Neoadjuvant chemotherapy for breast cancer in Italy: A Senonetwork analysis of 37,215 patients treated from 2017 to 2022.

BACKGROUND: Adoption of neoadjuvant chemotherapy (NACT) in the "real world" has been poorly investigated. Aim of this study was to examine the rate of NACT in Italy, trends over time and determinants of therapeutic choices. METHODS: Senonetwork, the recognized network of Breast Centers in Italy, has developed a voluntary national data warehouse with the aim to monitor and improve treatments quality. A retrospective analysis was conducted among 58,661 breast cancer (BC) patients treated between 2017 and 2022 by 24 high-volume Breast Centers participating in the project. RESULTS: After subset exclusion, 37,215 primary BC patients were analysed, 32,933 underwent primary-breast-surgery and 4,282 underwent NACT. From 2017 to 2022, the overall NACT incidence increased particularly for HR-/HER2+, Triple-Negative, and HR+/HER2+ BC (p < 0.001). In cN + patients the recommendation to axillary lymph-node dissection after NACT decreased over time along with an increase of <4 lymph-nodes removed (p < 0.001). Immediate breast reconstruction and indication for nipple sparing mastectomy increased significantly over time (OR = 1.10, p = 0.011 and OR 1.14, p < 0.001, respectively). On multivariate analysis, there was a trend towards an increased adoption of conservative treatment for HR-/HER2+ (p = 0.01) and Triple Negative tumors (p = 0.06). Implementation of NACT varied significantly among Breast-Centers from 3.8 to 17.7 % (p < 0.001). CONCLUSION: The impact of NACT on the subsequent surgical management is substantial and continues to evolve over time, resulting in less-extensive surgery. Even among high-volume Centers NACT implementation rate is still highly variable. Although we registered a significant increase in its use during the study period, these results need to be further improved.

The ESMO Tumour-Agnostic Classifier and Screener (ETAC-S): a tool for assessing tumour-agnostic potential of molecularly guided therapies and for steering drug development.

BACKGROUND: Advances in precision oncology led to approval of tumour-agnostic molecularly guided treatment options (MGTOs). The minimum requirements for claiming tumour-agnostic potential remain elusive. METHODS: The European Society for Medical Oncology (ESMO) Precision Medicine Working Group (PMWG) coordinated a project to optimise tumour-agnostic drug development. International experts examined and summarised the publicly available data used for regulatory assessment of the tumour-agnostic indications approved by the US Food and Drug Administration and/or the European Medicines Agency as of December 2023. Different scenarios of minimum objective response rate (ORR), number of tumour types investigated, and number of evaluable patients per tumour type were assessed for developing a screening tool for tumour-agnostic potential. This tool was tested using the tumour-agnostic indications approved during the first half of 2024. A taxonomy for MGTOs and a framework for tumour-agnostic drug development were conceptualised. RESULTS: Each tumour-agnostic indication had data establishing objective response in at least one out of five patients (ORR ≥ 20%) in two-thirds (≥4) of the investigated tumour types, with at least five evaluable patients in each tumour type. These minimum requirements were met by tested indications and may serve as a screening tool for tumour-agnostic potential, requiring further validation. We propose a conceptual taxonomy classifying MGTOs based on the therapeutic effect obtained by targeting a driver molecular aberration across tumours and its modulation by tumour-specific biology: tumour-agnostic, tumour-modulated, or tumour-restricted. The presence of biology-informed mechanistic rationale, early regulatory advice, and adequate trial design demonstrating signs of biology-driven tumour-agnostic activity, followed by confirmatory evidence, should be the principles for tumour-agnostic drug development. CONCLUSION: The ESMO Tumour-Agnostic Classifier (ETAC) focuses on the interplay of targeted driver molecular aberration and tumour-specific biology modulating the therapeutic effect of MGTOs. We propose minimum requirements to screen for tumour-agnostic potential (ETAC-S) as part of tumour-agnostic drug development. Definition of ETAC cut-offs is warranted.

ESMO Recommendations on clinical reporting of genomic test results for solid cancers.

