Clinicopathologic features and prognoses of different histologic types of triple-negative breast cancer: A large population-based analysis

Immunohistochemical Characterization of a Large Cohort of Triple Negative Breast Cancer

Introduction. Triple negative breast carcinomas are characterized by a lack of hormone receptor and HER2 expression and inconsistent expression of breast-specific immunohistochemical markers. The expression of many site-specific markers in these tumors is largely unknown. The objective of the study was to examine the expression of widely used immunohistochemical markers on a large cohort of triple negative breast cancer. Methods. Sections from tissue microarrays were stained with 47 markers using routine protocols. Most markers were scored using a modified Allred method. ATRX, BAP1, SMAD4, e-cadherin, and beta-catenin were scored as retained or lost. Mammaglobin was considered positive if there was at least moderate intensity staining in any tumor cells. P16 was scored as overexpressed or not overexpressed; p53 was scored as wildtype, overexpressed, null, or cytoplasmic. Results. The cohort consisted of 639 tumors including 601 primary and 32 metastases. Overall, 96% expressed GATA3, mammaglobin, and/or SOX10 while 97% of no special type tumors expressed this panel. Carcinoma of apocrine differentiation demonstrated an AR positive, SOX10 negative, K5 negative/focal immunophenotype. PAX8 (SP348), WT1, Napsin A, and TTF1 (8G7G3/1) were never or rarely expressed while CA9, CDX2, NKX3.1, SATB2 (SATBA410), synaptophysin, and vimentin were variably expressed. Conclusions. Almost all TNBC express at least 1 of the 3 IHC markers: GATA3, mammaglobin, and/or SOX10. Carcinoma of apocrine differentiation is characterized by an AR positive, SOX10 negative, K5 negative or focal immunophenotype. Cautious interpretation of so-called site-specific markers, with knowledge of antibody clones, is required in excluding the diagnosis of triple negative breast cancer.

Association of microRNA-21 expression with breast cancer subtypes and its potential as an early biomarker

Breast cancer has become the most diagnosed cancer worldwide in 2020 with high morbidity and mortality rates. The alarming increase in breast cancer incidence has sprung many researchers to focus on developing novel screening tests to identify early breast cancer which will allow clinicians to provide timely and effective treatments. With much evidence supporting the notion that the deregulation of miRNAs (a class of non-coding RNA) greatly contributes to cancer initiation and progression, the promising role of miRNAs as cancer biomarkers is gaining traction in the research world. Among the upregulated miRNAs identified in breast carcinogenesis, miR-21 was shown to be significantly expressed in breast cancer tissues and bodily fluids of breast cancer patients. Therein, this review paper aims to provide an overview of breast cancer, the role and significance of miR-21 in breast cancer pathogenesis, and its potential as a breast cancer biomarker. The paper also discusses the current types of tumor biomarkers and their limitations, the presence of miR-21 in extracellular vesicles and plasma, screening methods available for miRNA detection along with some challenges faced in developing diagnostic miR-21 testing for breast cancer to provide readers with a comprehensive outlook based on using miR-21 in clinical settings.

Triple-negative breast cancer: from none to multiple therapeutic targets in two decades

Triple-negative breast cancers (TNBCs) are more likely to occur in younger patients and have a poor prognosis. They are highly heterogeneous tumors consisting of different molecular subtypes. The only common characteristic among them is the absence of targets for endocrine therapy and human epidermal growth factor receptor 2 (HER2) blockade. In the past two decades, there has been an increased understanding of these tumors from a molecular perspective, leading to their stratification according to new therapeutic strategies. TNBC has ushered breast carcinomas into the era of immunotherapy. The higher frequency of germline BRCA mutations in these tumors enables targeting this repair defect by drugs like PARP inhibitors, resulting in synthetic lethality in neoplastic cells. Additionally, we have the identification of new molecules to which this generation of smart drugs, such as antibody-drug conjugates (ADCs), are directed. In this review, we will discuss the trajectory of this knowledge in a systematic manner, presenting the molecular bases, therapeutic possibilities, and biomarkers.

Triple-negative Breast Carcinoma With Apocrine and Histiocytoid Features: A Clinicopathologic and Molecular Study of 18 Cases

Triple-negative breast cancer (TNBC) is a heterogenous group of tumors. Most TNBCs are high-grade aggressive tumors, but a minority of TNBCs are not high grade, with relatively indolent behavior and specific morphologic and molecular features. We performed a clinicopathologic and molecular assessment of 18 non-high-grade TNBCs with apocrine and/or histiocytoid features. All were grade I or II with low Ki-67 (≤20%). Thirteen (72%) showed apocrine features, and 5 (28%) showed histiocytoid and lobular features. In all, 17/18 expressed the androgen receptor, and 13/13 expressed gross cystic disease fluid protein 15. Four (22.2%) patients were treated with neoadjuvant chemotherapy, but none achieved a pathologic complete response. In all, 2/18 patients (11%) had lymph node metastasis at the time of surgery. None of the cases had a recurrence or disease-specific death, with an average follow-up time of 38 months. Thirteen cases were profiled by targeted capture-based next-generation DNA sequencing. Genomic alterations (GAs) were most significant for PI3K-PKB/Akt pathway (69%) genes, including PIK3R1 (23%), PIK3CA (38%), and PTEN (23%), and RTK-RAS pathway (62%) including FGFR4 (46%) and ERBB2 (15%). TP53 GA was seen in only 31% of patients. Our findings support those on high-grade TNBCs with apocrine and/or histiocytoid features as a clinicopathologic and genetically distinct subgroup of TNBC. They can be defined by features including tubule formation, rare mitosis, low Ki-67 (≤20%), triple-negative status, expression of androgen receptor and/or gross cystic disease fluid protein 15, and GA in the PI3K-PKB/Akt and/or RTK-RAS pathway. These tumors are not sensitive to chemotherapy but have favorable clinical behavior. Tumor subtype definitions are the first step to implementing future trial designs to select these patients.

