Application of deep learning on mammographies to discriminate between low and high-risk DCIS for patient participation in active surveillance trials.

BACKGROUND: Ductal Carcinoma In Situ (DCIS) can progress to invasive breast cancer, but most DCIS lesions never will. Therefore, four clinical trials (COMET, LORIS, LORETTA, AND LORD) test whether active surveillance for women with low-risk Ductal carcinoma In Situ is safe (E. S. Hwang et al., BMJ Open, 9: e026797, 2019, A. Francis et al., Eur J Cancer. 51: 2296-2303, 2015, Chizuko Kanbayashi et al. The international collaboration of active surveillance trials for low-risk DCIS (LORIS, LORD, COMET, LORETTA),  L. E. Elshof et al., Eur J Cancer, 51, 1497-510, 2015). Low-risk is defined as grade I or II DCIS. Because DCIS grade is a major eligibility criteria in these trials, it would be very helpful to assess DCIS grade on mammography, informed by grade assessed on DCIS histopathology in pre-surgery biopsies, since surgery will not be performed on a significant number of patients participating in these trials. OBJECTIVE: To assess the performance and clinical utility of a convolutional neural network (CNN) in discriminating high-risk (grade III) DCIS and/or Invasive Breast Cancer (IBC) from low-risk (grade I/II) DCIS based on mammographic features. We explored whether the CNN could be used as a decision support tool, from excluding high-risk patients for active surveillance. METHODS: In this single centre retrospective study, 464 patients diagnosed with DCIS based on pre-surgery biopsy between 2000 and 2014 were included. The collection of mammography images was partitioned on a patient-level into two subsets, one for training containing 80% of cases (371 cases, 681 images) and 20% (93 cases, 173 images) for testing. A deep learning model based on the U-Net CNN was trained and validated on 681 two-dimensional mammograms. Classification performance was assessed with the Area Under the Curve (AUC) receiver operating characteristic and predictive values on the test set for predicting high risk DCIS-and high-risk DCIS and/ or IBC from low-risk DCIS. RESULTS: When classifying DCIS as high-risk, the deep learning network achieved a Positive Predictive Value (PPV) of 0.40, Negative Predictive Value (NPV) of 0.91 and an AUC of 0.72 on the test dataset. For distinguishing high-risk and/or upstaged DCIS (occult invasive breast cancer) from low-risk DCIS a PPV of 0.80, a NPV of 0.84 and an AUC of 0.76 were achieved. CONCLUSION: For both scenarios (DCIS grade I/II vs. III, DCIS grade I/II vs. III and/or IBC) AUCs were high, 0.72 and 0.76, respectively, concluding that our convolutional neural network can discriminate low-grade from high-grade DCIS.

The type 2 inflammatory response favors recognition of tumor antigens by IgE in breast cancer.

BACKGROUND: Several studies describe an inverse statistical relationship between the presence of an allergy and development of cancer. However, the immunological mechanism involved in the relationship between these two degenerative diseases has not been explored. AIMS: The main objective of this study was to explore the possibility that the lymphocyte T helper (Th) 2 response, a characteristic of allergy, induces recognition of tumor antigens. METHODS AND RESULTS: Patients with a clinical diagnosis of breast ductal carcinoma were included. Histopathological markers related to proliferation of tumor cells were determined (Her-2-neu, Ki-67, estrogen receptor, and progesterone receptor). IHC was performed using IgE antibodies purified from an allergy patient and from each biopsy donor patient. Serum concentrations of cytokines representative of Th1 and Th2 inflammatory responses were determined. A total of 14 patients with a confirmed diagnosis of breast ductal carcinoma were included. IHC performed on biopsies showed a weak response when using purified IgE antibodies from an allergy patient; however, IHC using the IgE of each patient as the primary antibody showed an intense and highly specific signal. Serum concentrations of cytokines of the Th2 response, that is, IL-4 (130.5 pg/mL (116-135 pg/mL)), IL-5 (202 pg/mL (191-213 pg/mL)), and IL-13 (105.5 pg/mL (98-117 pg/mL)), were significantly higher than those of the Th1 response, that is, IL-6 (86 pg/mL (79-90 pg/mL)) and INF-γ (93 pg/mL (79-99 pg/mL)). CONCLUSION: Purified IgE antibodies specifically recognize tumor cells in breast ductal carcinoma.