BACKGROUND: Genomic tumour profiling has a crucial role in the management of patients with solid cancers, as it helps selecting and prioritising therapeutic interventions based on prognostic and predictive biomarkers, as well as identifying markers of hereditary cancers. Harmonised approaches to interpret the results of genomic testing are needed to support physicians in their decision making, prevent inequalities in precision medicine and maximise patient benefit from available cancer management options. METHODS: The European Society for Medical Oncology (ESMO) Translational Research and Precision Medicine Working Group assembled a group of international experts to propose recommendations for preparing clinical genomic reports for solid cancers. These recommendations aim to foster best practices in integrating genomic testing within clinical settings. After review of available evidence, several rounds of surveys and focused discussions were conducted to reach consensus on the recommendation statements. Only consensus recommendations were reported. Recommendation statements were graded in two tiers based on their clinical importance: level A (required to maintain common standards in reporting) and level B (optional but necessary to achieve ideal practice). RESULTS: Genomics reports should present key information in a front page(s) followed by supplementary information in one or more appendices. Reports should be structured into sections: (i) patient and sample details; (ii) assay and data analysis characteristics; (iii) sample-specific assay performance and quality control; (iv) genomic alterations and their functional annotation; (v) clinical actionability assessment and matching to potential therapy indications; and (vi) summary of the main findings. Specific recommendations to prepare each of these sections are made. CONCLUSIONS: We present a set of recommendations aimed at structuring genomics reports to enhance physician comprehension of genomic profiling results for solid cancers. Communication between ordering physicians and professionals reporting genomic data is key to minimise uncertainties and to optimise the impact of genomic tests in patient care.

Combining germline, tissue and liquid biopsy analysis by comprehensive genomic profiling to improve the yield of actionable variants in a real-world cancer cohort.

BACKGROUND: Comprehensive next-generation sequencing is widely used for precision oncology and precision prevention approaches. We aimed to determine the yield of actionable gene variants, the capacity to uncover hereditary predisposition and liquid biopsy appropriateness instead of, or in addition to, tumor tissue analysis, in a real-world cohort of cancer patients, who may benefit the most from comprehensive genomic profiling. METHODS: Seventy-eight matched germline/tumor tissue/liquid biopsy DNA and RNA samples were profiled using the Hereditary Cancer Panel (germline) and the TruSight Oncology 500 panel (tumor tissue/cfDNA) from 23 patients consecutively enrolled at our center according to at least one of the following criteria: no available therapeutic options; long responding patients potentially fit for other therapies; rare tumor; suspected hereditary cancer; primary cancer with high metastatic potential; tumor of unknown primary origin. Variants were annotated for OncoKB and AMP/ASCO/CAP classification. RESULTS: The overall yield of actionable somatic and germline variants was 57% (13/23 patients), and 43.5%, excluding variants previously identified by somatic or germline routine testing. The accuracy of tumor/cfDNA germline-focused analysis was demonstrated by overlapping results of germline testing. Five germline variants in BRCA1, VHL, CHEK1, ATM genes would have been missed without extended genomic profiling. A previously undetected BRAF p.V600E mutation was emblematic of the clinical utility of this approach in a patient with a liver undifferentiated embryonal sarcoma responsive to BRAF/MEK inhibition. CONCLUSIONS: Our study confirms the clinical relevance of performing extended parallel tumor DNA and cfDNA testing to broaden therapeutic options, to longitudinally monitor cfDNA during patient treatment, and to uncover possible hereditary predisposition following tumor sequencing in patient care.

Triple-negative breast carcinomas of low malignant potential: review on diagnostic criteria and differential diagnoses.

Triple-negative breast carcinomas constitute a wide spectrum of lesions, mostly being highly aggressive. Nevertheless, some special histologic subtypes can have low malignant potential. The purpose of the present paper is to review diagnostic criteria and prognostic parameters of breast neoplasms of special histotypes. Specifically, adenoid cystic carcinoma, adenomyoepithelioma, acinic cell carcinoma, mucoepidermoid carcinoma, tall cell carcinoma with reverse polarity, and secretory carcinoma will be discussed. For each tumour, definition and morphological and molecular features, together with prognostic parameters, will be presented. Paradigmatic cases will be illustrated.

ESMO recommendations on the standard methods to detect NTRK fusions in daily practice and clinical research.