Next-Generation Sequencing and Triple-Negative Breast Cancer: Insights and Applications

The poor survival of triple-negative breast cancer (TNBC) is due to its aggressive behavior, large heterogeneity, and high risk of recurrence. A comprehensive molecular investigation of this type of breast cancer using high-throughput next-generation sequencing (NGS) methods may help to elucidate its potential progression and discover biomarkers related to patient survival. In this review, the NGS applications in TNBC research are described. Many NGS studies point to TP53 mutations, immunocheckpoint response genes, and aberrations in the PIK3CA and DNA repair pathways as recurrent pathogenic alterations in TNBC. Beyond their diagnostic and predictive/prognostic value, these findings suggest potential personalized treatments in PD -L1-positive TNBC or in TNBC with a homologous recombination deficit. Moreover, the comprehensive sequencing of large genomes with NGS has enabled the identification of novel markers with clinical value in TNBC, such as AURKA, MYC, and JARID2 mutations. In addition, NGS investigations to explore ethnicity-specific alterations have pointed to EZH2 overexpression, BRCA1 alterations, and a BRCA2-delaAAGA mutation as possible molecular signatures of African and African American TNBC. Finally, the development of long-read sequencing methods and their combination with optimized short-read techniques promise to improve the efficiency of NGS approaches for future massive clinical use.

Metaplastic breast cancer: A review

Metaplastic breast cancer (MpBC) is an uncommon aggressive malignancy that is associated with a poor prognosis. Due to its rarity, the relationships between the clinical and pathological features of MpBC, treatment approach, and clinical outcomes remain underexplored. In the following review article, we synthesize the existing data on the clinical, pathological and genomic features, management, and outcomes of MpBC. We also identify potential targets for future clinical trials.

Geriatric Early-Stage Triple-Negative Breast Cancer Patients in Low-risk Population: Omitting Chemotherapy Based on Nomogram

BACKGROUND

Considering old age and comorbidities, the actual benefit of chemotherapy in older patients with early triple-negative breast cancer (TNBC) remains uncertain. We aimed to select appropriate patients who could avoid chemotherapy in this population.

METHODS

A total of 6482 patients more than 65 years old with T1-2N0-1M0 TNBC in 2010-2015 were extracted from SEER program. Multivariate logistic regression was performed to identify independent factors associated with chemotherapy usage. Survival analysis was performed using Kaplan-Meier plots and log-rank tests. Independent prognostic factors were identified by multivariate Cox analysis. A nomogram predicting breast cancer-specific survival (BCSS) and a risk stratification model were constructed.

RESULTS

A total of 3379 (52.13%) patients received chemotherapy while 3103 (47.87%) did not. Age, married status, grade, T-stage, N-stage, radiation and breast-conserving surgery (BCS) were significantly associated with chemotherapy usage (all P < .05). Chemotherapy significantly improved OS (HR = 0.606, P < .001) and BCSS (HR = 0.763, P = .006) in the entire population. A nomogram was built by incorporating independent risk factors (age, T-stage, N-stage, grade and radiation). Based on the score of the nomogram, the risk stratification model demonstrated that chemotherapy improved OS (P < .001) and BCSS (P < .001) of patients in the high-risk group (score >180), but not in the low-risk group (score ≤75).

CONCLUSION

Chemotherapy is beneficial for geriatric patients with T1-2N0-1M0 TNBC in this study, and the risk stratification model indicates the feasibility of sparing chemotherapy in low-risk subgroup without sacrificing survival, providing clinicians tools to weigh the risk-benefit of chemotherapy and customize the individualized treatment accordingly.

Immunologically "cold" triple negative breast cancers engraft at a higher rate in patient derived xenografts

TNBC is a heterogeneous subtype of breast cancer, and only a subset of TNBC can be established as PDXs. Here, we show that there is an engraftment bias toward TNBC with low levels of immune cell infiltration. Additionally, TNBC that failed to engraft show gene expression consistent with a cancer-promoting immunological state, leading us to hypothesize that the immunological state of the tumor and possibly the state of the immune system of the host may be essential for engraftment.

Metaplastic breast cancers and triple-negative breast cancers of no special type: are they prognostically different? A systematic review and meta-analysis

BACKGROUND AND AIMS

Metaplastic breast cancer (MBC) and triple-negative (TN) BC of no special type are often confounded with each other in terms of survival and prognosis. In this systematic study and meta-analysis, we evaluated the prognosis of each of these two different diagnoses.

METHODS

We conducted a systematic literature search and review using the MOOSE guidelines, through PUBMED database, the Ovid MEDLINE database, and the ISI Web of Science Citation Index Expanded (SCI Expanded). Overall survival (OS) and disease-free survival (DFS) were the main outcomes considered.

RESULTS

Our review eventually selected six independent studies, with a total of more than 59 519 patients. MBC was found to associate with worse OS compared to TNBC of no special type, with a significant 40% increased risk of death [summary hazard ratio (SHR) = 1.40, 95% confidence interval (CI): 1.30-1.50]. We found neither heterogeneity ( I2 = 0%) nor evidence of publication bias ( P = 0.82 and P = 0.49 by Begg's and Egger's test, respectively) between studies. No statistically significant difference was found between MBC and TNBC of no special type in terms of DFS (SHR = 1.17, 95% CI: 0.80-1.71).

CONCLUSION

This study demonstrates that TNBC of no special type and MBC have comparable DFS, although the latter presents a significantly worse prognosis in terms of OS. Despite DFS being similar in both subtypes, this did not result in significant OS benefits, with MBC score being the worse of the two diseases.

Diagnostic and Prognostic Nomograms for Lung Metastasis in Triple-Negative Breast Cancer

Background

The lungs are one of the common sites of metastasis of triple-negative breast cancer (TNBC). Patients with lung metastases (LM) have a shorter duration of survival. This study is aimed at determining the prognostic factors of patients with TNBC with LM and constructing two nomograms to assess the risk of LM and the prognosis of patients with TNBC with LM.

Methods

Clinicopathological and follow-up data of patients with TNBC between 2010 and 2015 were retrieved from the Surveillance, Epidemiology, and End Results (SEER) database. Univariate and multivariate Cox regression analyses were used to screen for independent predictors of LM in patients with TNBC and identify the independent prognostic factors of patients with TNBC with LM. The two nomograms were appraised using calibration curves, receiver operating characteristic (ROC) curves, and decision curve analysis (DCA).

