Triple-Negative Apocrine Breast Carcinoma Has Better Prognosis despite Poor Response to Neoadjuvant Chemotherapy

Neoadjuvant Chemotherapy Response in Triple-Negative Apocrine Carcinoma: Comparing Apocrine Morphology, Androgen Receptor, and Immune Phenotypes

CONTEXT.—

Apocrine differentiation and androgen receptor (AR) positivity represent a specific subset of triple-negative breast cancer (TNBC) and are often considered potential prognostic or predictive factors.

OBJECTIVE.—

To evaluate the response of TNBC to neoadjuvant chemotherapy (NAC) and to assess the impact of apocrine morphology, AR status, Ki-67 labeling index (Ki-67LI), and tumor-infiltrating lymphocytes (TILs).

DESIGN.—

A total of 232 TNBC patients who underwent NAC followed by surgical resection in a single institute were analyzed. The study evaluated apocrine morphology and AR and Ki-67LI expression via immunohistochemistry from pre-NAC biopsy samples. Additionally, pre-NAC intratumoral TILs and stromal TILs (sTILs) were quantified from biopsies using a deep learning model. The response to NAC after surgery was assessed based on residual cancer burden.

RESULTS.—

Both apocrine morphology and high AR expression correlated with lower Ki-67LI (P < .001 for both). Apocrine morphology was associated with lower postoperative pathologic complete response (pCR) rates after NAC (P = .02), but the difference in TILs between TNBC cases with and without apocrine morphology was not statistically significant (P = .09 for sTILs). In contrast, AR expression did not significantly affect pCR (P = .13). Pre-NAC TILs strongly correlated with postoperative pCR in TNBCs without apocrine morphology (P < .001 for sTILs), whereas TNBC with apocrine morphology demonstrated an indeterminate trend (P = .82 for sTILs).

CONCLUSIONS.—

Although TIL counts did not vary significantly based on apocrine morphology, apocrine morphology itself was a more reliable predictor of NAC response than AR expression. Consequently, although apocrine morphology is a rare subtype of TNBC, its identification is clinically important.

Diagnosis, Prognosis, and Treatment of Triple-Negative Breast Cancer: A Review

Triple-negative breast cancer (TNBC) has become the most aggressive and worst prognostic subtype of breast cancer due to the lack of estrogen receptor, progesterone receptor and HER2 expression. This article systematically reviews the progress in the diagnosis, prognosis and treatment of TNBC. In terms of diagnosis, imaging techniques (such as dynamic contrast-enhanced MRI and multimodality ultrasound) combined with histological and immunohistochemical detection (such as Ki-67, PD-L1 expression) can improve the early diagnosis rate; molecular markers (PIM-1, miR-522) and subtype classification (LAR, IM, BLIS, MES) provide the basis for accurate classification. Prognostic evaluation requires a combination of clinicopathologic features (tumor size, lymph node metastasis, tumor-to-stroma ratio), molecular characteristics (BRCA mutation, PD-L1 expression), and prognostic scoring systems. In treatment strategies, chemotherapy remains the basis, but efficacy and side effects need to be balanced; neoadjuvant chemotherapy can improve the pathological complete response rate, while molecular markers (such as circulating tumor cells) help predict efficacy. In terms of targeted therapy, PARP inhibitors are significantly effective in patients with BRCA mutations, and antibody drug conjugates (eg, sacituzumab govitecan) provide new options for chemoresistant patients. In immunotherapy, PD-1/PD-L1 inhibitors combined with chemotherapy significantly improved progression-free survival, especially for PD-L1-positive patients. Combined therapy, metabolic reprogramming, and individualized treatment strategies need to be further explored in the future to overcome the heterogeneity and treatment resistance of TNBC. This article emphasizes the key role of multidisciplinary collaboration and precision medicine in optimizing TNBC management and provides an important reference for clinical practice and research direction.

Rare Histological Types of Breast Cancer: A Single-Center Experience

Background: Breast carcinoma is divided into at least 21 separate histologies, according to the 2019 World Health Organization (WHO) classification. The present study is dedicated to a 5% or rarer group of all breast cancer cases. Method: In this study, we retrospectively considered the data of 4550 patients operated on for breast carcinoma at the Ankara Oncology Training and Research Hospital of the University of Health Sciences between January 2018 and February 2024. Of those cases, 401 were discovered to have rare breast cancer types. We also explored the cases by clinicopathological features, overall survival (OS), and disease-free survival (DFS). Results: Our findings revealed a total of 10 rare breast cancer types in patients explored: mucinous carcinoma, micropapillary carcinoma, papillary group carcinomas, metaplastic carcinoma, neuroendocrine carcinoma, tubular carcinoma, cribriform carcinoma, apocrine carcinoma, acinic cell carcinoma, and secretory carcinoma. While mucinous, tubular, cribriform, papillary group carcinomas, micropapillary, and secretory carcinomas are described as types associated with good prognosis, metaplastic, neuroendocrine, apocrine, and carcinomas are described as types associated with relatively poor prognosis. Conclusion: Scrutinizing the clinicopathological features of rare breast cancer types altogether may be the distinct contribution of this paper to the relevant literature and future research.