Granulomatous lobular mastitis co-existing with ductal carcinoma in situ: Report of three cases and review of the literature.

Granulomatous lobular mastitis (GLM) is a benign and infrequent chronic breast ailment. Although this lesion can be clinically and radiographically mistaken for early-onset breast cancer, it is a rare occurrence for the two to coexist. This report describes three such cases. In all three patients, the primary signs and symptoms were related to the formation of diffuse breast masses or abscesses. Breast ultrasound and MRI revealed glandular edema and dilated breast ducts. The biopsies of all lesions exhibited both granulomatous inflammation confined to the lobules of the breast, abundant interstitial inflammatory cell infiltrates, and apparently cancerous cells located in dilated ducts with intact basement membranes. The surgically excised specimens confirmed the diagnosis of GLM and ductal carcinoma in situ (DCIS) in all three patients who underwent breast mass resection. By clinical imaging and clinical manifestations, GLM may obscure a concurrent DCIS, as highlighted by the cases reported herein.

Cytomorphological Assessment in Aspirates of Ductal Carcinoma in situ: Correlations with Histopathologic Grade, Architectural Pattern, and Invasion.

INTRODUCTION: Fine-needle aspiration biopsy (FNAB) of the breast is an effective and widely adopted diagnostic technique. Histopathologic grading of ductal carcinoma in situ (DCIS) has prognostic significance. In this current study, FNAB of DCIS was reviewed to identify parameters that predict grading, histopathologic architecture, and presence of invasion in DCIS. METHODS: Aspirates from histopathology-proven cases of DCIS were retrieved and reviewed for cytomorphologic parameters including cellularity, composition, epithelial fragment architecture cellular/nuclear features. RESULTS: In total 104 aspirates were reviewed. Cytopathologic cellular features - large nuclear size (p = 0.005), prominent nucleoli (p = 0.011), increased nuclear membrane irregularity (p = 0.043), high variation in nuclear size (p = 0.025), and presence of apoptotic figures in epithelial structures (p < 0.001); and background debris (p = 0.033) correlated with a high-grade diagnosis. Cytoplasmic vacuolation (p = 0.034) was seen exclusively in non-high-grade aspirates. Epithelial fragment architecture did not correlate with grading. A predominance (≥50%) of solid aggregates and papillary fragments on FNAB correlated with histopathologically solid (p = 0.039, p = 0.005) and papillary (p = 0.029, < p = 0.001) patterns. No parameter showed correlation with invasion. CONCLUSION: FNAB is effective in predicting DCIS grading. Epithelial fragment architecture assessment is limited to papillary or solid types, and FNAB cannot predict focal invasion in DCIS.

Expression-Based Diagnosis, Treatment Selection, and Drug Development for Breast Cancer.

There is currently no gene expression assay that can assess if premalignant lesions will develop into invasive breast cancer. This study sought to identify biomarkers for selecting patients with a high potential for developing invasive carcinoma in the breast with normal histology, benign lesions, or premalignant lesions. A set of 26-gene mRNA expression profiles were used to identify invasive ductal carcinomas from histologically normal tissue and benign lesions and to select those with a higher potential for future cancer development (ADHC) in the breast associated with atypical ductal hyperplasia (ADH). The expression-defined model achieved an overall accuracy of 94.05% (AUC = 0.96) in classifying invasive ductal carcinomas from histologically normal tissue and benign lesions (n = 185). This gene signature classified cancer development in ADH tissues with an overall accuracy of 100% (n = 8). The mRNA expression patterns of these 26 genes were validated using RT-PCR analyses of independent tissue samples (n = 77) and blood samples (n = 48). The protein expression of PBX2 and RAD52 assessed with immunohistochemistry were prognostic of breast cancer survival outcomes. This signature provided significant prognostic stratification in The Cancer Genome Atlas breast cancer patients (n = 1100), as well as basal-like and luminal A subtypes, and was associated with distinct immune infiltration and activities. The mRNA and protein expression of the 26 genes was associated with sensitivity or resistance to 18 NCCN-recommended drugs for treating breast cancer. Eleven genes had significant proliferative potential in CRISPR-Cas9/RNAi screening. Based on this gene expression signature, the VEGFR inhibitor ZM-306416 was discovered as a new drug for treating breast cancer.