Results

A total of 27,048 patients with TNBC were included in this study. Age, tumour size, T stage, and N stage were identified as independent risk factors for LM in patients with TNBC. Histological type, marital status, prior surgery, chemotherapy, bone metastases, brain metastases, and LM were confirmed as independent prognostic factors for patients with TNBC with LM. The area under the ROC curve (AUC) of the diagnostic nomogram was 0.838 (95% confidence interval 0.817-0.860) in the training cohort and 0.894 (95% confidence interval 0.875-0.917) in the verification cohort. The AUC values of the 6-, 12-, and 18-month prognostic nomograms in the training cohort were 0.809 (95% confidence interval 0.771-0.868), 0.779 (95% confidence interval 0.737-0.834), and 0.735 (95% confidence interval 0.699-0.811), respectively, and the corresponding AUC values in the validation cohort were 0.735(95% confidence interval 0.642-0.820), 0.672 (95% confidence interval 0.575-0.758), and 0.705 (95% confidence interval 0.598-0.782), respectively. According to the calibration curves and data analysis, both nomograms exhibited good performance.

Conclusion

We successfully constructed and verified two valuable nomograms for predicting the incidence of LM and prognosis of patients TNBC with LM.

HER2-positive apocrine carcinoma of the breast: a population-based analysis of treatment and outcome

PURPOSE

Apocrine carcinoma of the breast (APO) expresses HER2 in 30-50% of cases. This study explored the clinicopathological features and outcome of HER2+/APO and matched HER2+/NST cohort.

METHODS

We used the SEER database to explore the cohorts. Univariate and multivariate analyses were used to assess the survival. Based on ER and PR [steroid receptors/SR/] and HER2 status, we divided the cohorts to match the intrinsic molecular subtypes for comparisons.

RESULTS

We retrieved 259 cases of HER2+/APO. Most HER2+/APO were SR negative (65%). HER2+/APO were more prevalent in the 80+ age group (24.7% vs. 15.7%, p < 0.001). HER2+/SR-/APO had a significantly lower histological grade than the HER2+/SR-/NST (p < 0.001). Breast cancer-related deaths were more prevalent in HER2+/NST (7.8% vs. 3.9%, p = 0.019). This was particularly evident between SR- subgroups (10.4% in HER2+/SR-/NST vs. 4.2% in HER2+/SR-/APO, p = 0.008) and was reaffirmed in breast cancer-specific survival in univariate analysis (p = 0.03). Other than race and SR status, HER2+/APO subgroups did not differ in clinicopathological parameters.

CONCLUSIONS

Our study confirms the rarity of the APO and reveals that SR status in APO does not affect these patients' prognosis. HER2+/APO tumors tend to have a less aggressive phenotype and a more favorable outcome despite a markedly lower ER/PR positivity.

Clinicopathologic and Genomic Features in Triple-Negative Breast Cancer Between Special and No-Special Morphologic Pattern

Background

Triple-negative breast cancer (TNBC) is refractory and heterogeneous, comprising various entities with divergent phenotype, biology, and clinical presentation. As an aggressive subtype, Chinese TNBC patients with special morphologic patterns (STs) were restricted to its incidence of 10-15% in total TNBC population.

Methods

We recruited 89 patients with TNBC at Guangdong Provincial People’s Hospital (GDPH) from October 2014 to May 2021, comprising 72 cases of invasive ductal carcinoma of no-special type (NSTs) and 17 cases of STs. The clinical data of these patients was collected and statistically analyzed. Formalin-fixed, paraffin-embedded (FFPE) tumor tissues and matched blood samples were collected for targeted next-generation sequencing (NGS) with cancer-related, 520- or 33-gene assay. Immunohistochemical analysis of FFPE tissue sections was performed using anti-programmed cell death-ligand 1(PD-L1) and anti-androgen receptor antibodies.

Results

Cases with NSTs presented with higher histologic grade and Ki-67 index rate than ST patients (NSTs to STs: grade I/II/III 1.4%, 16.7%,81.9% vs 0%, 29.4%, 58.8%; p<0.05; Ki-67 ≥30%: 83.3% vs. 58.8%, p<0.05), while androgen receptor (AR) and PD-L1 positive (combined positive score≥10) rates were lower than of STs cases (AR: 11.1% vs. 47.1%; PD-L1: 9.6% vs. 33.3%, p<0.05). The most commonly altered genes were TP53 (88.7%), PIK3CA (26.8%), MYC (18.3%) in NSTs, and TP53 (68.8%), PIK3CA (50%), JAK3 (18.8%), KMT2C (18.8%) in STs respectively. Compared with NSTs, PIK3CA and TP53 mutation frequency showed difference in STs (47.1% vs 19.4%, p=0.039; 64.7% vs 87.5%, p=0.035).

Conclusions

In TNBC patients with STs, decrease in histologic grade and ki-67 index, as well as increase in PD-L1 and AR expression were observed when compared to those with NSTs, suggesting that TNBC patients with STs may better benefit from immune checkpoint inhibitors and/or AR inhibitors. Additionally, lower TP53 and higher PIK3CA mutation rates were also found in STs patients, providing genetic evidence for deciphering at least partly potential mechanism of action.

Special Histologic Type and Rare Breast Tumors - Diagnostic Review and Clinico-Pathological Implications

Breast cancer is the most common malignant tumor in females. While most carcinomas are categorized as invasive carcinoma, no special type (NST), a diverse group of tumors with distinct pathologic and clinical features is also recognized, ranging in incidence from relatively more common to rare. So-called "special histologic type" tumors display more than 90% of a specific, distinctive histologic pattern, while a spectrum of tumors more often encountered in the salivary gland may also arise in the breast. Metaplastic carcinomas can present diagnostic challenges. Some uncommon tumors harbor pathognomonic genetic alterations. This article provides an overview of the key diagnostic points and differential diagnoses for this group of disparate lesions, as well as the salient clinical characteristics of each entity.

