHOD: 544 breasts from 281 consecutive asymptomatic women with dense breasts were retrospectively identified. They underwent breast MRI for preoperative evaluation of breast cancers (n = 214) or as supplemental screening (n = 67) including DCE-MRI and DW-MRI (b values, 0 and 1000 sec/mm2; in-plane resolution, 1.1 × 1.1 mm2 and 1.3 × 1.3 mm2; section thickness, 3 mm), in addition to mammography. Three readers independently reviewed each examination on a per-breast basis. Histopathology and at least two year of imaging follow-up served as the gold standard. The sensitivities and specificities of different imaging modalities were compared using McNemar test. RESULTS: 230 of 544 breasts (42 %) had malignant lesions. The sensitivity of DW-MRI was higher than that of mammography (77.0 % vs 57.9 %; adjusted p < 0.001), but lower than that of DCE-MRI (84.8 %; adjusted p = 0.014). The specificity of DW-MRI was comparable to those of mammography (98.1 % vs 99.1 %; adjusted p > 0.999) and DCE-MRI (97.1 %; adjusted p > 0.999). DW-MRI plus mammography had a comparable sensitivity and specificity to those of DCE-MRI plus mammography (88.6 % vs 90.9 % and 97.1 % vs 96.2 %; adjusted p > 0.999 for both). CONCLUSIONS: High-resolution DW-MRI had a sensitivity higher than mammography and lower than DCE-MRI. Nevertheless, DW-MRI plus mammography showed a comparable sensitivity and specificity to DCE-MRI plus mammography for detecting clinically occult cancers in women with dense breasts.

Comparison of long-term oncological outcomes after central lumpectomy versus nipple-sparing breast-conserving surgery for centrally located breast cancer: a propensity score-matched study.

PURPOSE: To compare the oncological safety of nipple-sparing breast-conserving surgery (BCS) versus central lumpectomy for centrally located breast cancer (CLBC). METHODS: Patients who underwent BCS for CLBC at Asan Medical Center from 2007 to 2018 were reviewed retrospectively. The oncological outcomes of nipple-sparing BCS (NS-BCS) and central lumpectomy were compared using univariate and multivariate Cox regression analyses and compared again after 1:1 propensity score matching (PSM). RESULTS: The study included 306 patients who underwent NS-BCS and 106 patients who underwent central lumpectomy (median follow-up: 111 months). On multivariate analysis, central lumpectomy had a lower risk of local recurrence compared to NS-BCS, albeit without statistical significance (HR 0.14, 95% CI 0.02-1.24; p = 0.077). There was no significant difference in the risk of death (HR 0.14, 95% CI 0.01-1.68, p = 0.12). After PSM, each group had 106 patients. The 5-year and 10-year local recurrence-free survival rates were 94.2% and 92.9% for NS-BCS, and 99.1% and 99.1% for central lumpectomy, respectively (p = 0.031). There were no significant differences in overall survival, regional recurrence-free survival, or distant recurrence-free survival. Fifteen patients (4.9%) who underwent NS-BCS had ipsilateral breast tumor recurrence (IBTR), of which 40% were in the nipple-areolar complex and previous surgical sites. One patient (0.9%) who underwent central lumpectomy experienced an IBTR in a different quadrant. CONCLUSION: NS-BCS showed more local recurrence than central lumpectomy. When deciding whether to spare the nipple during BCS in CLBC, patients should be sufficiently informed about the risk of IBTR.

Implementation of BRCA Test among Young Breast Cancer Patients in South Korea: A Nationwide Cohort Study.