Additional occult cancers identified on staging breast MRI: imaging appearances and pathologic characteristics.

INTRODUCTION: Breast magnetic resonance imaging (MRI) is increasingly being used for staging of patients with breast cancer due to its high sensitivity in detecting additional cancers (ACs). However, the clinical impact of diagnosing and treating these cancers remains unclear. METHODS: A retrospective study was undertaken of patients with newly diagnosed breast cancer who underwent staging MRI at The American University of Beirut Medical Centre (AUBMC) between 2012 and 2020. Pathology reports and breast MRI examinations were reviewed. Eighteen breast cancer patients with 19 pathology-proven index cancers (ICs) and 19 pathology-proven MRI-detected ACs were included. Chi-square and Fisher's exact tests for categorical variables and Wilcoxon signed rank test for numerical variables were used to compare ICs to ACs. RESULTS: The ICs consisted of four ductal carcinoma in situ (DCIS), 13 invasive ductal carcinomas (IDC), of which five with associated DCIS, and two invasive lobular carcinomas, (ILC) of which one with associated DCIS. ACs comprised 12 DCIS, five IDC, two with associated DCIS and two ILC, one with associated DCIS. Interval cancers were more frequently invasive whereas ACs were more frequently in situ (P = 0.021). ACs were more frequently nuclear grade 2 (P = 0.009). There was no statistically significant difference between ICs and ACs in lesion type (P = 0.062), shape (P = 0.073), initial enhancement (P = 1), delayed enhancement (P = 0.732), hormonal receptor profile (P = 0.68) and Ki67 (P = 0.388). Among ACs, ten (53%) were larger than 10 mm of which five (26%) were invasive cancers, and five (26%) were larger than the ICs. CONCLUSIONS: ACs detected by breast MRI were more likely to be in situ and to show a nuclear grade 2. Although not reaching statistical significance, some ACs tend to be clinically significant by their type, size or nuclear grade. The impact on clinical management remains to be determined.

The long-term psychosocial consequences of screen-detected ductal carcinoma in situ and invasive breast cancer.

OBJECTIVE: Ductal carcinoma in situ (DCIS) is a risk factor for invasive breast cancer (IBC). The prognosis of DCIS is considerably better than for IBC, yet women do not distinguish between the threat. We aimed to compare the psychosocial consequences of screen-detected DCIS and IBC, and to examine this comparison over time. METHODS: We surveyed a Danish mammography-screening cohort from 2004 to 2018. We assessed outcomes at six-time points: baseline, 1, 6, 18, 36 months, and 14 years after the screening. We measured psychosocial consequences with the Consequences Of Screening - Breast Cancer (COS-BC): a condition-specific questionnaire that is psychometrically validated and encompasses 14 psychosocial dimensions. We used weighted linear models with generalized estimating equations to compare responses between groups. We used a 1% level of significance. RESULTS: 170 out of 1309 women were diagnosed with breast cancer (13.0%). 23 were diagnosed with DCIS (13.5%) and 147 with IBC (86.5%). From baseline to six months after diagnosis, there were no significant differences between women with DCIS and IBC. However, mean scores indicated that IBC generally was more affected than DCIS. After six months, we observed that women with DCIS and IBC might be affected differently in the long term; mean scores and mean differences showed that IBC were more affected on some scales, while DCIS were on others. CONCLUSION: Overall, the DCIS and IBC experienced similar levels of psychosocial consequences. Women might benefit from renaming DCIS to exclude cancer nomenclature.

Axillary lymph node status and invasive lobular breast cancer : Analysis of the Clinical Tumor Register of the AGO Austria.