BACKGROUND: NTRK1, NTRK2 and NTRK3 fusions are present in a plethora of malignancies across different histologies. These fusions represent the most frequent mechanism of oncogenic activation of these receptor tyrosine kinases, and biomarkers for the use of TRK small molecule inhibitors. Given the varying frequency of NTRK1/2/3 fusions, crucial to the administration of NTRK inhibitors is the development of optimal approaches for the detection of human cancers harbouring activating NTRK1/2/3 fusion genes. MATERIALS AND METHODS: Experts from several Institutions were recruited by the European Society for Medical Oncology (ESMO) Translational Research and Precision Medicine Working Group (TR and PM WG) to review the available methods for the detection of NTRK gene fusions, their potential applications, and strategies for the implementation of a rational approach for the detection of NTRK1/2/3 fusion genes in human malignancies. A consensus on the most reasonable strategy to adopt when screening for NTRK fusions in oncologic patients was sought, and further reviewed and approved by the ESMO TR and PM WG and the ESMO leadership. RESULTS: The main techniques employed for NTRK fusion gene detection include immunohistochemistry, fluorescence in situ hybridization (FISH), RT-PCR, and both RNA-based and DNA-based next generation sequencing (NGS). Each technique has advantages and limitations, and the choice of assays for screening and final diagnosis should also take into account the resources and clinical context. CONCLUSION: In tumours where NTRK fusions are highly recurrent, FISH, RT-PCR or RNA-based sequencing panels can be used as confirmatory techniques, whereas in the scenario of testing an unselected population where NTRK1/2/3 fusions are uncommon, either front-line sequencing (preferentially RNA-sequencing) or screening by immunohistochemistry followed by sequencing of positive cases should be pursued.

Pathological non-response to chemotherapy in a neoadjuvant setting of breast cancer: an inter-institutional study.

To identify markers of non-response to neoadjuvant chemotherapy (NAC) that could be used in the adjuvant setting. Sixteen pathologists of the European Working Group for Breast Screening Pathology reviewed the core biopsies of breast cancers treated with NAC and recorded the clinico-pathological findings (histological type and grade; estrogen, progesterone receptors, and HER2 status; Ki67; mitotic count; tumor-infiltrating lymphocytes; necrosis) and data regarding the pathological response in corresponding surgical resection specimens. Analyses were carried out in a cohort of 490 cases by comparing the groups of patients showing pathological complete response (pCR) and partial response (pPR) with the group of non-responders (pathological non-response: pNR). Among other parameters, the lobular histotype and the absence of inflammation were significantly more common in pNR (p < 0.001). By ROC curve analyses, cut-off values of 9 mitosis/2 mm(2) and 18% of Ki67-positive cells best discriminated the pNR and pCR + pPR categories (p = 0.018 and < 0.001, respectively). By multivariable analysis, only the cut-off value of 9 mitosis discriminated the different response categories (p = 0.036) in the entire cohort. In the Luminal B/HER2- subgroup, a mitotic count <9, although not statistically significant, showed an OR of 2.7 of pNR. A lobular histotype and the absence of inflammation were independent predictors of pNR (p = 0.024 and <0.001, respectively). Classical morphological parameters, such as lobular histotype and inflammation, confirmed their predictive value in response to NAC, particularly in the Luminal B/HER2- subgroup, which is a challenging breast cancer subtype from a therapeutic point of view. Mitotic count could represent an additional marker but has a poor positive predictive value.

Integrative molecular and functional profiling of ERBB2-amplified breast cancers identifies new genetic dependencies.

Overexpression of the receptor tyrosine kinase ERBB2 (also known as HER2) occurs in around 15% of breast cancers and is driven by amplification of the ERBB2 gene. ERBB2 amplification is a marker of poor prognosis, and although anti-ERBB2-targeted therapies have shown significant clinical benefit, de novo and acquired resistance remains an important problem. Genomic profiling has demonstrated that ERBB2+ve breast cancers are distinguished from ER+ve and 'triple-negative' breast cancers by harbouring not only the ERBB2 amplification on 17q12, but also a number of co-amplified genes on 17q12 and amplification events on other chromosomes. Some of these genes may have important roles in influencing clinical outcome, and could represent genetic dependencies in ERBB2+ve cancers and therefore potential therapeutic targets. Here, we describe an integrated genomic, gene expression and functional analysis to determine whether the genes present within amplicons are critical for the survival of ERBB2+ve breast tumour cells. We show that only a fraction of the ERBB2-amplified breast tumour lines are truly addicted to the ERBB2 oncogene at the mRNA level and display a heterogeneous set of additional genetic dependencies. These include an addiction to the transcription factor gene TFAP2C when it is amplified and overexpressed, suggesting that TFAP2C represents a genetic dependency in some ERBB2+ve breast cancer cells.

