Concordance between HER-2 and steroid hormone receptor expression between primary breast cancer, sentinel node metastases, and isolated tumor cells

Human epidermal growth factor receptor 2 (HER2) status in breast cancer: practice points and challenges

Human epidermal growth factor receptor 2 (HER2)-enriched breast cancer benefits significantly from anti-HER2 targeted therapies. This highlights the critical need for precise HER2 immunohistochemistry (IHC) interpretation serving as a triage tool for selecting patients for anti-HER2 regimens. Recently, the emerging eligibility of patients with HER2-low breast cancers for a novel HER2-targeted antibody-drug conjugate (T-DXd) adds challenges to HER2 IHC scoring interpretation, notably in the 0-1+ range, which shows high interobserver and interlaboratory staining platform variability. In this review, we navigate evolving challenges and suggest practical recommendations for HER2 IHC interpretation.

Discordance in ER, PR, HER2, and Ki-67 Expression Between Primary and Recurrent/Metastatic Lesions in Patients with Primary Early Stage Breast Cancer and the Clinical Significance: Retrospective Analysis of 75 Cases

Background: The objective was to explore the discordance in the expression of the estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2), and Ki-67 between primary and recurrent/metastatic lesions in patients with early stage breast cancer as well as the prognostic impact.

Method: Patients with early-stage primary breast cancer and confirmed recurrence/metastasis at Peking Union Medical College Hospital between January 2005 and August 2018 were screened. The details of discordance in each parameter between primary and recurrent/metastatic lesions and progression were recorded. Regression and survival analysis were applied to determine the association and clinical impact of the discordance.

Results: We evaluated 75 patients. The discordance rate of ER, PR, HER2, and Ki-67 expression was 9.3, 14.7, 14.7, and 21.5%, respectively. Additionally, 66.7, 11.8, 14.3, and 0% of patients with Luminal A, Luminal B, HER2, and triple-negative primary tumors presented with a different subtype for the recurrent/metastatic tumors, respectively. No statistical difference in progression-free survival was observed according to the subtype of the recurrent or metastatic breast cancer (p > 0.05). Among 69 patients for whom treatment was adjusted after recurrence or metastasis, 66 patients remained recurrence-free during the follow-up period.

Conclusion: For patients with early-stage breast cancer, the ER, PR, HER2, and Ki-67 expression profile for recurrent/metastatic tumors does not always match that of the primary tumor. After adjusting treatment according to the receptor expression in recurrent/metastatic lesions, most patients remained progression-free during the follow-up period.

Discordance of immunohistochemical markers between primary and recurrent or metastatic breast cancer: A retrospective analysis of 107 cases

There is a discordance in the immunohistochemical markers between primary breast cancer and recurrent or metastatic breast cancer. This study aimed to assess the recent trends and prognostic features in the treatment of recurrent or metastatic breast cancerOverall, 107 patients were identified from January 2001 to August 2018 at the Peking Union Medical College Hospital, Beijing, and People's Republic of China to obtain a cohort of breast carcinoma patients who were confirmed to have recurrent or metastatic breast cancer by histopathology. We evaluated patient and tumor characteristics and examined the relationships between these factors and prognosis.The estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor-2 (HER2) positivity, and Ki67 index in primary breast cancer were 63.6% (68/107), 58.9% (63/107), 19.8% (21/106) and 75.8% (75/99), respectively, while those in recurrent or metastatic lesions were 60.6% (65/107) (P = .672), 46.7% (50/107) (P = 0.013), 23.8% (25/105) (P = 0.482)and 83.5%(81/97)(P = 0.178), respectively. The discordance rate of HER2 expression was 10.6% (11/104), while that of PR expression was 23.3% (21/90). HER2 was the most stable biomarker. The discordance rates for luminal A and HER2 were as high as 100% and 25%, respectively, while the luminal B and triple negative values were as low as 8.3% and 5.3%, respectively.ER and PR positivity and the Ki-67 index tended to increase due to recurrence or metastases; however, the discordance for PR and Ki-67 was high. PR is more variable than ER in the expression of primary and recurrent or metastatic breast cancer. The expression of HER2 receptor was the most stable and the discordance rate of triple negative breast cancer was the lowest. Therefore, although changes in biomarkers are due to recurrence or metastasis, pathological confirmation and exploration of markers are very important.