Clinical outcomes in patients with triple negative or HER2 positive lobular breast cancer: a single institution experience

PURPOSE

Invasive lobular carcinomas (ILC) are characterised by loss of the cell adhesion molecule E-cadherin. Approximately 15% of ILC are ER negative at the time of breast cancer diagnosis, or at relapse due to loss of ER expression. Less than 5% of classical ILC but up to 35% of pleomorphic ILC are HER2 positive (HER2+).

METHODS

Retrospective analysis of clinic-pathological data from patients with Triple negative (TN) or HER2+ ILC diagnosed 2004-2014 at the Royal Marsden Hospital. The primary endpoint was median overall survival (OS) in patients with metastatic disease. Secondary endpoints included response rate to neo-adjuvant chemotherapy (NAC), median disease-free interval (DFI) and OS for patients with early disease.

RESULTS

Three of 16 patients with early TN ILC and 7/33 with early HER2+ ILC received NAC with pCR rates of 0/3 and 3/5 patients who underwent surgery, respectively. Median DFI was 28.5 months [95% Confidence interval (95%CI) 15-78.8] for TN ILC and not reached (NR) (111.2-NR) for HER2+ early ILC. Five-year OS was 52% (95%CI 23-74%) and 77% (95%CI 58-88%), respectively. Twenty-three patients with advanced TN ILC and 14 patients with advanced HER2+ ILC were identified. Median OS was 18.3 months (95%CI 13.0-32.8 months) and 30.4 months (95%CI 8.8-NR), respectively.

CONCLUSIONS

In our institution we report a high relapse rate after treatment for early TN ILC, but median OS from metastatic disease is similar to that expected from TN IDC. Outcomes for patients with advanced HER2+ ILC were less favourable than those expected for IDC, possibly reflecting incomplete exposure to anti-HER2 therapies.

CLINICAL TRIAL REGISTRATION

ROLo (ClinicalTrials.gov Identifier: NCT03620643), ROSALINE (ClinicalTrials.gov Identifier: NCT04551495).

Chemotherapy significantly improves long-term survival of small lesion node negative metaplastic breast carcinoma in T1c population rather than T1a and T1b

Metaplastic breast carcinoma (MpBC) is considered a highly aggressive disease, the outcome of chemotherapy on small lesions (T1abcN0M0) MpBC patients remain unclear. We identified 890 female MpBC patients in the Surveillance, Epidemiology, and End Results (SEER) database from 2000 to 2016. After propensity score matching (PSM), 584 patients were matched. Survival probability was compared among T1a, T1b, and T1c patients and between patients with and without chemotherapy using Kaplan-Meier analysis and Cox proportional hazard analysis. Significance was set at two-sided P < 0.05. We classified 49, 166, and 675 patients as T1a, T1b, and T1c MpBC, respectively. The chemotherapy group included 404 patients (45.4%). Following PSM, survival analysis indicated that the patients who underwent chemotherapy had higher OS (P = 0.0002) and BCSS (P = 0.0276) in the T1c substage, but no significant difference was detected in T1a or T1b patients. In this population-based study, small lesion MpBC showed a favorable prognosis. Chemotherapy improved the prognosis of T1c MpBC patients but not T1a and T1b patients to a beneficial extent. Our findings may offer novel insight into a therapeutic strategy for MpBC.

An Update on the Molecular and Clinical Characteristics of Apocrine Carcinoma of the Breast

Apocrine carcinoma of the breast is a rare malignancy. According to 2019 WHO classification, apocrine cellular features and a characteristic steroid receptor profile (Estrogen receptor (ER)-negative and androgen receptor (AR)-positive) define apocrine carcinoma. Her-2/neu protein expression is reported in ∼30-50% of apocrine carcinomas, while NGS analysis showed frequent PIK3CA/PTEN/AKT and TP53 mutations Followed by deregulation in the mitogen-activated protein kinase pathway components (mutations of KRAS, NRAS, BRAF). A recent miRNA study indicates various miRNAs (downregulated hsa-miR-145-5p and upregulated 14 miRNAs such as hsa-miR-182-5p, hsa-miR-3135b, and hsa-miR-4417) may target the commonly altered pathways in apocrine carcinomas such as ERBB2/HER2 and mitogen-activated protein kinase signaling pathway. Although AR expression is a hallmark of apocrine carcinoma, little is known regarding the efficacy/resistance to antiandrogens. Success of bicalutamide, a non-steroidal anti-androgen, was reported in a case of Her2-negative apocrine carcinoma. Two recent studies, however, described presence of anti-androgen resistance biomarkers (a splice variant ARv7 and AR/NCOA2 co-amplification) in a subset of AR+ apocrine carcinomas, cautioning the use of anti-androgens in AR+ triple-negative breast carcinomas. Apocrine carcinomas rarely show biomarkers predictive of response to immune checkpoint inhibitors (PD-L1 expression, MSI-H status, and TMB-high). Therefore, a comprehensive cancer profiling of apocrine carcinomas is necessary to identify potential therapeutic targets for a truly individualized treatment approach.

Apocrine lesions of the breast

Apocrine change is recognised in benign, atypical and malignant lesions of the breast. Apocrine metaplasia, a frequent finding in the breast of women over the age of 25 years, is most commonly seen in benign cysts with a simple or papillary configuration. Apocrine change is also recognised in other benign lesions including sclerosing adenosis, now known as apocrine adenosis. Apocrine atypia usually refers to cytological atypia in which there is at least threefold variation in nuclear size but architectural atypia may also occur. The distinction between atypical apocrine hyperplasia and non-high-grade apocrine ductal carcinoma in situ may be difficult due to the relative rarity of these entities and the lack of validated diagnostic criteria. Lobular carcinoma in situ (LCIS) with apocrine change is considered to be a variant of pleomorphic LCIS. An apocrine variant of encapsulated papillary carcinoma is also recognised. Apocrine change is described in invasive carcinoma, including no special type, lobular, micropapillary and mucinous variants. The recent WHO 2019 update recognises 'carcinoma with apocrine differentiation' as a special type breast carcinoma based on the presence of apocrine morphology in at least 90% of the tumour. Tumours with apocrine morphology are usually but not always hormone receptor negative. Human epidermal growth factor receptor 2 (HER-2) status is variable. Molecular studies have identified breast tumours with apocrine features and high expression of androgen receptor mRNA including 'luminal androgen receptor tumours' and 'molecular apocrine tumours'. The term 'pure apocrine carcinoma' has been proposed to describe an invasive carcinoma with apocrine morphology that is oestrogen and progesterone receptor negative and androgen receptor positive. HER-2 status may be positive or negative. This article reviews the pathology of benign, atypical and malignant apocrine lesions of the breast, with emphasis on diagnostic criteria including an approach to evaluation of apocrine lesions on needle core biopsy, and recent advances in our understanding of invasive apocrine carcinoma.

