In Situ DESI-MSI Lipidomic Profiles of Breast Cancer Molecular Subtypes and Precursor Lesions.

Clinically meaningful molecular subtypes for classification of breast cancers have been established, however, initiation and progression of these subtypes remain poorly understood. The recent development of desorption electrospray ionization-mass spectrometry imaging (DESI-MSI) facilitates the convergence of analytical chemistry and traditional pathology, allowing chemical profiling with minimal tissue pretreatment in frozen samples. Here, we characterized the chemical composition of molecular subtypes of breast cancer with DESI-MSI. Regions of interest were identified, including invasive breast cancer (IBC), ductal carcinoma in situ (DCIS), and adjacent benign tissue (ABT), and metabolomic profiles at 200 µm elaborated using Biomap software and the Lasso method. Top ions identified in IBC regions included polyunsaturated fatty acids, deprotonated glycerophospholipids, and sphingolipids. Highly saturated lipids, as well as antioxidant molecules [taurine (m/z 124.0068), uric acid (m/z 167.0210), ascorbic acid (m/z 175.0241), and glutathione (m/z 306.0765)], were able to distinguish IBC from ABT. Moreover, luminal B and triple-negative subtypes showed more complex lipid profiles compared with luminal A and HER2 subtypes. DCIS and IBC were distinguished on the basis of cell signaling and apoptosis-related ions [fatty acids (341.2100 and 382.3736 m/z) and glycerophospholipids (PE (P-16:0/22:6, m/z 746.5099, and PS (38:3), m/z 812.5440)]. In summary, DESI-MSI identified distinct lipid composition between DCIS and IBC and across molecular subtypes of breast cancer, with potential implications for breast cancer pathogenesis. SIGNIFICANCE: These findings present the first in situ metabolomic findings of the four molecular subtypes of breast cancer, DCIS, and normal tissue, and add to the understanding of their pathogenesis.

A Molecular Portrait of High-Grade Ductal Carcinoma In Situ.

Ductal carcinoma in situ (DCIS) is a noninvasive precursor lesion to invasive breast carcinoma. We still have no understanding on why only some DCIS lesions evolve to invasive cancer whereas others appear not to do so during the life span of the patient. Here, we performed full exome (tumor vs. matching normal), transcriptome, and methylome analysis of 30 pure high-grade DCIS (HG-DCIS) and 10 normal breast epithelial samples. Sixty-two percent of HG-DCIS cases displayed mutations affecting cancer driver genes or potential drivers. Mutations were observed affecting PIK3CA (21% of cases), TP53 (17%), GATA3 (7%), MLL3 (7%) and single cases of mutations affecting CDH1, MAP2K4, TBX3, NF1, ATM, and ARID1A. Significantly, 83% of lesions displayed numerous large chromosomal copy number alterations, suggesting they might precede selection of cancer driver mutations. Integrated pathway-based modeling analysis of RNA-seq data allowed us to identify two DCIS subgroups (DCIS-C1 and DCIS-C2) based on their tumor-intrinsic subtypes, proliferative, immune scores, and in the activity of specific signaling pathways. The more aggressive DCIS-C1 (highly proliferative, basal-like, or ERBB2(+)) displayed signatures characteristic of activated Treg cells (CD4(+)/CD25(+)/FOXP3(+)) and CTLA4(+)/CD86(+) complexes indicative of a tumor-associated immunosuppressive phenotype. Strikingly, all lesions showed evidence of TP53 pathway inactivation. Similarly, ncRNA and methylation profiles reproduce changes observed postinvasion. Among the most significant findings, we observed upregulation of lncRNA HOTAIR in DCIS-C1 lesions and hypermethylation of HOXA5 and SOX genes. We conclude that most HG-DCIS lesions, in spite of representing a preinvasive stage of tumor progression, displayed molecular profiles indistinguishable from invasive breast cancer.

Immunohistochemical profile of high-grade ductal carcinoma in situ of the breast.

OBJECTIVE: To determine the frequency of the immunohistochemical profiles of a series of high-grade ductal carcinoma in situ of the breast. METHODS: One hundred and twenty-one cases of high-grade ductal carcinoma in situ, pure or associated with invasive mammary carcinoma, were identified from 2003 to 2008 and examined with immunohistochemistry for estrogen receptor, human epidermal growth factor receptor 2, cytokeratin 5, and epidermal growth factor receptor. The tumors were placed into five subgroups: luminal A, luminal B, HER2, basal-like, and "not classified". RESULTS: The frequencies of the immunophenotypes of pure ductal carcinoma in situ were the following: luminal A (24/42 cases; 57.1%), luminal B (05/42 cases; 11.9%), HER2 (07/42 cases; 16.7%), basal-like phenotype (00/42 cases; 0%), and "not classified" (06/42 cases; 14.3%). The immunophenotypes of ductal carcinoma in situ associated with invasive carcinoma were the following: luminal A (46/79 cases; 58.2%), luminal B (10/79 cases; 12.7%), HER2 (06/79 cases; 7.6%), basal-like (06/79 cases; 7.6%), and "not classified" (11/79 cases; 13.9%). There was no significant difference in the immunophenotype frequencies between pure ductal carcinoma in situ and ductal carcinoma in situ associated with invasive carcinoma (p>0.05). High agreement was observed in immunophenotypes between both components (kappa=0.867). CONCLUSION: The most common immunophenotype of pure ductal carcinoma in situ was luminal A, followed by HER2. The basal-like phenotype was observed only in ductal carcinoma in situ associated with invasive carcinoma, which had a similar phenotype.