Purpose: To investigate the frequency of BRCA testing and related factors among young breast cancer patients (age < 40 years) in South Korea. Materials and Methods: We conducted a nationwide retrospective cohort study using data from the Health Insurance Review and Assessment claims. Newly diagnosed breast cancer patients younger than 40 were included. Annual BRCA testing ratios (number of BRCA test recipients / the number of patients undergoing breast cancer surgery in each year) were analyzed by region and health care delivery system. We investigated the location of breast cancer diagnosis and BRCA testing. Results: From January 2010 to December 2020, there were 25,665 newly diagnosed young breast cancer patients, of whom 12,186 (47.5%) underwent BRCA testing. The BRCA testing ratios increased gradually from 0.084 (154/1,842) in 2010 to 0.961 (1,975/2,055) in 2020. Medical aid (vs. health insurance) and undergoing surgery in metropolitan cities or others (vs. Seoul), general hospitals, and clinics (vs. tertiary hospitals) were associated with a lower likelihood of BRCA testing. While 97.8% of the patients diagnosed in Seoul underwent BRCA testing in Seoul, 22.9% and 29.2% of patients who were diagnosed in metropolitan areas and other regions moved to Seoul and underwent BRCA testing, respectively. Conclusion: The frequency of BRCA testing has increased over time in South Korea, with Seoul showing a particularly high rate of testing. About one-quarter of patients diagnosed with breast cancer outside of Seoul moved to Seoul and underwent BRCA testing.

Diagnostic yield of contrast-enhanced abdominal staging CT in patients with initially diagnosed breast cancer.

PURPOSE: To estimate the diagnostic yield (DY) of abdominal staging CT for detecting breast cancer liver metastasis (BCLM) in patients with initially diagnosed breast cancer and to determine the indications for abdominal staging CT. METHODS: Patients with newly diagnosed breast cancer who underwent abdominal CT as an initial staging work-up between January 2019 and December 2020 were retrospectively analyzed. DY was calculated and analyzed according to patient age, type of treatments, histologic type, histologic grade, lymphovascular invasion, Ki-67 status, hormone receptor status, subtype, and the American Joint Committee on Cancer anatomical staging. RESULTS: A total of 2056 patients (mean age, 51 ± 11 years) were included. The DY of abdominal staging CT for detecting BCLM was 1.1 % (22 of 2056). DY was significantly higher in stage III than in stage I or II cancers (3.9 % [18 of 467] vs. 0 % [0 of 412] or 0.4 % [4 of 1158], respectively, p < .001), and in human epidermal growth factor receptor-2 (HER2)-enriched cancers than in luminal or triple negative cancers (2.9 % [16 of 560] vs. 0.4 % [4 of 1090] or 0.5 % [2 of 406], respectively, p < .001). CONCLUSIONS: The DY of abdominal staging CT for detecting BCLM was low among all patients with initially diagnosed breast cancer. However, although abdominal staging CT for detecting BCLM is probably unnecessary in all patients, it can be clinically useful in patients with stage III or human epidermal growth factor receptor-2-enriched breast cancers.

Unenhanced Breast MRI With Diffusion-Weighted Imaging for Breast Cancer Detection: Effects of Training on Performance and Agreement of Subspecialty Radiologists.