Biological and clinical features of triple negative Invasive Lobular Carcinomas of the breast. Clinical outcome and actionable molecular alterations

Background

We report here for the first time, a comprehensive characterization of biological and clinical features of early-stage triple negative Invasive Lobular Carcinomas(TN-ILCs)

Methods

We analyzed all consecutive patients with early-stage TN-ILC operated at two reference cancer-centers between 1994 and 2012.

Primary objective was to assess the invasive disease-free survival(iDFS).

Co-primary objective was to assess biological features of TN-ILCs, including molecular intrinsic subtypes based on PAM-50 assay, expression of androgen receptor (AR) and mutational status of ERBB2-gene.

Additionally, DNA mutational status of an independent cohort of 45 TN-ILCs from three databases were analyzed, to confirm mutations in ERBB2-gene and to identify other recurrently mutated genes.

Results

Among 4152 ILCs, 74(1.8%) were TN and were analyzed.

The iDFS at 5 and 10 years of FUP were 50.4%(95%CI,38.0–61.6) and 37.2%(95%CI,25.5–48.8), respectively.

The molecular subtype was defined through PAM50-classifier for 31 out of 74 TN-ILCs: 48% were Luminal-A(15/31), 3% luminal-B(1/31), 32% HER2-enriched (10/31), and only 16% basal-like(5/31).

Luminal tumors expressed AR more frequently than non-luminal tumors (AR≥1% in 94% of luminal tumors versus 53% in non-luminal tumors; p-value = 0.001).

20% of TN-ILCs analyzed(7/35), harbored a pathogenetic and actionable mutation in the ERBB2-gene. Analysis of the independent cohort of 45 TN-ILCs from three different databases, confirmed similar percentage of pathogenetic and actionable mutations in ERBB2-gene(20%; 9/45).

Among the top 10 molecular pathways significantly enriched for recurrently mutated genes in TN-ILCs(FDR<0.05), there were ErbB-signaling and DNA-damage-response pathways.

Conclusions

TN-ILCs are rare tumors with poor prognosis. Their specific biological features require newly defined targeted therapeutic strategies

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Triple-negative ILCs are distinct from both TN-IDCs and endocrine-responsive ILC.

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TN-ILCs are enriched for actionable mutations in ErbB2 gene and DNA Damage Response genes.

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The Luminal Androgen Receptor (LAR) is the most prevalent subtype in TN-ILCs.

Survival Outcomes for Metaplastic Breast Cancer Differ by Histologic Subtype

BACKGROUND

Metaplastic breast carcinoma (MBC) is a rare, aggressive subtype of breast cancer associated with poorer overall survival than other triple-negative breast cancers. This study sought to compare survival outcomes among histologic subtypes of MBC with those of non-metaplastic triple-negative breast cancer.

METHODS

Clinicopathologic and treatment data for all patients with non-metastatic, pure MBC undergoing surgery from 1995 to 2017 and for a large cohort of patients with other types of triple-negative breast cancer during that period were collected from an institutional database. The MBC tumors were classified as having squamous, spindle, heterologous mesenchymal, or mixed histology. Survival outcomes were compared using the Kaplan-Meier method.

RESULTS

Of 132 MBC patients, those with heterologous mesenchymal MBC (n = 45) had the best 5-year overall and breast cancer-specific survival (BCSS, 88%; 95% confidence interval [CI], 0.78-0.99), whereas those with squamous MBC had the worst survival (BCSS, 56%; 95% CI, 0.32-0.79). Overall survival, BCSS, and recurrence-free survival were worse for the patients with MBC than for the patients who had non-MBC triple-negative breast cancer, with a clinicopathologically adjusted recurrence hazard ratio of 2.4 (95% CI, 1.6-3.3; p < 0.001). Of the 10 MBC patients who received neoadjuvant chemotherapy, 4 progressed while receiving treatment, and 3 had no response.

CONCLUSIONS

Metaplastic breast carcinoma is associated with worse survival than other triple-negative breast cancers. The heterologous mesenchymal subtype is associated with the best survival, whereas the squamous subtype is associated with the worst survival. These data call for research to identify therapies tailored to MBC's unique biology.

Metaplastic breast cancer: Prognostic and therapeutic considerations

INTRODUCTION

Metaplastic breast cancer (MBC) is a rare condition of breast tumor with different subtypes, considered a disease with worse prognosis; treatments and survival are often unclear and conflicting.

METHODS

We consecutively collected 153 primary MBCs of different subtypes. Breast surgery, neoadjuvant or adjuvant treatment, clinic-pathological factors, number and type of events during follow-up were considered to evaluate overall survival (OS) and invasive disease-free survival (IDFS).

RESULTS

The majority of MBC was triple-negative (TN) subtype (88.7%), G3 (95.3%), pN0 (70.6%), and with high levels of Ki-67 (93.5%). For OS and IDFS, no significant associations were seen between the different MBC subtypes. The matched triple-negative MBC (TNMBC) and ductal TNBC cohorts had similar prognosis both in terms of OS (p = .411) and IDFS (p = .981). We observed a positive trend for TNMBC patients treated in the adjuvant setting with the cyclofosfamide, methotrexate, 5-fluorouracil protocol for better OS (p = .090) and IDFS (p = .087). A poor or absent response rate was observed in the neoadjuvant setting.