Cysts mark the early stage of metastatic tumor development in non-small cell lung cancer

Identifying metastatic tumor growth at an early stage has been one of the biggest challenges in the treatment of lung cancer. By genetic lineage tracing approach in a conditional model of Non-Small Cell Lung Cancer (NSCLC) in mice, we demonstrate that cystic lesions represent an early stage of metastatic invasion. We generated a mouse model for NSCLC which incorporated a heritable DsRed fluorescent tag driven by the ubiquitous CAG promoter in the alveolar type II cells of the lung. We found early cystic lesions in a secondary organ (liver) that lacked the expression of bona fide lung makers namely Scgb1a1 and surfactant protein C Sftpc and were DsRed positive hence identifying lung as their source of origin. This demonstrates the significant potential of alveolar type II cells in orchestrating the process of metastasis, rendering it as one of the target cell types of the lung of therapeutic importance in human NSCLC.

Estrogen, progesterone, and HER2/neu receptor discordance between primary and metastatic breast tumours-a review

Discordance in estrogen (ER), progesterone (PR), and HER2/neu status between primary breast tumours and metastatic disease is well recognized. In this review, we highlight how receptor discordance between primary tumours and paired metastasis can help elucidate the mechanism of metastasis but can also effect patient management and the design of future trials. Discordance rates and ranges were available from 47 studies (3384 matched primary and metastatic pairs) reporting ER, PR, and HER2/neu expression for both primary and metastatic sites. Median discordance rates for ER, PR, and HER2/neu were 14 % (range 0-67 %, IQR 9-25 %), 21 % (range 0-62 %, IQR 15-41 %), and 10 % (range 0-44 %, IQR 4-17 %), respectively. Loss of receptor expression was more common (9.17 %) than gain (4.51 %). Discordance rates varied amongst site of metastasis with ER discordance being highest in bone metastases suggesting that discordance is a true biological phenomenon. Discordance rates vary for both the biomarker and the metastatic site. Loss of expression is more common than gain. This can affect patient management as it can lead to a reduction in both the efficacy and availability of potential therapeutic agents. Future studies are recommended to explore both the mechanisms of discordance as well as its impact on patient outcome and management.

Correlation of Expression of Breast Biomarkers in Primary and Metastatic Breast Carcinomas: A Single-Institution Experience

OBJECTIVE

Changes in the status of estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2) in metastatic breast carcinomas are frequently reported. We examined the change in the status of biomarkers in metastatic breast carcinomas.

STUDY DESIGN

This study cohort was composed of 137 metastatic breast carcinomas (58 surgical and 79 cytological specimens) with existing primary tumors during a study period from 2013 to 2015.

RESULTS

The overall change rates in metastases were 9, 21 and 6% for ER, PR and HER2, respectively. All changes were from positive in the primary tumor to negative in the metastases. The ER change rate was significantly higher in the cytological than in the surgical metastases. Six of 14 cytological metastases with positive HER2 in primary tumors showed a change in HER2 status, including 5 fluid specimens and 1 fine-needle aspiration (FNA); the other 8 had no change in HER2 status, and included 7 FNAs and 1 fluid specimen.

CONCLUSION

The significant percentage of cases with a change in biomarker status supports the recommendation by the College of American Pathologists to test breast biomarkers in metastases. HER2 status change was mostly identified in fluid specimens; however, the small sample size in our cohort and the fact that HER2 fluorescence in situ hybridization was not performed may warrant further studies.

HER2 loss in HER2-positive gastric or gastroesophageal cancer after trastuzumab therapy: Implication for further clinical research

Mechanisms of acquired resistance to trastuzumab-based treatment in gastric cancer are largely unknown. In this study, we analyzed 22 pairs of tumor samples taken at baseline and post-progression in patients receiving chemotherapy and trastuzumab for advanced HER2-positive [immunohistochemistry (IHC) 3+ or 2+ with in-situ hybridization (ISH) amplification] gastric or gastroesophageal cancers. Strict clinical criteria for defining acquired trastuzumab resistance were adopted. Loss of HER2 positivity and loss of HER2 over-expression were defined as post-trastuzumab IHC score <3+ and absence of ISH amplification, and IHC "downscoring" from 2+/3+ to 0/1+, respectively. HER2 IHC was always performed, while ISH was missing in 3 post-progression samples. Patients with initial HER2 IHC score 3+ and 2+ were 14 (64%) and 8 (36%), respectively. Loss of HER2 positivity and HER2 over-expression was observed in 32 and 32% samples, respectively. The chance of HER2 loss was not associated with any of the baseline clinicopathological variables. The only exception was in patients with initial IHC score 2+ versus 3+, for both endpoints of HER2 positivity (80 vs. 14%; p = 0.008) and HER2 over-expression (63 vs. 14%; p = 0.025). As already shown in breast cancer, loss of HER2 may be observed also in gastric cancers patients treated with trastuzumab-based chemotherapy in the clinical practice. This phenomenon may be one of the biological reasons explaining the failure of anti-HER2 second-line strategies in initially HER2-positive disease.