OBJECTIVE: To investigate whether reader training improves the performance and agreement of radiologists in interpreting unenhanced breast magnetic resonance imaging (MRI) scans using diffusion-weighted imaging (DWI). MATERIALS AND METHODS: A study of 96 breasts (35 cancers, 24 benign, and 37 negative) in 48 asymptomatic women was performed between June 2019 and October 2020. High-resolution DWI with b-values of 0, 800, and 1200 sec/mm² was performed using a 3.0-T system. Sixteen breast radiologists independently reviewed the DWI, apparent diffusion coefficient maps, and T1-weighted MRI scans and recorded the Breast Imaging Reporting and Data System (BI-RADS) category for each breast. After a 2-h training session and a 5-month washout period, they re-evaluated the BI-RADS categories. A BI-RADS category of 4 (lesions with at least two suspicious criteria) or 5 (more than two suspicious criteria) was considered positive. The per-breast diagnostic performance of each reader was compared between the first and second reviews. Inter-reader agreement was evaluated using a multi-rater κ analysis and intraclass correlation coefficient (ICC). RESULTS: Before training, the mean sensitivity, specificity, and accuracy of the 16 readers were 70.7% (95% confidence interval [CI]: 59.4-79.9), 90.8% (95% CI: 85.6-94.2), and 83.5% (95% CI: 78.6-87.4), respectively. After training, significant improvements in specificity (95.2%; 95% CI: 90.8-97.5; P = 0.001) and accuracy (85.9%; 95% CI: 80.9-89.8; P = 0.01) were observed, but no difference in sensitivity (69.8%; 95% CI: 58.1-79.4; P = 0.58) was observed. Regarding inter-reader agreement, the κ values were 0.57 (95% CI: 0.52-0.63) before training and 0.68 (95% CI: 0.62-0.74) after training, with a difference of 0.11 (95% CI: 0.02-0.18; P = 0.01). The ICC was 0.73 (95% CI: 0.69-0.74) before training and 0.79 (95% CI: 0.76-0.80) after training (P = 0.002). CONCLUSION: Brief reader training improved the performance and agreement of interpretations by breast radiologists using unenhanced MRI with DWI.

Pregnancy After Breast Cancer in Young BRCA Carriers: An International Hospital-Based Cohort Study.

Importance: Young women with breast cancer who have germline pathogenic variants in BRCA1 or BRCA2 face unique challenges regarding fertility. Previous studies demonstrating the feasibility and safety of pregnancy in breast cancer survivors included limited data regarding BRCA carriers. Objective: To investigate cumulative incidence of pregnancy and disease-free survival in young women who are BRCA carriers. Design, Setting, and Participants: International, multicenter, hospital-based, retrospective cohort study conducted at 78 participating centers worldwide. The study included female participants diagnosed with invasive breast cancer at age 40 years or younger between January 2000 and December 2020 carrying germline pathogenic variants in BRCA1 and/or BRCA2. Last delivery was October 7, 2022; last follow-up was February 20, 2023. Exposure: Pregnancy after breast cancer. Main Outcomes and Measures: Primary end points were cumulative incidence of pregnancy after breast cancer and disease-free survival. Secondary end points were breast cancer-specific survival, overall survival, pregnancy, and fetal and obstetric outcomes. Results: Of 4732 BRCA carriers included, 659 had at least 1 pregnancy after breast cancer and 4073 did not. Median age at diagnosis in the overall cohort was 35 years (IQR, 31-38 years). Cumulative incidence of pregnancy at 10 years was 22% (95% CI, 21%-24%), with a median time from breast cancer diagnosis to conception of 3.5 years (IQR, 2.2-5.3 years). Among the 659 patients who had a pregnancy, 45 (6.9%) and 63 (9.7%) had an induced abortion or a miscarriage, respectively. Of the 517 patients (79.7%) with a completed pregnancy, 406 (91.0%) delivered at term (≥37 weeks) and 54 (10.4%) had twins. Among the 470 infants born with known information on pregnancy complications, 4 (0.9%) had documented congenital anomalies. Median follow-up was 7.8 years (IQR, 4.5-12.6 years). No significant difference in disease-free survival was observed between patients with or without a pregnancy after breast cancer (adjusted hazard ratio, 0.99; 95% CI, 0.81-1.20). Patients who had a pregnancy had significantly better breast cancer-specific survival and overall survival. Conclusions and Relevance: In this global study, 1 in 5 young BRCA carriers conceived within 10 years after breast cancer diagnosis. Pregnancy following breast cancer in BRCA carriers was not associated with decreased disease-free survival. Trial Registration: ClinicalTrials.gov Identifier: NCT03673306.

Breast density reduction as a predictor for prognosis in premenopausal women with estrogen receptor-positive breast cancer: an exploratory analysis of the updated ASTRRA study.