Changes in breast cancer biomarkers in the IGF1R/PI3K pathway in recurrent breast cancer after tamoxifen treatment.

Development of resistance to the antioestrogen tamoxifen occurs in a large proportion of patients with oestrogen receptor-positive (ER+) breast cancer and is an important clinical challenge. While loss of ER occurs in c.20% of tamoxifen-resistant tumours, this cannot be the sole explanation for tamoxifen treatment failure. PI3K pathway activation, including by insulin-like growth factor receptor 1 (IGF1R), has been implicated in some resistance models. The primary aim was to determine whether evidence exists in clinical breast cancer for a role of IGF1R and/or the PI3K pathway, in acquisition of resistance to tamoxifen. Invasive primary and recurrent tamoxifen-resistant tumours from the same patient (n=77) were assessed for changes in ER, progesterone receptor (PgR), human epidermal growth factor receptor 2 (HER2), IGF1R, stathmin, PTEN expression and PIK3CA mutations where possible. ER and PgR levels were significantly reduced at recurrence with 22 and 45%, respectively, showing negative status at this time. Acquisition of HER2 overexpression occurred in 6% of cases. IGF1R expression was significantly reduced in both ER+ and ER- recurrences and stathmin levels increased. A positive association between stathmin and IGF1R emerged in recurrent samples, despite their opposing relationships with ER, suggesting some coalescence of their activities may be acquired. The data confirm loss of ER and PgR and gain of HER2 in some tamoxifen-resistant tumours. There is no evidence for IGF1R gain in tamoxifen resistance; increases in stathmin levels suggest that activation of the PI3K pathway may have contributed, but PTEN loss and PIK3CA hotspot mutations were relatively rare.

Chemotherapy with or without trastuzumab.

The prognosis of pT1N0M0/stage I breast cancer has generally been considered so favourable that these patients are not routinely offered adjuvant systemic therapy. However, biological heterogeneity within pT1N0M0 dictates diverse outcomes within the subgroup. HER2 gene amplification or protein overexpression is uncommon in pT1N0M0 disease, but, when present, is clearly associated with a higher risk of recurrence. The role of anti-HER2 therapy in these patients is controversial. Few women with node-negative, small tumours were included in the adjuvant trastuzumab trials. There are no robust data on trastuzumab in this patient subset, although subgroup analyses suggest that proportional benefits are independent of T and N. With current guidelines and scheduling, committing to adjuvant trastuzumab involves concurrent chemotherapy, 1 year of treatment and potential cardiotoxicity. A further challenge with anti-HER2 therapy is the potential benefit in patients with demonstrable HER2 positivity within a predominantly HER2-negative tumour. The decision for therapy requires a yes/no answer, but HER2 status derives from a continuum of gene copy number and protein expression. The diagnostic threshold is made more complex by heterogeneity of the HER2 status within a tumour. This review focuses on available data for HER2-positive pT1N0M0 disease and explores the significance of intratumoural HER2 heterogeneity.

The genomic profile of HER2-amplified breast cancers: the influence of ER status.

Expression profiling studies have suggested that HER2-amplified breast cancers constitute a heterogeneous group that may be subdivided according to their ER status: HER2-amplified ER-positive breast carcinomas that fall into the luminal B cluster; and HER2-amplified ER-negative cancers which form a distinct molecular subgroup, known as the erbB2 or HER2 subgroup. ER-negative breast cancer differs significantly from ER-positive disease in the pattern, type, and complexity of genetic aberrations. Here we have compared the genomic profiles of ER-positive and ER-negative HER2-amplified cancers using tiling path microarray-based comparative genomic hybridization (aCGH). Validation of the differentially amplified regions was performed in an independent series of 70 HER2-amplified breast cancers. Although HER2-amplified cancers had remarkably complex patterns of molecular genetic aberrations, ER-positive and ER-negative HER2-amplified breast carcinomas shared most molecular genetic features as defined by aCGH. Genome-wide Fisher's exact test analysis revealed that less than 1.5% of the genome was significantly differentially gained or lost in ER-positive versus ER-negative HER2-amplified cancers. However, two regions of amplification were significantly associated with ER-positive carcinomas, one of which mapped to 17q21.2 and encompassed GJC1, IGFBP4, TNS4, and TOP2A. Chromogenic in situ hybridization analysis of an independent validation series confirmed the association between ER status and TOP2A amplification. In conclusion, although hormone receptor status does not determine the overall genetic profile of HER2-amplified breast cancers, specific genetic aberrations may be characteristic of subgroups of HER2 breast cancers.