Immunohistochemical profile of high-grade ductal carcinoma in situ of the breast

OBJECTIVE: To determine the frequency of the immunohistochemical profiles of a series of high-grade ductal carcinoma in situ of the breast. METHODS: One hundred and twenty-one cases of high-grade ductal carcinoma in situ, pure or associated with invasive mammary carcinoma, were identified from 2003 to 2008 and examined with immunohistochemistry for estrogen receptor, human epidermal growth factor receptor 2, cytokeratin 5, and epidermal growth factor receptor. The tumors were placed into five subgroups: luminal A, luminal B, HER2, basal-like, and “not classified”. RESULTS: The frequencies of the immunophenotypes of pure ductal carcinoma in situ were the following: luminal A (24/42 cases; 57.1%), luminal B (05/42 cases; 11.9%), HER2 (07/42 cases; 16.7%), basal-like phenotype (00/42 cases; 0%), and “not classified” (06/42 cases; 14.3%). The immunophenotypes of ductal carcinoma in situ associated with invasive carcinoma were the following: luminal A (46/79 cases; 58.2%), luminal B (10/79 cases; 12.7%), HER2 (06/79 cases; 7.6%), basal-like (06/79 cases; 7.6%), and “not classified” (11/79 cases; 13.9%). There was no significant difference in the immunophenotype frequencies between pure ductal carcinoma in situ and ductal carcinoma in situ associated with invasive carcinoma (p>0.05). High agreement was observed in immunophenotypes between both components (kappa=0.867). CONCLUSION: The most common immunophenotype of pure ductal carcinoma in situ was luminal A, followed by HER2. The basal-like phenotype was observed only in ductal carcinoma in situ associated with invasive carcinoma, which had a similar phenotype. .

[Node status in 454 ductal breast cancers cases according to the association with in situ component]. / Afectación ganglionar en 454 casos con carcinoma ductal infiltrante de mama según el hallazgo de componente intraductal asociado.

BACKGROUND: Studies have shown that breast infiltrating ductal carcinoma develops from precursor lesions or pre-invasive. It is accepted that the risk of invasive ductal carcinoma increased slightly in hyperplasia, but especially in cases of atypical hyperplasia and intraductal carcinoma. OBJECTIVES: To evaluate and compare the nodal status between ductal breast cancer with in situ component (group 1) or without it (group 2). MATERIAL AND METHOD: Descriptive and retrospective study that included 454 ductal breast cancers. Data concerning clinical and pathological variables was collected. All data was compared between both groups. RESULTS: Among all cases, 176 (38.8%) showed positive lymph nodes, 136 patients (39.5%) from group 1 and 40 cases (36.4%) from group 2. Among group 1 cases, high-grade subgroup showed higher positive lymph node rate (82 cases, 55.4%) than the extensive in situ carcinomas subgroup (84 cases, 49.7%). Both of them had a significant higher rate than group 2 cases (p = 0.003 y p = 0.028, respectively). Moreover, the low-grade in situ carcinomas without cellular necrosi had positive lymph nodes just in 30 cases (24%), significantly lower (p = 0.034) than group 2. CONCLUSIONS: We did not find overall statistical differences between groups depending on in situ associated component. But when we analyzed in situ subgroups, we found differences with higher positive lymph node rate in high grade carcinomas and extensive in situ carcinomas subgroups, while lower affectation rates were observed in low grade carcinomas (without cellular necrosis), compared to the group of breast cancers without in situ component associated.

Reproducibility of three classification systems of ductal carcinoma in situ of the breast using a web-based survey.

This study assessed the degree of diagnostic agreement among pathologists between three classification systems of ductal carcinoma in situ of the breast (DCIS). Thirteen pathologists received the same set of digitized images of microscopy of 43 DCIS cases and answered a questionnaire containing the criteria to compose the three classification systems studied: Holland, modified Lagios, and Van Nuys. A computer program was created, which organizes the information collected from each pathologist, supplying the histological grading of the cases within the three classification systems. The results were analyzed using percental agreement and the Kappa test. Diagnostic agreement for the three DCIS of the breast classification systems presented K values that varied from 0.27 to 0.37. Among the three classifications used, most agreement was for Van Nuys, showing a Kappa index of 0.37. These results matched the interobserver agreements, with Kappa indices varying from 0.13 to 0.64 for the Holland classification; 0.23 to 0.61 for the modified Lagios classification; and 0.23 to 0.74 for the Van Nuys classification. Pathologists specialized in breast pathology showed greater reproducibility for all the criteria evaluated. Comparing the three classification systems, diagnostic agreement and accuracy were rated higher for the classification of Van Nuys compared to modified Lagios and Holland.

Carcinoma ductal in situ: classificação e recomendações ao patologista cirúrugico / In situ ductal carcinoma: classification and guidelines for the surgical pathologist

Com o advento da mamografia preventiva de rotina, o diagnóstico de lesões precoces e de carcinoma ductal in situ da mama tem aumentado progressivamente nos últimos 10 anos. A classificação do carcinoma ductal in situ obedece basicamente parâmetros morfológicos como atipia e presença de necrose. No entanto, várias classificações diferentes foram propostas ao longo dos anos, com abordagens nem sempre equivalentes. Neste trabalho, abordamos criticamente as diferentes classificações disponíveis em ordem cronológica de aparecimento e sua aplicabilidade na rotina diagnóstica e terapêutica destas lesões.

In the past ten years, the introduction of screening mammography in breast cancer detection progressively increased the rate of diagnosis of premalignant lesions, such as in situ ductal carcinoma of the breast. Classification of in situ ductal carcinoma basically obeys morphological parameters, such as presence of atypia or necrosis. However, multiple different classifications have been proposed by distinct groups, with not always comparable approaches. In this review, we enlist the main working classifications available chronologically disposed along with diagnosis and therapeutic remarks, their applicability and reproducibility.