BACKGROUND: While the relationship between mammographic breast density reduction (MDR) and endocrine therapy efficacy has been reported in estrogen receptor (ER)-positive breast cancer, it is still unclear in premenopausal women, especially in the case of adding ovarian function suppression (OFS) to antihormone therapy. The authors investigated the impact of MDR on prognosis stratified by treatment based on the updated results of the ASTRRA trial. MATERIALS AND METHODS: The ASTRRA trial, a randomized phase III study, showed that adding OFS to tamoxifen (TAM) improved survival in premenopausal women with estrogen receptor-positive breast cancer after chemotherapy. The authors updated survival outcomes and assessed mammography before treatment and the annual follow-up mammography for up to 5 years after treatment initiation. Mammographic density (MD) was classified into four categories based on the Breast Imaging-Reporting and Data System. MDR-positivity was defined as a downgrade in MD grade on follow-up mammography up to 2 years after randomization, with pretreatment MD grade as a reference. RESULTS: The authors evaluated MDR in 944 of the 1282 patients from the trial, and 813 (86.2%) had grade III or IV MD. There was no difference in the MDR-positivity rate between the two treatment groups [TAM-only group (106/476 (22.3%)) vs. TAM+OFS group (89/468 (19.0%)); P =0.217). MDR-positivity was significantly associated with better disease-free survival (DFS) in the TAM+OFS group (estimated 8-year DFS: 93.1% in MDR-positive vs. 82.0% in MDR-negative patients; HR: 0.37; 95% CI: 0.16-0.85; P =0.019), but not in the TAM-only group ( Pinteraction =0.039). MDR-positive patients who received TAM+OFS had a favorable DFS compared to MDR-negative patients who received only TAM (HR: 0.30; 95% CI: 0.13-0.70; P =0.005). CONCLUSION: Although the proportion of MDR-positive patients was comparable between both treatment groups, MDR-positivity was independently associated with favorable outcomes only in the TAM+OFS group.

21-gene expression assay and clinical outcomes of premenopausal patients with hormone receptor-positive breast cancer.

The prognostic role of the recurrence score (RS) based on the 21-gene expression assay in premenopausal women is not well delineated, and we investigated the association of outcomes and the RS in premenopausal patients who had 21-gene expression assay at Asan Medical Center, Seoul, Korea, between June 2005 and July 2018. Invasive breast cancer-free survival (IBCFS) by STEEP version 2.0 was compared according to the RS and clinical risk factors. A total of 554 patients were included in our study and 116 patients (20.9%) had age <40 years, 238 patients (43.0%) had luminal B subtype (Ki67 ≥ 20%), and 83 patients (15.0%) had RS >25. All patients received adjuvant tamoxifen ± chemotherapy. Overall, patients with RS >25 showed trend toward worse IBCFS from multivariable analysis (adjusted HR 1.89 [95% CI: 0.95-3.73], P = .069). When comparing outcomes according to age and luminal subtypes, patients with luminal B subtype and age <40 years (n = 60) showed significantly worse outcomes compared to the others (luminal A or luminal B + age ≥40 years, n = 494; adjusted HR 2.95 [95% CI: 1.49-5.82], log-rank P < .001). Among patients with luminal B subtype and age <40 years, there was no significant association observed between IBCFS and the RS (log-rank P = .51). In conclusion, while RS >25 showed association with poor outcomes in premenopausal women, it may have less prognostic significance among those with luminal B subtype and age <40 years.

Long-term outcome in patients with nodal-positive breast cancer treated with sentinel lymph node biopsy alone after neoadjuvant chemotherapy.