ESR1 amplification in endometrial carcinomas: hope or hyperbole?

The ESR1 gene maps 6q25 and encodes for oestrogen receptor alpha, which has been shown to play a pivotal role in the development of breast and endometrial cancer. It has recently been reported that oestrogen receptor alpha expression may be driven in some cases by ESR1 gene amplification and that this phenomenon may be an early event in breast and endometrial carcinogenesis. Although copy number gains of 6q have been reported by several groups, their prevalence, association with oestrogen receptor alpha expression, and clinical implications have been a matter of controversy. Here we discuss the key issues regarding the methods employed in the identification of ESR1 amplification, and briefly review the current literature and recent controversies on the subject of ESR1 amplification in endometrial and breast cancers.

Hereditary breast cancer: from molecular pathology to tailored therapies.

Hereditary breast cancer accounts for up to 5-10% of all breast carcinomas. Recent studies have demonstrated that mutations in two high-penetrance genes, namely BRCA1 and BRCA2, are responsible for about 16% of the familial risk of breast cancer. Even though subsequent studies have failed to find another high-penetrance breast cancer susceptibility gene, several genes that confer a moderate to low risk of breast cancer development have been identified; moreover, hereditary breast cancer can be part of multiple cancer syndromes. In this review we will focus on the hereditary breast carcinomas caused by mutations in BRCA1, BRCA2, Fanconi anaemia (FANC) genes, CHK2 and ATM tumour suppressor genes. We describe the hallmark histological features of these carcinomas compared with non-hereditary breast cancers and show how an accurate histopathological diagnosis may help improve the identification of patients to be screened for mutations. Finally, novel therapeutic approaches to treat patients with BRCA1 and BRCA2 germ line mutations, including cross-linking agents and PARP inhibitors, are discussed.

Nestin is expressed in basal-like and triple negative breast cancers.

AIMS: To analyse the distribution of nestin expression in different breast tumours and to determine the prognostic impact of nestin expression. METHODS: Nestin expression was immunohistochemically analysed in a cohort of 245 invasive breast cancer patients treated with therapeutic surgery followed by anthracycline-based chemotherapy using a semi-quantitative scoring system. RESULTS: Nestin was exclusively expressed in grade III breast carcinoma and preferentially expressed in basal-like and triple negative cancers. Nestin-positive tumours displayed high proliferation rates and p53 nuclear expression. Lymph-node positive patients with nestin-positive cancers had a shorter breast cancer specific survival; however nestin was not an independent prognostic factor on multivariate analysis. CONCLUSIONS: Nestin expression is preferentially found in basal-like and triple negative breast carcinomas. Further studies are warranted to define the biological role played by nestin in these subgroups of breast cancers.

Genomic and immunophenotypical characterization of pure micropapillary carcinomas of the breast.