Clinicopathological significance of androgen receptor expression and tumor infiltrating lymphocytes in triple-negative breast cancer: a retrospective cohort study

BACKGROUND

Triple-negative breast cancer (TNBC) is a serious disease with limited treatment options. We explored the significance of androgen receptor (AR) expression and tumor-infiltrating lymphocytes (TILs) in predicting neoadjuvant chemotherapy (NAC) resistance in TNBC, hypothesizing that AR/TIL classification using pretreatment biopsies can identify NAC-resistant subgroups and improve the understanding of apocrine differentiation.

METHODS

This retrospective study included 156 consecutive patients with TNBC treated with NAC. AR immunostaining was defined positive if ≥ 1% of the tumor cell nuclei were stained. Stromal TIL levels were assessed, with high levels defined as ≥ 50%. Apocrine differentiation was detected using an anti-15-PGDH antibody. The pathological response to NAC was evaluated.

RESULTS

Overall, 36% (n = 56) of the patients achieved a pathological complete response (pCR). AR+/TILlow tumors had a high non-pCR rate (76%, 42/55) and were resistant to NAC. Kaplan-Meier plots showed significant differences in overall survival (OS) and distant metastasis-free survival (DMFS) among the four AR/TIL subgroups (OS: p = 0.013; DMFS: p = 0.0016). All 11 cases with some degree of apocrine differentiation were AR+/TILlow, 15-PGDH-positive, and NAC-resistant. AR+/TILlow status was significantly associated with a high likelihood of non-pCR (OR = 0.26, p = 0.009). Multivariate analysis confirmed pCR as an independent predictor of better prognosis (OS, HR = 0.13, p = 0.006; DMFS, HR = 0.15, p = 0.002), whereas AR+/TILlow status was not significantly associated with OS or DMFS.

CONCLUSIONS

AR/TIL classification using pretreatment biopsies identified TNBC subgroups with distinct NAC responses and prognoses. AR+/TILlow TNBC, including apocrine differentiation cases, were NAC-resistant, highlighting the need for alternative therapies.

Clinico-pathological factors predicting pathological response in early triple-negative breast cancer

Pathological complete response (pCR) after neoadjuvant chemoimmunotherapy (NACi) is associated with improved patient outcomes in early triple-negative breast cancer (TNBC). This study aimed to identify factors associated with pCR after NACi. This cohort included all patients with stage II-III TNBC treated with NACi who underwent surgery at Institut Curie hospitals between 08/2021-06/2023. Among 208 patients, the overall pCR rate was 70% and was similar in ER < 1% (69%) and ER-low TNBC (73%, p = 0.6). In a multivariate model, Ki-67 ≥ 30% (OR 5.19 [1.73-17.3]), centralized TILs ≥ 30% (OR = 3.08 [1.42-7.04]), absence of DCIS at initial biopsy (OR = 2.56 [1.08-6.25]) and germline mutations in homologous recombination genes (OR = 9.50 [2.37-67.7]) remained strong independent predictors of pCR. These findings may guide treatment decisions in patients with TNBC undergoing NACi. Almost all patients with germline mutations in HR genes achieved pCR, supporting de-escalation trials. We suggest that ER-low tumors should be managed as TNBC tumors.

Failure to progress: breast and prostate cancer cell lines in developing targeted therapies

Developing anticancer drugs from preclinical to clinical takes approximately a decade in a cutting-edge biomedical lab and still 97% of most fail at clinical trials. Cell line usage is critical in expediting the advancement of anticancer therapies. Yet developing appropriate cell lines has been challenging and overcoming these obstacles whilst implementing a systematic approach of utilizing 3D models that recapitulate the tumour microenvironment is prudent. Using a robust and continuous supply of cell lines representing all ethnic groups from all locales is necessary to capture the evolving tumour landscape in culture. Next, the conversion of these models to systems on a chip that can by way of high throughput cytotoxic assays identify drug leads for clinical trials should fast-track drug development while markedly improving success rates. In this review, we describe the challenges that have hindered the progression of cell line models over seven decades and methods to overcome this. We outline the gaps in breast and prostate cancer cell line pathology and racial representation alongside their involvement in relevant drug development.

Genomic characteristics of triple negative apocrine carcinoma: a comparison to triple negative breast cancer