BACKGROUND: Invasive lobular carcinoma (ILC) represents the second most common type of invasive breast cancer (BC). Although ILC generally have good prognostic properties (positive estrogen receptor, ER, low tumor grade), they are generally diagnosed at a more advanced stage. The data on the axillary lymph node status in ILC compared to invasive ductal carcinoma (IDC) are considered controversial. Therefore, the aim of this study was to compare the pathological node stage (pN) between ILC and IDC in an Austria-wide register. METHODS: Data of the Clinical Tumor Register (Klinisches TumorRegister, KTR) of the Austrian Association for Gynecological Oncology (AGO) were retrospectively analyzed. Patients with primary early BC, invasive lobular or ductal, diagnosed between January 2014 and December 2018, and primary surgery were included. A total of 2127 tumors were evaluated and compared in 2 groups, ILC n = 303, IDC n = 1824. RESULTS: A total of 2095 patients were analyzed in the study. In the multivariate analysis, pN2 and pN3 were observed significantly more frequently in ILC compared with IDC (odds ratio, OR 1.93; 95% confidence interval, CI 1.19-3.14; p = 0.008 and OR 3.22; 95% CI: 1.47-7.03; p = 0.003; respectively). Other factors associated with ILC were tumor grades 2 and 3, positive ER, and pathological tumor stage (pT) 2 and pT3. In contrast, concomitant ductal carcinoma in situ, overexpression of the human epidermal growth factor receptor 2 (HER2), and a moderate and high proliferation rate (Ki67) were found less frequently in ILC. CONCLUSION: The data show an increased risk of extensive axillary lymph node metastasis (pN2/3) in ILC.

[Microglandular adenosis of the breast]. / Mikroglandulyarnyi adenoz molochnoi zhelezy.

The presented case describes the difficulties of diagnosis of the breast microglandular adenosis (MGA), taken by clinicians for a malignant process due to the nature of growth and large size. Criteria for histological and immunohistochemical diagnosis and differentiation of MGA with malignant neoplasms, in particular, with tubular breast carcinoma, are presented. Taking into account the rarity of the pathology and the absence of described cases in the Russian-language literature, the observation is of interest to pathologists and clinicians.

Differences in clinical characteristics and prognosis between breast neuroendocrine carcinoma and breast invasive ductal carcinoma: A multicentre population-based study from China.

AIM: We constructed a multicentre cohort in China to analyse the differences in clinical characteristics, treatment strategies and prognoses between breast neuroendocrine carcinoma (NEC) and invasive ductal carcinoma (IDC) of the breast. METHODS: All patients with early-stage breast cancer who attended three hospitals in Beijing from 2000 to 2018 were included in the study. We used propensity score matching to make a 1:3 match between NEC and IDC. RESULTS: After propensity score matching, 153 patients with IDC and 51 patients with NEC were analysed. Multivariate Cox regression showed that compared to patients with IDC, patients with NEC had a worse disease-free survival (HR = 2.94, 95% CI: 1.69-5.12, p < 0.001). CONCLUSION: NEC patients have a worse disease-free survival than IDC patients.

A Case Report of HER2-Amplification in the Breast Without Histological Abnormality.

Atypical ductal hyperplasia and low-grade ductal carcinoma in situ (DCIS) are regarded as precursor lesions of estrogen receptor (ER)-positive invasive breast cancer. In HER2-amplified invasive breast cancer, a precursor lesion before DCIS has not yet been described. Here we introduce a case of HER2-positive lobules in the breast without histological abnormality. A 39-year-old premenopausal woman visited a hospital due to identification of microcalcifications on screening mammography. The subsequent biopsy confirmed high-grade DCIS. She underwent wide excision, and a residual high-grade DCIS with a size of 1.4 cm was found. The tumor cells were hormone receptor positive and HER2 negative on immunohistochemical (IHC) staining. Around DCIS, there were terminal duct lobular units (TDLUs) showing strong HER2 positivity on IHC. These HER2-positive lobules were 7 mm away from the high-grade DCIS and was 1.1 mm in size. These HER2-positive lobules showed no histologic abnormality and had no difference compared with the surrounding normal TDLUs. Nevertheless, in addition to showing HER2 overexpression in IHC, HER2 amplification was also identified in HER2 silver in situ hybridization. HER2 amplification plays an important role in breast cancer development, and HER2 amplification is known to occur as an early event in cancer development. There have been studies identifying driver mutations in normal tissues of other organs. These findings suggest that HER2 amplification in the breast without histological abnormality could occur, and the HER2-positive lobules could be "at risk" for transformation into the precursor lesion of HER2-positive breast cancer, although the biological significance of these findings is unclear.