Pure invasive micropapillary carcinoma (MPC) is a special histological type that accounts for 0.7-3% of all breast cancers. MPC has a distinctive growth pattern and a more aggressive clinical behaviour than invasive ductal carcinomas of no special type (IDC-NSTs). To define the molecular characteristics of MPCs, we profiled a series of 12 MPCs and 24 grade and oestrogen receptor (ER)-matched IDC-NSTs using high-resolution microarray comparative genomic hybridization (aCGH). In addition, we generated a tissue microarray containing a series of 24 MPCs and performed immunohistochemical analysis with ER, PR, Ki-67, HER2, CK5/6, CK14, CK17, EGFR, topoisomerase-IIalpha, cyclin D1, caveolin-1, E-cadherin, and beta-catenin antibodies. In situ hybridization probes were employed to evaluate the prevalence of amplification of HER2, TOP2A, EGFR, CCND1, MYC, ESR1, and FGFR1 genes. aCGH analysis demonstrated that MPCs significantly differed from IDC-NSTs at the genomic level. Gains of 1q, 2q, 4p, 6p, 6q23.2-q27, 7p, 7q, 8p, 8q, 9p, 10p, 11q, 12p, 12q, 16p, 17p, 17q, 19p, 20p, 20q, and 21q, and losses of 1p, 2p, 6q11.1-q16.3, 6q21-q22.1, 9p, 11p, 15q, and 19q were more prevalent in MPCs. High-level gains/amplifications of 8p12-p11, 8q12, 8q13, 8q21, 8q23, 8q24, 17q21, 17q23, and 20q13 were significantly associated with MPCs. A comparison between 24 MPCs and a series of 48 grade and ER-matched IDC-NSTs revealed that high cyclin D1 expression, high proliferation rates, and MYC (8q24) amplification were significantly associated with MPCs. Our results demonstrate that MPCs have distinct histological features and molecular genetic profiles supporting the contention that they constitute a distinct pathological entity.

Is acinic cell carcinoma a variant of secretory carcinoma? A FISH study using ETV6'split apart' probes.

AIMS: Acinic cell carcinomas (ACCs) and secretory carcinomas (SCs) of the breast are rare, low-grade malignancies that preferentially affect young female patients. Owing to the morphological and immunohistochemical similarities between these lesions, they have been proposed to be two morphological variants of the same entity. It has been demonstrated that SCs of the breast consistently harbour the t(12;15)ETV6-NTRK3 translocation. The aim was to determine whether ACCs also harbour ETV6 gene rearrangements and are thus variants of SCs. METHODS AND RESULTS: Using the ETV6 fluorescence in situ hybridization DNA Probe Split Signal (Dako), the presence of ETV6 rearrangements in three SCs and six ACCs was investigated. Cases were considered as harbouring an ETV6 gene rearrangement if >10% of nuclei displayed 'split apart signals' (i.e. red and green signals were separated by a distance greater than the size of two hybridization signals). Whereas the three SCs displayed ETV6 split apart signals in >10% of the neoplastic cells, no ACC showed any definite evidence of ETV6 gene rearrangement. CONCLUSIONS: Based on the lack of ETV6 rearrangements in ACCs, our results strongly support the concept that SCs and ACCs are distinct entities and should be recorded separately in breast cancer taxonomy schemes.

Traditional urinary cytology and tyrosinase RT-PCR in metastatic melanoma patients: correlation with clinical status.

BACKGROUND: The finding of a suspicious urinary cytology is not uncommon in melanoma patients, in as much as morphology alone is often unable to distinguish the variable cytological features of melanoma cells. To date, although tyrosinase reverse transcription (RT)-PCR assay has been used to identify melanoma cells in peripheral blood and tissues, this method has not been applied to the analysis of urine samples. METHODS: RT-PCR mRNA tyrosinase expression was analysed in 79 urine samples from patients with metastatic melanoma and correlated with standard morphology/immunocytology. The results were compared with the disease course and presence of genito-urinary involvement. RESULTS: A positive RT-PCR expression was found in 18/79 urine samples from patients with metastases; four of the 18 patients had positive cytology, nine had atypical cytology, and five had negative cytology. Genito-urinary metastases were demonstrated in 27.8% tyrosinase-positive patients but in only 9.8% of the negative patients. The majority of tyrosinase-positive patients had a progressive disease unresponsive to chemotherapy. Urine samples from 20 patients with non-melanoma cancer and 20 healthy subjects were all negative. CONCLUSIONS: Our data demonstrate the higher sensitivity of RT-PCR compared with standard cytology in detection of urinary melanoma cells, and suggest that this assay could be used as an additional tool in the presence of negative or suspicious cytology.

Forkhead box A1 expression in breast cancer is associated with luminal subtype and good prognosis.