Apocrine carcinoma is a rare breast cancer subtype. As such, the genomic characteristics of apocrine carcinoma with triple negative immunohistochemical results (TNAC), which has been treated as triple negative breast cancer (TNBC), have not been revealed. In this study, we evaluated the genomic characteristics of TNAC compared to TNBC with low Ki-67 (LK-TNBC). In the genetic analysis of 73 TNACs and 32 LK-TNBCs, the most frequently mutated driver gene in TNAC was TP53 (16/56, 28.6%), followed by PIK3CA (9/56, 16.1%), ZNF717 (8/56, 14.3%), and PIK3R1 (6/56, 10.71%). Mutational signature analysis showed enrichment of defective DNA mismatch repair (MMR)-related signatures (SBS6 and SBS21) and the SBS5 signature in TNAC, whereas an APOBEC activity-associated mutational signature (SBS13) was more prominent in LK-TNBC (Student's t test, p < 0.05). In intrinsic subtyping, 38.4% of TNACs were classified as luminal A, 27.4% as luminal B, 26.0% as HER2-enriched (HER2-E), 2.7% as basal, and 5.5% as normal-like. The basal subtype was the most dominant subtype (43.8%) in LK-TNBC (p < 0.001), followed by luminal B (21.9%), HER2-E (21.9%), and luminal A (12.5%). In the survival analysis, TNAC had a five-year disease-free survival (DFS) rate of 92.2% compared to 59.1% for LK-TNBC (P = 0.001) and a five-year overall survival (OS) rate of 95.3% compared to 74.6% for LK-TNBC (P = 0.0099). TNAC has different genetic characteristics and better survival outcomes than LK-TNBC. In particular, normal-like and luminal A subtypes in TNAC have much better DFS and OS than other intrinsic subtypes. Our findings are expected to impact medical practice for patients diagnosed with TNAC.

Triple-Negative Apocrine Carcinomas: Toward a Unified Group With Shared Molecular Features and Clinical Behavior

Triple-negative apocrine carcinomas (TNACs) are rare breast tumors with limited studies evaluating their molecular characteristics and clinical behavior. We performed a histologic, immunohistochemical, genetic, and clinicopathologic assessment of 42 invasive TNACs (1 with a focal spindle cell component) from 41 patients, 2 pure apocrine ductal carcinomas in situ (A-DCIS), and 1 A-DCIS associated with spindle cell metaplastic carcinoma (SCMBC). All TNACs had characteristic apocrine morphology and expressed androgen receptor (42/42), gross cystic disease fluid protein 15 (24/24), and CK5/6 (16/16). GATA3 was positive in most cases (16/18, 89%), and SOX10 was negative (0/22). TRPS1 was weakly expressed in a minority of tumors (3/14, 21%). Most TNACs had low Ki67 proliferation (≤10% in 67%, 26/39), with a median index of 10%. Levels of tumor infiltrating lymphocytes were low (≤10% in 93%, 39/42, and 15% in 7%, 3/42). Eighteen percent of TNACs presented with axillary nodal metastasis (7/38). No patients treated with neoadjuvant chemotherapy achieved pathologic complete response (0%, 0/10). Nearly all patients with TNAC (97%, n = 32) were without evidence of disease at the time of study (mean follow-up of 62 months). Seventeen invasive TNACs and 10 A-DCIS (7 with paired invasive TNAC) were profiled by targeted capture-based next-generation DNA sequencing. Pathogenic mutations in phosphatidylinositol 3-kinase pathway genes PIK3CA (53%) and/or PIK3R1 (53%) were identified in all TNACs (100%), including 4 (24%) with comutated PTEN. Ras-MAPK pathway genes, including NF1 (24%), and TP53 were mutated in 6 tumors each (35%). All A-DCIS shared mutations, such as phosphatidylinositol 3-kinase aberrations and copy number alterations with paired invasive TNACs or SCMBC, and a subset of invasive carcinomas showed additional mutations in tumor suppressors (NF1, TP53, ARID2, and CDKN2A). Divergent genetic profiles between A-DCIS and invasive carcinoma were identified in 1 case. In summary, our findings support TNAC as a morphologically, immunohistochemically, and genetically homogeneous subgroup of triple-negative breast carcinomas and suggest overall favorable clinical behavior.

Nomogram for predicting overall survival in patients with triple-negative apocrine breast cancer: Surveillance, epidemiology, and end results-based analysis

PURPOSE

Triple-negative apocrine carcinoma (TNAC) is a sort of triple-negative breast cancer (TNBC) that is rare and prognosis of these patients is unclear. The present study constructed an effective nomogram to assist in predicting TNAC patients overall survival (OS).

METHODS

A total of 373 TNAC patients from the surveillance, epidemiology, and end results (SEER) got extracted from 2010 to 2016 and were divided into training (n = 261) and external validation (n = 112) groups (split ratio, 7:3) randomly. A Cox regression model was utilized to creating a nomogram according to the risk factors affecting prognosis. The predictive capability of the nomogram was estimated with receiver operating characteristic (ROC) curve, calibration curve, and decision curve analysis (DCA).

RESULTS

Multivariate Cox regression analysis revealed age, surgery, chemotherapy, stage, and first malignant primary as independent predictors of OS. A prediction model was constructed and virtualized using the nomogram. The time-dependent area under the curve (AUC) showed satisfactory discrimination of the nomogram. Good consistency was shown on the calibration curves in OS between actual observations and the nomogram prediction. What's more, DCA showed that the nomogram had incredible clinical utility. Through separating the patients into groups of low and high risk group that connects with the risk system that shows a huge difference between the low-risk and high risk OS (P < 0.001).

CONCLUSION

To predict the OS in TNAC patients, the nomogram utilizing the risk stratification system that is corresponding. These tools may help to evaluate patient prognosis and guide treatment decisions.