Detecting Tumor Metastases: The Road to Therapy Starts Here

Metastasis is the complex process by which primary tumor cells migrate and establish secondary tumors in an adjacent or distant location in the body. Early detection of metastatic disease and effective therapeutic options for targeting these detected metastases remain impediments to effectively treating patients with advanced cancers. If metastatic lesions are identified early, patients might maximally benefit from effective early therapeutic interventions. Further, monitoring patients whose primary tumors are effectively treated for potential metastatic disease onset is also highly valuable. Finally, patients with metastatic disease can be monitored for efficacy of specific therapeutic interventions through effective metastatic detection techniques. Thus, being able to detect and visualize metastatic lesions is key and provides potential to greatly improve overall patient outcomes. In order to achieve these objectives, researchers have endeavored to mechanistically define the steps involved in the metastatic process as well as ways to effectively detect metastatic progression. We presently overview various preclinical and clinical in vitro and in vivo assays developed to more efficiently detect tumor metastases, which provides the foundation for developing more effective therapies for this invariably fatal component of the cancerous process.

HER-2, ER, PR status concordance in primary breast cancer and corresponding metastatic lesion in lymph node in Chinese women

AIMS AND BACKGROUND

To compare the expression of estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER-2) in the primary site and the metastatic lesion of lymph nodes in invasive breast cancer for investigating whether the expression of these biomarkers in the primary site could act as a surrogate to the lymphatic metastatic lesion in the same patient.

METHODS

In lymphatic metastatic lesion and corresponding primary lesion of 107 cases of invasive breast cancer, ER and PR statuses were assessed by immunohistochemistry (IHC). HER-2 expression level was evaluated by IHC and/or fluorescence in situ hybridization (FISH).

RESULTS

In the primary lesions, 43.9% were ER positive; 46.7% were PR positive; 34.6% were HER-2 positive. In corresponding lymphatic metastatic lesions, the HER-2 status was concordant in 90 patients; 9 patients were diagnosed positive in metastatic lesion while negative in primary lesion; 8 patients were negative in metastatic lesion while positive in primary site (agreement, 84.1%; κ=0.647). A change in ER status was observed in 24 cases: 17 cases positive in metastatic site while negative in primary site; 7 cases negative in metastatic site while positive in primary site (agreement, 77.6%; κ=0.534). PR status discordance between the primary lesion and the metastatic regional lymph nodes was reported in 19 cases (agreement, 82.2%; κ=0.640).

CONCLUSIONS

This study revealed that there was only a moderate concordance of ER, PR and HER-2 status between primary tumors and metastatic lymph nodes. These results indicate that it was inappropriate to predict the status of ER, PR and HER-2 in metastatic lymph nodes based on the results of evaluation of that in primary lesions.

Discordance rate of HER2 status in primary gastric carcinomas and synchronous lymph node metastases: a multicenter retrospective analysis

Background: The assessment of human epidermal growth factor receptor 2 (HER2) gene amplification is essential in order to identify those patients affected by advanced gastric cancer who may benefit from Trastuzumab targeted therapy. Materials and Methods: With the aim to investigate the concordance rate in HER2 status between primary gastric carcinoma (GC) and synchronous lymphnode metastases, we investigated HER2 status in a cohort of 108 surgical formalin-fixed paraffin-embedded specimens of GC and matched synchronous metastatic lymph nodes collected from three different units of Anatomic Pathology in southern of Italy. Fleiss-Cohen weighted k statistics were used to assess the concordance rate of HER2 status. Results: HER2 amplification was observed in 17% of primary GCs and the overall concordance rate with corresponding nodal metastases was 90.74%. Changes in HER2 status between primary GC and matched synchronous metastases were evidenced in 10 (9.26%) cases. Of these, 6 cases were HER2 amplified in the primary GC and not amplified in the metastases, while 4 were HER2 not amplified in the primary tumour and amplified in the lymph node metastases. Conclusions: Although at present the simultaneous determination of HER2 in advanced gastric cancer and corresponding metastatic lymph nodes is not mandatory, the possibility that the synchronous metastases of GC have a different HER2 status from that of the primary tumour is of remarkable significance; Indeed this may have influence on the therapeutic management and prognosis of the patients.