PURPOSE: Sentinel lymph node biopsy (SLNB) has yet to be accepted as the standard staging procedure in node positive (cN1) breast cancer patients who had clinical complete response in the axilla (cN0) following neoadjuvant chemotherapy (NAC), due to the presumed high false negative rate associated with SLNB in such scenario. This study aimed to determine whether there is a significant difference in the axillary recurrence rate (ARR) and long-term survival in this group of patients, receiving SLNB alone versus axillary lymph node dissection (ALND). METHODS: A retrospective cohort of cN1 patients who were rendered cN0 by NAC from January 2014 to December 2018 were identified from the Asan Medical Center database. Patients' characteristics and outcomes were collected and analyzed. RESULTS: 902 cN1 patients treated with NAC and turned cN0 were identified. 477 (52.9%) patients achieved complete pathological response in the axilla (ypN0). At a median follow up of 65 months, ARR was 3.2% in the SLNB only group and 1.8% in the ALND group (p = 0.398). DFS and OS were significantly worse in patients with ALND as compared to patients with SLNB only (p = 0.011 and 0.047, respectively). We noted more patients in the ALND group had T3-4 tumor. In the subgroup analysis, we showed that in the T1-2 subgroup (n = 377), there was no statistically significant difference in DFS and OS (p = 0.242 and 0.671, respectively) between SLNB only and ALND group. CONCLUSION: Our findings suggest that cN1 patients who were converted to ypN0 following NAC may be safely treated with SLNB only.

Prediction of the MammaPrint Risk Group Using MRI Features in Women With Estrogen Receptor-Positive, HER2-Negative, and 1 to 3 Node-Positive Invasive Breast Cancer.

BACKGROUND: MammaPrint assigns chemotherapeutic benefits to patients with estrogen receptor (ER)-positive, human epidermal growth factor receptor 2 (HER2)-negative, and 1 to 3 node-positive invasive breast cancer. However, its cost and time-consuming nature limit its use in certain clinical settings. We aimed to develop and validate the prediction models for the low MammaPrint risk group using clinicopathologic and MRI features. PATIENTS AND METHODS: Overall, 352 women with ER-positive, HER2-negative, and 1 to 3 node-positive invasive breast cancer were retrospectively reviewed and assigned to development (n = 235) and validation sets (n = 117). Univariate and multivariate analyses identified features associated with the low MammaPrint risk group. The area under the receiver operating characteristic curves (AUROCs) of models based on clinicopathologic, MRI, and combined features were evaluated. RESULTS: Development set multivariate analysis showed that clinicopathologic features including low histologic grade (odds ratio [OR], 5.29; P = .02), progesterone receptor-positivity (OR, 3.23; P = .01), and low Ki-67 (OR, 6.05; P < .001) and MRI features, including peritumoral edema absence (OR, 2.24; P = .04) and a high proportion of persistent components (OR, 1.15; P = .004) were significantly associated with the low MammaPrint risk group. The AUROCs of models based on clinicopathologic, MRI, and combined features were 0.77, 0.64, and 0.80 in the development and 0.66, 0.60, and 0.70 in the validation sets, respectively. CONCLUSION: The combined model incorporating clinicopathologic and MRI features showed potential in predicting the low MammaPrint risk group, and may support decision-making in clinical settings with limited access to MammaPrint.

Age-Related Incidence and Peak Occurrence of Contralateral Breast Cancer.