CONCLUSION

Our results demonstrate that metaplastic and ductal breast cancers with TN phenotype are similar in terms of overall and disease-free survival. Metaplastic cancers are poorly responsive to neoadjuvant treatment, and in the absence of novel targeted therapies, surgical treatment remains the first choice.

Main phenotypes and histological types of breast cancer in young women attended at a reference hospital in women’s health in the city of São Paulo

It is estimated that there were 198,840 new cases of breast cancer (BC) in Brazil between 2020 and 2022. Young women who are affected by invasive BC with a triple-negative phenotype generally present more aggressive tumors that are intrinsically resistant to targeted therapies. This study evaluated the phenotypic and histological profile of BC in women up to the age of 40 years. Between 2015 and 2017, we identified 255 women with positive biopsy for carcinoma and with immunohistochemical panel, 51.76% who had a profile for luminal B (n = 132); 22.74% for triple-negative (n = 58). Of the samples, 65.88% presented histology as invasive ductal carcinoma – nonspecial type (n = 168). The results are in accordance with the literature regarding the high prevalence of triple-negative BC in young women and histological type invasive ductal carcinoma – nonspecial type.

Predicting the Survival of Triple-Negative Breast Cancer in Different Stages: A SEER Population Based Research Referring to Clinicopathological Factors

To evaluate prognosis of breast cancer patients, a total of 16,618 TNBC patients from SEER database were involved. High grade, unmarried status, tumor site were the main factors reduced OS in stage I. Black race, unmarried, large tumor size, and nodes metastasis would make worse prognosis in stage II. Compared with stage II, race and marital status had no significant effect on the prognosis in stage III. In stage IV, married status significantly improved the OS and DSS. Surgery and chemotherapy improve survival time in all of stages. Clinicopathological status correlated with the prognosis of patients with differentially staged TNBC.

Characteristics and prognosis of 17 special histologic subtypes of invasive breast cancers according to World Health Organization classification: comparative analysis to invasive carcinoma of no special type

BACKGROUND

Breast cancer is a heterogeneous disease with various histopathologic subtypes. Except for invasive carcinoma of no special type (NST), other subtypes are rare with limited data. The purpose of this study was to analyze the characteristics and prognosis of special histopathologic subtypes of breast cancer compared to NST.

METHODS

A total of 136,140 patients were analyzed using the Korean Breast Cancer Society Registry database between January 1996 and March 2019. The clinicopathologic features and survival outcomes of special type breast carcinoma were compared with those of NST.

RESULTS

The prevalence of special subtypes other than NST was 13.7% (n = 18,633). Compared to NST, patients with lobular, medullary, metaplastic, and micropapillary carcinoma had larger tumors (p < 0.001). Patients with mucinous, tubular, medullary, metaplastic, and cribriform carcinoma presented with less node metastasis (p < 0.001), contrary to patients with micropapillary carcinoma. Patients with lobular, mucinous, tubular, papillary, and cribriform carcinoma presented as luminal A subtype much more often (p < 0.001). Micropapillary carcinoma included more luminal B subtype (p < 0.001). Typically, medullary and metaplastic carcinoma included more triple-negative subtypes (p < 0.001). In survival analysis, only medullary (Hazard Ratio (HzR) 0.542, 95% CI 0.345 to 0.852, p = 0.008) and metaplastic carcinoma (HzR 1.655, 95% CI 1.317 to 2.080, p < 0.001) showed significantly different overall survival from NST by multivariate analysis.

CONCLUSION

Breast cancer had distinct clinicopathologic features according to histopathologic subtype. However, special types of breast cancer had similar survival outcomes compared to NST when adjusting for other prognostic factors, except for metaplastic carcinoma and medullary carcinoma.

Clinicopathological and genomic features of breast mucinous carcinoma

Introduction

Mucinous carcinoma (MC) of the breast is a special histological type of breast cancer. Clinicopathological characteristics and genomic features of MC is not fully understood.

Materials and methods

186,497 primary breast cancer patients from SEER database diagnosed with invasive ductal carcinoma (IDC) or MC were included. 801 primary IDC or MC patients from TCGA cohort were included for transcriptomic and genomic analysis.

Results

MC patients were older, had lower tumor grade and T and N stage, higher hormone receptor positive proportions and lower HER2 positive proportions than IDC patients. Kaplan-Meier plots showed that the breast cancer-specific survival (BCSS) of MC patients was significantly better than IDC patients (P < 0.001). However, after adjusting for clinicopathological factors, survival advantage of MC disappeared. In terms of genomic features of MC, representative upregulated genes of MC in transcriptomic level were MUC2, TFF1 and CARTPT. Upregulated pathways of MC included neurotransmitter-related pathways. Moreover, MC was featured by the amplification of 6p25.2, 6q12 and 11q12.3.

Conclusion

MC is a distinct histological subtype compared with IDC in terms of clinicopathological characteristics and genomic features. Further investigation need to be conducted to explore the formation of this specific histological subtype.

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Mucinous breast carcinoma is a distinct histological subtype with better prognosis.

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The clinicopathological characteristics of mucinous breast carcinoma contributed to its good prognosis.

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Transcriptomic and genomic features of mucinous breast carcinoma contributed to its formation.

Histologic subtyping affecting outcome of triple negative breast cancer: a large Sardinian population-based analysis

BACKGROUND

Triple Negative breast cancer (TNBC) includes a heterogeneous group of tumors with different clinico-pathological features, molecular alterations and treatment responsivity. Our aim was to evaluate the clinico-pathological heterogeneity and prognostic significance of TNBC histologic variants, comparing "special types" to high-grade invasive breast carcinomas of no special type (IBC-NST).

METHODS

This study was performed on data obtained from TNBC Database, including pathological features and clinical records of 1009 TNBCs patients diagnosed between 1994 and 2015 in the four most important Oncology Units located in different hospitals in Sardinia, Italy. Kaplan-Meier analysis, log-rank test and multivariate Cox proportional-hazards regression were applied for overall survival (OS) and disease free survival (DFS) according to TNBC histologic types.