AIMS: Forkhead box A1 (FOXA1) is a forkhead family transcription factor expressed in breast cancer cells. It is essential for optimal expression of approximately 50% of oestrogen receptor (ER)-related genes. This study explored the FOXA1 relationship with luminal and basal breast cancer subtypes, proliferation markers, and survival in breast cancer patients who had received similar treatment. METHODS: A tissue microarray comprising tumours from 245 invasive breast cancer patients with 67 months of median follow-up was analysed for FOXA1 expression by immunohistochemistry. Interpretable FOXA1 expression, obtained in 184 patients, was analysed along with other variables such as tumour grade, size, nodal status, ER, progesterone receptor, HER2/neu, proliferation and basal markers. RESULTS: FOXA1 expression (score >3) was seen in 139 of 184 breast cancers. It correlated positively with ERalpha (p<0.0001), progesterone receptor (p<0.0001), and luminal subtype (p<0.0001); negatively with basal subtype (p<0.0001), proliferation markers and high histological grade (p = 0.0327). Univariate analysis showed nodal status, tumour grade, ER, progesterone receptor, FOXA1, basal markers and p53 as significant predictors of overall survival. Multivariate analysis showed that only nodal status (p = 0.0006) and ER (p = 0.0017) were significant predictors of OS. In luminal subtype patient subgroup, FOXA1 expression was associated with better survival (p = 0.0284) on univariate analysis. CONCLUSION: Based on this study in patients treated with surgery followed by adjuvant anthracycline-based chemotherapy, FOXA1 expression is associated with good prognosis. It correlates with luminal subtype breast cancer, and could possibly serve as a clinical marker for luminal subtype A. Prognostic ability of FOXA1 in these low-risk breast cancers may prove to be useful in treatment decision making.

The expression of Wilms' tumour-1 and Ca125 in invasive micropapillary carcinoma of the breast.

AIM: Metastases from ovarian serous papillary carcinoma to the breast and primary invasive micropapillary carcinoma of the breast are histologically similar. The distinction is clinically important to ensure appropriate management. Wilms' tumour-1 (WT1) and Ca125 are frequently expressed in serous papillary carcinomas, and uncommonly in unselected mammary carcinomas. One previous study found Ca125 expression in 69% of invasive micropapillary carcinomas. The aim was to assess the frequency of expression of WT1 and Ca125 in invasive micropapillary carcinoma. METHODS AND RESULTS: Twenty-five of 34 invasive micropapillary carcinomas showed no nuclear expression of WT1. The remaining nine tumours showed weak to moderate immunoreactivity in 1-10% of nuclei. Six of these nine tumours also contained ductal carcinoma in situ, which expressed WT1 in five of the six. Membranous or cytoplasmic expression of Ca125 was found in seven tumours. CONCLUSION: Nuclear WT1 expression is present in a minority of invasive micropapillary carcinomas and, when present, expression is focal. The frequency of expression of Ca125 was similar to the results in unselected mammary carcinoma. Thus, these markers are useful members of the immunohistochemical panel for the distinction of mammary invasive micropapillary carcinoma from ovarian serous papillary carcinoma.

Patients with advanced stage breast carcinoma immunoreactive to biotinylated Herceptin are most likely to benefit from trastuzumab-based therapy: an hypothesis-generating study.

BACKGROUND: Biotin-labeled trastuzumab (BiotHER) can be used to test for HER2 by immunohistochemistry. We previously showed that BiotHER immunoreactivity is highly correlated with HER2 amplification and indicated that it could be associated with better clinical outcome in advanced breast cancer patients receiving trastuzumab. PATIENTS AND METHODS: Tumor specimens and clinical information from 234 patients who received trastuzumab-based treatments were collected from 10 institutions. HER2 amplification and BiotHER immunoreactivity were assessed centrally. The effect of BiotHER positivity on response rate (RR), time to progression and survival were studied by univariate and multivariate analysis in patients presenting HER2-amplified breast cancer. The pathologic reviews of the assays were blinded to patient outcomes. RESULTS: BiotHER was positive in 109/194 (56%) HER2-amplified breast cancers and in one not amplified tumor. RRs were 74% [95% (confidence interval) CI 64%-81%] and 47% (95% CI 36%-58%) in BiotHER-positive and -negative tumors, respectively (P < 0.001). BiotHER immunoreactivity was independently associated with increased probability of tumor response (odds ratio 3.848; 95% CI 1.952-7.582), with reduced risk of disease progression [hazard ratio (HR) 0.438; 95% CI 0.303-0.633] and with reduced risk of death (HR 0.566; 95% CI 0.368-0.870) by multivariate analysis. CONCLUSION: The results support a role for BiotHER testing in better tailoring trastuzumab-based treatments in patients with advanced HER2-amplified breast cancers.