Is Sentinel Lymph Node Biopsy Necessary in Patients who Undergo Prophylactic Mastectomy?

BACKGROUND: Over the last decade, rates of risk-reducing prophylactic mastectomy (PM) have risen dramatically. A topic of debate regarding the procedure is whether to use sentinel lymph node biopsy (SLNB) at the time of PM and what factors might predict for such need. In order to assess the rate of identifying presence of occult invasive breast cancer in the PM specimen, we performed a retrospective review of the pathology findings from a single-surgeon case-series of PM. METHODS: Patients undergoing PM between January 2013 and June 2019 at Orlando Health Cancer Institute were identified for a retrospective chart review. Demographic, clinical, and histopathological data from the surgical procedure were collected and analyzed for the incidence of occult invasive breast cancer in the PM specimen. RESULTS: A total of 146 consecutive patients with PM were identified; 120 (82.2%) underwent contralateral PM (CPM) and 26 (17.8%) underwent bilateral PM (BPM). Final pathology of the 172 PM specimens identified 4 (3.3%) with lobular carcinoma in situ, 3 (2.5%) with atypical ductal hyperplasia, and 2 (1.7%) with atypical lobular hyperplasia and 2 (1.7%) with intraductal papilloma. No invasive malignancy was detected in any of the 172 PM specimens. CONCLUSIONS: The absence of occult invasive carcinoma in 172 consecutive PM specimens suggests a limited clinical utility in routinely performing SLNB in this setting. This study also suggests that use of preoperative breast MRI imaging could offer a potential non-invasive tool to detect occult malignancy and select patients who can safely undergo omission of SLNB at the time of PM.

Sino-orbital metastasis as the initial presentation of advanced breast cancer.

A woman in her 70s presented with reduced vision in her left eye, progressive narrowing of right eye opening for 6 months and anosmia. On examination, she had right enophthalmos and pseudoptosis with inferior globe dystopia. Her visual acuity was 6/9 and nil light perception in the right and left eyes, respectively. Extraocular muscle examination showed limited right up gaze. Funduscopy showed a normal right optic disc and left optic disc atrophy. Systemic examination revealed left breast ulceration with skin tethering. CT revealed an infiltrative mass invading the ethmoidal sinuses, frontal sinuses and both orbits. A histological diagnosis of infiltrative ductal breast carcinoma was made after nasal endoscopic and left breast biopsy. She underwent palliative chemoradiotherapy and survived with good disease control after 1 year. Metastatic carcinoma is a differential diagnosis of a sino-orbital mass, and comprehensive clinical assessment is indicated for all patients presenting with non-acute eye injury.

An insight into the invasion of breast ductal carcinoma in situ based on clinical, pathological and hematological data.

Background: Ductal carcinoma in situ (DCIS) has become a non-negligible part of breast cancers owing to the greatly increased incidence. While its natural history was not fully elucidated, which is the reason for current controversies in clinical treatment. Exploration of this issue from a clinical perspective is meaningful. Methods: Medical records of 389 patients diagnosed with DCIS or DCIS with invasive ductal carcinoma (IDC) were reviewed. All of them received appropriate medical care in our center. All 324 patients in training cohort were divided into invasion and non-invasion groups based on pathology. Differences in DCIS immunohistochemical markers and hematological indicators between them were analyzed. In the invasion group, differences between DCIS and matched IDC were compared to explore changes in the tumor heterogeneity during invasion. Conclusions are validated in the validation cohort of 65 patients. Results: Patients in invasion and non-invasion groups were balanced in baseline characteristics and no statistically significant differences were noticed for DCIS immunohistochemical markers. For hematological indicators, high expression of platelet >291.50) (odds ratio, 2.46; CI [1.35-4.46]; p = 0.003) and SII (>347.20) (odds ratio, 2.54; CI [1.56-4.12]; p < 0.001) were established as independent predictors for invasion by logistic analysis and were validated in the validation cohort. Ki-67 of IDC was significantly higher than that of matched DCIS (p < 0.001). HER2 expression and histological grade of DCIS were separately linearly related to those of IDC. Conclusion: The change in hematological indicators is an independent predictor for invasion and can be incorporated into the treatment decision-making process for DCIS. Invasion tumor cells exhibit a stronger proliferative capacity compared with the in-situ ones. There are linear relationships in HER2 expression and histological grades between DCIS and matched IDC. DCIS subclones with different histological grades will develop into invasive carcinomas separately.