Importance: Young patients with breast cancer have higher risk for developing contralateral breast cancer (CBC) and have epidemiologic characteristics different from those of older patients. Objective: To examine the incidence and peak occurrence of CBC according to age at primary breast cancer (PBC) surgery. Design, Setting, and Participants: This cohort study included patients who were diagnosed with and underwent surgery for unilateral nonmetastatic breast cancer at Asan Medical Center, Korea, between January 1, 1999, and December 31, 2013, with follow-up through December 31, 2018. Data were analyzed from December 1, 2021, through April 30, 2023. Patients were divided into 2 groups according to their age at surgery for PBC: younger (≤35 years) vs older (>35 years). Main Outcomes and Measures: The main outcomes were cumulative incidence and hazard rate of CBC in the entire study population and in subgroups divided by cancer subtype, categorized according to hormone receptor (HR) and ERBB2 status. Results: A total of 16 251 female patients with stage 0 to III breast cancer were analyzed; all patients were Korean. The mean (SD) age was 48.61 (10.06) years; 1318 patients (8.11%) were in the younger group, and 14 933 (91.89%) were in the older group. Median follow-up was 107 months (IQR, 79-145 months). Compared with the older group, the younger group had significantly higher incidence of CBC (10-year cumulative incidence, 7.1% vs 2.9%; P < .001) and higher risk (hazard ratio, 2.10; 95% CI, 1.62-2.74) of developing CBC. The hazard rate, which indicates risk for developing CBC at a certain time frame, differed according to the subtype of primary cancer. In patients with the HR+/ERBB2- subtype, the risk increased continuously in both age groups. In patients with the triple negative subtype, the risk increased until approximately 10 years and then decreased in both age groups. Meanwhile, in the HR-/ERBB2+ subtype, risk peaked earlier, especially in the younger group (1.7 years since first surgery in the younger group and 4.8 years in the older group). Conclusions and Relevance: In this cohort study, patients aged 35 years or younger with breast cancer had a higher risk of developing CBC than older patients. Moreover, young patients with the HR-/ERBB2+ subtype tended to have a shorter interval for developing CBC. These findings might be useful in guiding treatment decisions, such as contralateral prophylactic mastectomy.

Conventional versus Robot-assisted Immediate Breast Reconstruction: Reconstructive Outcome and Patient-reported Outcome Measures (PROMs).

BACKGROUND: This study compared conventional and robot-assisted mastectomy and breast reconstruction. To the best of our knowledge, this study is the first to report the results of robot-assisted mastectomy and breast reconstruction as well as a comparison of patient-reported outcomes. METHOD: A retrospective study included 473 breasts of 423 patients who underwent conventional mastectomy and breast reconstruction and 164 breasts of 153 patients who underwent robot-assisted mastectomy and breast reconstruction from July 2019 to October 2021. Demographic and oncologic data, reconstructive outcomes, and patient-reported outcomes (BREAST-Q) were evaluated. The results of implant-based and autologous breast reconstruction were separately evaluated. RESULTS: Skin necrosis requiring surgical debridement occurred significantly more frequently in the conventional group (8.0%) than in the robot-assisted group (2.0%) in implant-based reconstruction (p=0.035). At 6-12 months, robot-assisted breast reconstruction showed a higher sexual wellbeing score for implant-based reconstruction and a higher physical wellbeing score for autologous breast reconstruction than conventional breast reconstruction according to the BREAST-Q questionnaire. CONCLUSION: Robot-assisted mastectomy and breast reconstruction was associated with less skin necrosis and better patient-reported outcomes (sexual wellbeing for implant-based reconstruction and physical wellbeing for autologous breast reconstruction) than the conventional option. Robotic surgery could be a good option for mastectomy and breast reconstruction.

Assessing internal mammary lymph node metastasis by breast magnetic resonance imaging in breast cancer.

The internal mammary lymph nodes (IMLNs) are a main pathway of metastasis in breast cancer, and breast magnetic resonance imaging (MRI) plays an important role in staging that disease. We investigated the MRI parameters that can predict metastatic IMLNs and evaluated their diagnostic performance by comparing the breast MRI findings for metastatic and benign IMLNs. From January 2016 to December 2020, 474 cases of enlarged IMLNs on breast MRI were identified. By cytopathology or integrated positron emission tomography/computed tomography (PET/CT), 168 IMLNs were confirmed as metastatic, and 81 were confirmed as benign. Breast MRIs were reviewed by 2 radiologists, and various parameters (node axes, fatty hilum, necrosis, margin characteristics, restricted diffusion, and involved levels; primary tumor location and skin involvement) were assessed. Independent t-tests, receiver operating characteristic (ROC) curve analyses, chi-square tests, and Fisher exact tests were performed to compare and evaluate the diagnostic accuracy of the imaging findings. Significant differences in the breast MRI findings for the short and long axes, fatty hilum, necrosis, margin characteristics, diffusion restriction, and tumor location were observed between benign and metastatic IMLNs. Compared with the long axis and the ratio of the axes, the short axis had the best diagnostic value (higher area under the ROC curve) for predicting metastatic IMLNs. In conclusion, breast MRI parameters such as short axis, presence of fatty hilum, necrosis, margin characteristics, and diffusion restriction can be used to evaluate and differentiate benign from metastatic IMLNs, offering valuable insights to improve diagnosis and treatment planning in breast cancer.