RESULTS

TNBC "special types" showed significant differences for several clinico-pathological features when compared to IBC-NST. We observed that in apocrine carcinomas as tumor size increased, the number of metastatic lymph nodes manifestly increased. Adenoid cystic carcinoma showed the smallest tumor size relative to IBC-NST. At five-year follow-up, OS was 92.1, 100.0, and 94.5% for patients with apocrine, adenoid cystic and medullary carcinoma, respectively; patients with lobular and metaplastic carcinoma showed the worst OS, with 79.7 and 84.3%, respectively. At ten-years, patients with adenoid cystic (100.0%) and medullary (94.5%) carcinoma showed a favourable prognosis, whereas patients with lobular carcinoma showed the worst prognosis (73.8%). TNBC medullary type was an independent prognostic factor for DFS compared to IBC-NST.

CONCLUSIONS

Our study confirms that an accurate and reliable histopathologic definition of TNBC subtypes has a significant clinical utility and is effective in the therapeutic decision-making process, with the aim to develop innovative and personalized treatments.

Molecular subtypes and precision treatment of triple-negative breast cancer

Triple-negative breast cancer (TNBC) is the most aggressive breast cancer subtype. Despite the progress made in precision treatment of cancer patients, targeted treatment is still at its early stage in TNBC, and chemotherapy remains the standard treatment. With the advances in next generation sequencing technology, genomic and transcriptomic analyses have provided deeper insight into the inter-tumoral heterogeneity of TNBC. Much effort has been made to classify TNBCs into different molecular subtypes according to genetic aberrations and expression signatures and to uncover novel treatment targets. In this review, we summarized the current knowledge regarding the molecular classification of TNBC and explore the future paradigm for using molecular classification to guide the development of precision treatment and clinical practice.

Histological subtypes in triple negative breast cancer are associated with specific information on survival

Much research has focused on finding novel prognostic biomarkers for triple negative breast cancer (TNBC), whereas only scattered information about the relation between histopathological features and survival in TNBC is available. This study aims to explore the prognostic value of histological subtypes in TNBC. A multicenter retrospective TNBC cohort was established from five Dutch hospitals. All non-neoadjuvantly treated, stage I-III patients with estrogen receptor, progesterone receptor and human epidermal growth factor receptor 2 negative breast cancer diagnosed between 2006 and 2014 were included. Clinical and follow-up data (overall survival; OS, relapse free survival; RFS) were retrieved and a central histopathological review was performed. Of 597 patients included (median follow up 62.8 months, median age at diagnosis 56.0 years), 19.4% developed a recurrence. The most prevalent histological subtypes were carcinoma of no special type (NST) (88.4%), metaplastic carcinoma (4.4%) and lobular carcinoma (3.4%). Collectively, tumors of special type were associated with a worse RFS and OS compared to carcinoma NST (RFS HR 1.89; 95% CI 1.18-3.03; p = 0.008; OS HR 1.94; 95% CI 1.28-2.92; p = 0.002). Substantial differences in survival, however, were present between the different histological subtypes. In the presented TNBC cohort, special histological subtype was in general associated with less favorable survival. However, within the group of tumors of special type there were differences in survival between the different subtypes. Accurate histological examination can provide specific prognostic information that may potentially enable more personalized treatment and surveillance regimes for TNBC patients.

Analysis of the radio-pathological factors of triple negative breast cancer and determination of risk profiles

OBJECTIVE

Triple-negative tumors are the most aggressive type of breast cancer. We aimed to analyze the main radiologic and histopathologic factors of these tumors to create a risk profile.

MATERIALS AND METHODS

We analyzed data from 140 patients diagnosed with triple-negative breast cancer between January 2007 and December 2016, with follow-up through April 2018. We analyzed the following variables in the breast MRI done for staging: size, necrosis, associated findings, adenopathies, and perfusion and diffusion parameters. We analyzed the following variables in histopathologic studies of biopsy specimens: histological type, Scarf-Bloom, Ki67, and p53 in the infiltrating component as well as in the in situ component. We analyzed the following variables in histopathologic studies of positive lymph nodes and surgical specimens: size, lymphovascular/perineural invasion, and microglandular adenosis. We analyzed the relation between the radiologic and histopathologic factors and recurrence and disease-free survival.

RESULTS

MRI tumor size>25mm, non-nodular enhancement, breast edema, areola-nipple complex retraction, and lymph-node involvement were associated with recurrence and lower disease-free survival. Invasive lobular carcinoma, postsurgical size>20mm, and p53<15% were also associated with recurrence and lower disease-free survival. Histologically positive lymph nodes were associated with a greater percentage of recurrence and lymphovascular invasion and with lower disease-free survival. The multivariate analysis found that the variables MRI size>25mm, non-nodular enhancement, adenopathies on MRI, and p53 expression <15% were independent predictors of lower disease-free survival.

CONCLUSIONS

In triple-negative breast tumors, factors associated with lower disease-free survival are non-nodular enhancement, size>25mm, and adenopathies on MRI, and p53 expression <15% on histopathologic study.

Prognostic Value of Site-Specific Metastases and Surgery in De Novo Stage IV Triple-Negative Breast Cancer: A Population-Based Analysis

BACKGROUND This retrospective study aimed to evaluate the prognostic roles of distant metastatic patterns in de novo metastatic triple-negative breast cancer to explore the roles of surgery on the primary tumor and to characterize the prognostic factors of organ-specific metastasis. MATERIAL AND METHODS Data were obtained from the Surveillance, Epidemiology, and End Results program. Kaplan-Meier analyses and log-rank tests were employed to compare survival outcomes among variables. The Cox proportional hazards model was used to assess risk factors for survival. The key endpoints were overall survival and breast cancer-specific survival. RESULTS A total of 1888 patients were eligible. Distant metastatic site displayed a significant prognostic impact on survival. Using liver metastasis as the reference, overall survival was higher for bone (hazard ratio [HR] 0.770, 95% confidence interval [CI] 0.634-0.935, P=0.008) and lung (HR 0.747, 95% CI 0.612-0.911, P=0.004) metastases. Using patients with brain metastasis as the reference, patients with bone (HR 0.516, 95% CI 0.392-0.680, P<0.001), lung (HR 0.500, 95% CI 0.379-0.661, P<0.001) or liver (HR 0.670, 95% CI 0.496-0.905, P=0.009) metastases exhibited better overall survival. Single-site metastatic patients who received surgery for the primary tumor had more favorable overall survival (P<0.001) and breast cancer-specific survival (P<0.001) than those who did not. Additionally, age, insurance status, chemotherapy, and surgery affected overall survival for patients with isolated bone metastasis; chemotherapy, and surgery affected overall survival for patients with isolated lung metastasis; and insurance status, chemotherapy, and surgery affected overall survival for patients with isolated liver metastasis. CONCLUSIONS Our study verified the specific prognostic significance of distant metastatic site for metastatic triple-negative breast cancer at diagnosis. Surgery on the primary tumor significantly improved survival for patients with single distant metastasis. The identified prognostic factors contributed to evaluating the prognoses for distant metastatic triple-negative breast cancer patients.