Secretory Carcinoma of the Breast Mimicking Invasive Ductal Carcinoma: A Case Report.

BACKGROUND Secretory breast carcinoma (SBC), an extremely rare malignancy, is related to a chromosomal translocation which leads to an ETV6-NTRK3 fusion mutation. SBC is characterized by eosinophilic secretions and is usually triple-negative, with a small number of patients demonstrating ER-positivity of the tumors. Diagnosis can be challenging and requires genomic testing for confirmation. CASE REPORT A 40-year-old woman presented with a breast mass found on mammography. She underwent an ultrasound-guided biopsy of the tumor. Initial pathology evaluation revealed features consistent with invasive ductal carcinoma. The immunochemistry report described an ER-positive, PR-negative, and HER2-negative tumor. The specimen was sent for oncotype scoring, which was not performed due to the specimen not meeting the criteria for invasive ductal carcinoma and displaying pathological features of SBC. A fluorescent in situ hybridization (FISH) study revealed ETV6 translocation, consistent with the diagnosis of SBC. The patient underwent lumpectomy followed by adjuvant radiotherapy and endocrine therapy. She remains in complete remission 3 years after treatment. CONCLUSIONS Accurately diagnosing SBC is of extreme importance as it has an indolent clinical course, but has a favorable prognosis if detected early. Due to nonspecific imaging findings, pathology evaluation with immunohistochemical staining followed by genomic testing is required. Our case highlights the challenges associated with SBC diagnosis requiring genomic testing due to equivocal pathological findings, along with increasing incidence of SBT in adults. There are no established guidelines for SBC management. The mainstay of treatment is partial or total mastectomy. Data on the benefits of adjuvant endocrine therapy, chemotherapy, and radiotherapy are inconclusive.

The Clinicopathological Characteristics of Pure and Mixed Invasive Micropapillary Breast Carcinomas: A Single Center Experience.

Background: Invasive micropapillary carcinoma (IMPC) is a rare tumor of the breast. IMPC can be classified as a pure or mixed type based on the extent of micropapillary differentiation. Aims: To evaluate the prognostic importance of the IMPC component in breast cancer through retrospective comparison of the clinicopathological characteristics and clinical outcomes of pure and mixed IMPC patients. Study Design: The data of 147 (2.2%) patients with IMPC among 6648 patients histopathologically diagnosed with invasive breast cancer between January 2000-2022 were retrospectively reviewed. The patients were assigned to two groups: pure IMPC and mixed IMPC. Methods: The clinicopathological features such as age at diagnosis, histological type, grade, size, and components of mixed carcinoma, the numbers of metastatic lymph nodes, presence of lymph vascular invasion, hormone receptor, and the Her-2 status of the tumor, T, N, M stages, and the survival rates were reviewed. The clinicopathologic features, patterns of failures, and survival rates were coded and compared between pure and mixed IMPC patients. Results: A total of 45 patients (30.6%) had pure and 102 patients (69.4%) had mixed IMPC. The median follow-up time was 46 months (3-178). The progesterone receptor positivity rate was significantly lower in the pure group than in the mixed group (66.7% vs. 83.3%, p: 0.024). In the pure and mixed groups, respectively, the 5-year overall survival was 90% and 91% (p: 0.839); progression-free survival was 70% and 77% (p: 0.537); locoregional recurrence-free survival was 86% and 95% (p: 0.043); 5-year distant metastasis-free survival was 88% and 83% (p: 0.066), and the locoregional recurrence rate was 10.3% and 2% (p: 0.052). Conclusion: Compared to the mixed IMPC, pure IMPC appears to have a more aggressive behavior with lower locoregional recurrence-free survival and more locoregional recurrences. This may be due to the low progesterone receptor positivity rate.