Factors in Parenting Stress in Young Patients With Breast Cancer and Implications for Children's Emotional Development: The PSYCHE Study.

Importance: The number of patients with breast cancer who have children is substantial. However, the emotional burden of this disease and its implication for childhood development remain largely unknown. Objective: To investigate the clinical factors in parenting stress in mothers with breast cancer and the association of maternal depression and parenting stress with their children's emotional development. Design, Setting, and Participants: This cross-sectional study involved a survey of females with stage 0 to 3 breast cancer and was conducted from June 2020 to April 2021 in Seoul, South Korea. Participants were aged 20 to 45 years and completed the Center for Epidemiologic Studies Depression-Revised scale and basic questionnaires on demographic and clinical characteristics. Participants with children completed the Korean Parenting Stress Index Short Form (K-PSI-SF), Child Behavior Checklist, Junior Temperament and Character Inventory, and Children's Sleep Habits Questionnaire. Exposure: Having children in patients with breast cancer. Main Outcomes and Measures: Multivariable logistic and linear regression analyses were performed to investigate the association between maternal depression and parenting stress. Results: A total of 699 females (mean [SD] age, 39.6 [4.6] years) were included, of whom 499 had children (mean [SD] age of children, 8.0 [2.7] years). Depression was more common in patients with children (odds ratio [OR], 2.25; 95% CI, 1.01-5.05) and patients who had gonadotropin-releasing hormone treatment (OR, 1.68; 95% CI, 1.15-2.44). Disease duration was inversely associated with depression (OR, 0.85; 95% CI, 0.76-0.96). Cancer-related factors were not associated with the K-PSI-SF score. Having children aged 6 years or older (ß = 3.09; 95% CI, 0.19-5.99); being the sole primary caregiver (ß = -3.43; 95% CI, -5.87 to -0.99); and reporting certain temperament (eg, novelty seeking: ß = 0.58; 95% CI, 0.46-0.71), emotional problems (eg, anxious/depressed: ß = 8.09; 95% CI, 3.34-12.83), and sleeping pattern (eg, bedtime resistance: ß = 0.57; 95% CI, 0.15-0.99) subscale scores in their children were associated with parenting stress. Depression and parenting stress were correlated (ß = 0.56; 95% CI, 0.45-0.66; P < .001). The emotional challenges encountered by children of mothers with breast cancer were not significantly different from reference values. Conclusions and Relevance: This study found that in patients with breast cancer, child-related factors and depression were significantly associated with parenting stress, but breast cancer-related factors were not correlated. The findings suggest that mothers with breast cancer are susceptible to both depression and parenting stress and that tailored counseling and support are needed.

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.

Survival Outcomes in Premenopausal Patients With Invasive Lobular Carcinoma.