Different Patterns of Conditional Survival of Breast Cancer Patients by Age and Histologic Types: Evidence from the Korean Nationwide Registry

BACKGROUND

Conditional relative survival (CRS), which is the survival estimate of patients who have already survived for a certain period of time after diagnosis, could provide more relevant information on the current prognosis of cancer survivors than the standard 5-year relative survival (RS). This study aimed to estimate the 5-year CRS of Korean breast cancer patients.

METHODS

We identified 145,083 breast cancer cases diagnosed between 2002 and 2013 in the Korea Central Cancer Registry. The CRS was estimated for every year after diagnosis, according to sex, age, histologic type, and stage.

RESULTS

The 5-year RS at diagnosis was 90.8%, and the 10-year RS was 85.7%. The 5-year CRS was 91.0% and 94.3% at 1 year and 5 years after diagnosis, respectively. Very young and very old patients had worse 5-year CRS after 5 years of survival than those of other age groups (92.2% in the <40-year and 92.6% in the ≥70-year groups vs. 95.4% in 40-49-year, 94.3% in 50-59-year, and 93.7% in 60-69-year groups). The 5-year CRS of metaplastic carcinoma increased from 82.0% at diagnosis to 95.2% at 5 years after diagnosis, compared with that of lobular carcinoma (from 93.1% to 92.5%). Hardly any excess mortality (5-year CRS ≥ 95%) was seen within 7 years after diagnosis.

CONCLUSIONS

This study shows that the CRS of breast cancer survivors in Korea has increased, but varies by sex, age, stage, and histologic type.

IMPACT

These findings provide more detailed information to breast cancer survivors and clinicians.

Differences in clinicopatholgic characteristics and risk of mortality between the triple positive and ER+/PR+/HER2- breast cancer subtypes

PURPOSE

This study compared the demographic and clinicopathologic characteristics and risk of mortality between the triple positive (TP) and ER+/PR+/HER2- breast cancer subtypes.

METHODS

Cases of first primary female invasive TP and ER+/PR+/HER2- breast cancer were obtained from the California Cancer Registry. Logistic regression analysis was used to compare differences in factors associated with the TP versus the ER+/PR+/HER2- subtype. Cox regression was used to compute the adjusted risk of breast cancer-specific mortality of the TP versus ER+/PR+/HER2-.

RESULTS

The odds of TP versus ER+/PR+/HER2- were higher with advanced stage, high grade, low SES, ≤ 45 years of age (OR 1.48; CI 1.40-1.55), black (OR 1.11; CI 1.02-1.21), Asian/Pacific Islander (OR 1.15; CI 1.09-1.22), and uninsured (OR 1.42; CI 1.15-1.73). Unadjusted survival analysis indicated worse survival for the TP when compared with the ER+/PR+/HER2- subtype. However, adjusted risk of mortality for the TP subtype was not statistically significantly worse than the ER+/PR+/HER2- subtype.

CONCLUSIONS

Young age, advanced stage and grade, low SES, black and API race, and lack of health insurance are more common in the TP subtype than in the ER+/PR+/HER2- subtype. However the risk of mortality between these two subtypes is similar.

Outcome for triple negative breast cancer in a retrospective cohort with an emphasis on response to platinum-based neoadjuvant therapy

Purpose

The rate of pathological complete response (pCR) for patients with triple negative breast cancer (TNBC) is increased when carboplatin is added to neo-adjuvant chemotherapy (NACT). However, while phase III trial data showing a survival benefit are awaited, carboplatin is not yet standard-of-care for TNBC. The aim of this study was to examine the rate of pCR and the outcome for those treated with carboplatin and to examine the predictors of response to therapy.

Methods

The retrospective series comprised 333 consecutive patients with TNBC (median follow-up time, 43 months). Adjuvant chemotherapy was given to 51% (n = 168) of patients and 29% (n = 97) received anthracycline–taxane NACT with carboplatin given to 9% (n = 31) of patients.

Results

Overall, 25% (n = 78) of patients experienced a breast cancer recurrence and 22% (n = 68) died from disease. A pCR breast and pCR breast/axilla was more common in those who received carboplatin (n = 18, 58% and n = 17, 55%, respectively) compared those who did not (n = 23, 36% and n = 18, 28%, respectively) (p = 0.041 and p = 0.011, respectively). By multivariable analysis, carboplatin and high tumor grade were independent predictors of pCR breast/axilla (OR_non-pCR = 0.17; 95% CI 0.06–0.54; p = 0.002; and OR_non-pCR = 0.05, 95% CI 0.01–0.27; p < 0.001, respectively). pCR breast/axilla was an independent predictor of DFS (HR_non-pCR=6.23; 95% CI 1.36–28.50; p = 0.018), metastasis-free survival (HR_non-pCR = 5.08; 95% CI 1.09–23.65; p = 0.038) and BCSS (HR_non-pCR = 8.52; 95% CI 1.09–66.64; p = 0.041).

Conclusion

Carboplatin therapy and high tumor grade are associated with a significant increase in the rate of pCR, which is an independent predictor of outcome. These data support the use of carboplatin in NACT for TNBC, while results from phase III studies are awaited.

Electronic supplementary material

The online version of this article (10.1007/s10549-018-5066-6) contains supplementary material, which is available to authorized users.