Primary Ectopic Breast Carcinoma in Man Mimicking Keloid.

Background: Ectopic breast tissues (EBT) are developmental abnormality found in 1-6% of normal population. Like an orthotopic breast tissue, ectopic breast may have similar pathological changes including malignancy. Breast cancer as well as ectopic breast tissue in male are extremely rare. We present a case of ectopic breast carcinoma (EBC) in middle aged man mimicking keloid. Case report: A forty-two-year-old Indo-Aryan male referred from primary health care to the dermatology clinic with firm multi-nodular, non-tender, fleshy sessile mass on his right axilla measuring two by three cm in diameter. Excision of this lesion revealed moderately differentiated ductal carcinoma consistent with ectopic breast carcinoma. Conclusion: We report this case to shed light on such a rare condition and to keep in mind that ectopic breast carcinoma should be in differential diagnosis of any suspicious mass in axillae.

Patients with Invasive Lobular Carcinoma Show a Significant Increase in IRS-4 Expression Compared to Infiltrative Ductal Carcinoma-A Histopathological Study.

Background and Objectives: Breast cancer (BC) is the first diagnosed type of cancer and the second leading cause of cancer-related mortality in women. In addition, despite the improvement in treatment and survival in these patients, the global prevalence and incidence of this cancer are rising, and its mortality may be different according to the histological subtype. Invasive lobular carcinoma (ILC) is less common but entails a poorer prognosis than infiltrative ductal carcinoma (IDC), exhibiting a different clinical and histopathological profile. Deepening study on the molecular profile of both types of cancer may be of great aid to understand the carcinogenesis and progression of BC. In this sense, the aim of the present study was to explore the histological expression of Insulin receptor substrate 4 (IRS-4), cyclooxygenase 2 (COX-2), Cyclin D1 and retinoblastoma protein 1 (Rb1) in patients with ILC and IDC. Patients and Methods: Thus, breast tissue samples from 45 patients with ILC and from 45 subjects with IDC were analyzed in our study. Results: Interestingly, we observed that IRS-4, COX-2, Rb1 and Cyclin D1 were overexpressed in patients with ILC in comparison to IDC. Conclusions: These results may indicate a differential molecular profile between both types of tumors, which may explain the clinical differences among ILC and IDC. Further studies are warranted in order to shed light onto the molecular and translational implications of these components, also aiding to develop a possible targeted therapy to improve the clinical management of these patients.

Pathological underestimation and biomarkers concordance rates in breast cancer patients diagnosed with ductal carcinoma in situ at preoperative biopsy.

Ductal carcinoma in situ (DCIS) often upgrade to invasive breast cancer at surgery. The current study aimed to identify factors associated with pathological underestimation and evaluate concordance rates of biomarkers between biopsy and surgery. Patients diagnosed with DCIS at needle biopsy from 2009 to 2020 were retrospectively reviewed. Univariate and multivariate analyses were performed to identify factors associated with pathological underestimation. Concordance rates between paired biopsy samples and surgical specimens were evaluated. A total of 735 patients with pure DCIS at biopsy were included, and 392 patients (53.3%) underwent pathological underestimation at surgery. Multivariate analysis demonstrated that tumor size > 5.0 cm [odds ratio (OR) 1.79], MRI BI-RADS ≥ 5 categories (OR 2.03), and high nuclear grade (OR 2.01) were significantly associated with pathological underestimation. Concordance rates of ER, PR, HER2 status and Ki-67 between biopsy and surgery were 89.6%, 91.9%, 94.8%, and 76.4% in lesions without pathological underestimation, and were 86.4%, 93.2%, 98.2% and 76.3% for in situ components in lesions with pathological underestimation. Meanwhile, in situ components and invasive components at surgery had concordance rates of 92.9%, 93.8%, 97.4%, and 86.5% for those biomarkers, respectively. In conclusion, lesions diagnosed as DCIS at biopsy have a high rate of pathological underestimation, which was associated with larger tumor size, higher MRI BI-RADS category, and higher nuclear grade. High concordances were found in terms of ER, PR, and HER2 status evaluation between biopsy and surgery, regardless of the pathological underestimation.