Importance: The disparate prognostic implications between invasive ductal carcinoma (IDC) and invasive lobular carcinoma (ILC) have been demonstrated. However, information on premenopausal patients remains insufficient. Objective: To examine long-term survival outcomes of ILC and IDC in premenopausal patients using national databases. Design, Setting, and Participants: This cohort study used the Surveillance, Epidemiology, and End Results (SEER), Korean Breast Cancer Registry (KBCR), and Asan Medical Center Research (AMCR) databases to identify premenopausal patients with stage I to III ILC or IDC between January 1, 1990, and December 31, 2015. The median follow-up time was 90 (IQR, 40-151) months in the SEER database, 94 (IQR, 65-131) months in the KBCR database, and 120 (IQR, 86-164) months in the AMCR database. Data were analyzed from January 1 to May 31, 2023. Main Outcomes and Measures: The primary outcome was breast cancer-specific survival (BCSS), which was analyzed according to histological type, and the annual hazard rate was evaluated. Survival rates were analyzed using a log-rank test and a Cox proportional hazards regression model with time-varying coefficients. Multivariable analysis was performed by adjusting for tumor characteristics and treatment factors. Results: A total of 225 938 women diagnosed with IDC or ILC and younger than 50 years were identified. Mean (SD) age at diagnosis was 42.7 (5.3) years in the SEER database, 41.8 (5.5) years in the KBCR database, and 41.8 (5.5) years in the AMCR database. In terms of race (available for the SEER database only), 12.4% of patients were Black, 76.1% were White, 11.0% were of other race (including American Indian or Alaska Native, Asian, and Native Hawaiian or Other Pacific Islander), and 0.5% were of unknown race). Patients with ILC had better BCSS in the first 10 years after diagnosis than those with IDC (hazard ratios [HRs], 0.73 [95% CI, 0.68-0.78] in the SEER database, 1.20 [95% CI, 0.91-1.58] in the KBCR database, and 0.50 [95% CI, 0.29-0.86] in the AMCR database), although BCSS was worse after year 10 (HRs, 1.80 [95% CI, 1.59-2.02] in the SEER database, 2.79 [95% CI, 1.32-5.88] in the KBCR database, and 2.23 [95% CI, 1.04-4.79] in the AMCR database). Similar trends were observed for hormone receptor-positive tumors (HRs, 1.55 [95% CI, 1.37-1.75] in the SEER database, 2.27 [95% CI, 1.01-5.10] in the KBCR database, and 2.12 [95% CI, 0.98-4.60] in the AMCR database). Considering the annual hazard model of BCSS, IDC events tended to decline steadily after peaking 5 years before diagnosis. However, the annual peak event of BCSS was observed 5 years after diagnosis for ILC, which subsequently remained constant. Conclusions and Relevance: These findings suggest that premenopausal women with ILC have worse BCSS estimates than those with IDC, which can be attributed to a higher late recurrence rate of ILC than that of IDC. Histological subtypes should be considered when determining the type and duration of endocrine therapy in premenopausal women.

Multidisciplinary Shared Decision Making for Fertility Preservation in Young Women With Breast Cancer.

PURPOSE: Fertility preservation (FP) is an important issue for young survivors of breast cancer. Although international guidelines recommend pre-treatment fertility counseling for women with breast cancer, there is no standardized protocol or referral system for FP in South Korea. There are also barriers to discussing FP that make patient-centered decision making difficult. This study aimed to develop a shared decision making program for FP and compare the rates of FP procedures between the usual care and shared decision making groups. We hypothesized that multidisciplinary shared decision making for FP would increase the rate of FP procedures and patient satisfaction. METHODS: The multidisciplinary shared decision making for FP in young women with breast cancer (MYBC) is a multicenter, clustered, stepped-wedge, randomized trial. A total of 1100 patients with breast cancer, aged 19-40 years, from nine hospitals in South Korea, will be enrolled. They will be randomized at the institutional level and assigned to usual care and shared decision making groups. Four institutions, each of which can recruit more than 200 patients, will each become a cluster, whereas five institutions, each of which can recruit more than 50 patients, will become one cluster, for a total of five clusters. The shared decision making groups will receive multidisciplinary programs for FP developed by the investigator. The primary outcome is the rate of FP procedures; secondary outcomes include fertility results, satisfaction, and quality of life. Outcomes will be measured at enrollment, treatment initiation, and the 1-, 3-, and 5-year follow-ups after starting breast cancer treatment. DISCUSSION: A multidisciplinary shared decision making program for FP is expected to increase fertility rates and satisfaction among young patients with breast cancer. This study will provide the evidence to implement a multidisciplinary system for patients with breast cancer. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT05139641. Registered on December 1, 2021.