St Gallen molecular subtypes in primary breast cancer and matched lymph node metastases--aspects on distribution and prognosis for patients with luminal A tumours: results from a prospective randomised trial

Background

The St Gallen surrogate molecular subtype definitions classify the oestrogen (ER) positive breast cancer into the luminal A and luminal B subtypes according to proliferation rate and/or expression of human epidermal growth factor receptor 2 (HER2) with differences in prognosis and chemo-responsiveness. Primary tumours and lymph node metastases might represent different malignant clones, but in the clinical setting only the biomarker profile of the primary tumour is used for selection of adjuvant systemic treatment. The present study aimed to classify primary breast tumours and matched lymph node metastases into luminal A, luminal B, HER2-positive and triple-negative subtypes and compare the distributions.

Methods

Eighty-five patients with available tumour tissue from both locations were classified. The distribution of molecular subtypes in primary tumours and corresponding lymph node metastases were compared, and related to 5-year distant disease-free survival (DDFS).

Results

The St Gallen molecular subtypes were discordant between primary tumours and matched lymph node metastases in 11% of the patients (p = 0.06). The luminal A subtype in the primary tumour shifted to a subtype with a worse prognostic profile in the lymph node metastases in 7 of 45 cases (16%) whereas no shift in the opposite direction was observed (0/38) (p = 0.02). All subtypes had an increased hazard for developing distant metastasis during the first 5 years after diagnosis in both primary breast tumours and matched lymph node metastases, compared with the luminal A subtype.

Conclusion

The classification according to the St Gallen molecular subtypes in primary tumours and matched lymph node metastases, implicates a shift to a more aggressive subtype in synchronous lymph node metastases compared to the primary breast tumour. The selection of systemic adjuvant therapy might benefit from taking the molecular subtypes in the metastatic node into account.

Assessing the in vivo targeting efficiency of multifunctional nanoconstructs bearing antibody-derived ligands

A great challenge in nanodiagnostics is the identification of new strategies aimed to optimize the detection of primary breast cancer and metastases by the employment of target-specific nanodevices. At present, controversial proof has been provided on the actual importance of surface functionalization of nanoparticles to improve their in vivo localization at the tumor. In the present paper, we have designed and developed a set of multifunctional nanoprobes, modified with three different variants of a model antibody, that is, the humanized monocolonal antibody trastuzumab (TZ), able to selectively target the HER2 receptor in breast cancer cells. Assuming that nanoparticle accumulation in target cells is strictly related to their physicochemical properties, we performed a comparative study of internalization, trafficking, and metabolism in MCF7 cells of multifunctional nanoparticles (MNP) functionalized with TZ or with alternative lower molecular weight variants of the monoclonal antibody, such as the half-chain (HC) and scFv fragments (scFv). Hence, to estimate to what extent the structure of the surface bioligand affects the targeting efficiency of the nanoconjugate, three cognate nanoconstructs were designed, in which only the antibody form was differentiated while the nanoparticle core was maintained unvaried, consisting of an iron oxide spherical nanocrystal coated with an amphiphilic polymer shell. In vitro, in vivo, and ex vivo analyses of the targeting efficiency and of the intracellular fate of MNP-TZ, MNP-HC, and MNP-scFv suggested that the highly stable MNP-HC is the best candidate for application in breast cancer detection. Our results provided evidence that, in this case, active targeting plays an important role in determining the biological activity of the nanoconstruct.

Biomarker expression and St Gallen molecular subtype classification in primary tumours, synchronous lymph node metastases and asynchronous relapses in primary breast cancer patients with 10 years' follow-up

Molecular profiles of asynchronous breast cancer metastases are of clinical relevance to individual patients' treatment, whereas the role of profiles in synchronous lymph node metastases is not defined. The present study aimed to assess individual biomarkers and molecular subtypes according to the St Gallen classification in primary breast tumours, synchronous lymph node metastases and asynchronous relapses and relate the results to 10-year breast cancer mortality (BCM). Tissue microarrays were constructed from archived tissue blocks of primary tumours (N = 524), synchronous lymph node metastases (N = 147) and asynchronous relapses (N = 36). The samples were evaluated by two independent pathologists according to oestrogen receptor (ER), progesterone receptor (PR), Ki67 and human epidermal growth factor receptor 2 (HER2) by immunohistochemistry and in situ hybridisation. The expression of biomarkers and molecular subtypes in the primary tumour was compared with that in the synchronous lymph node metastases and relapses, and related to 10-year BCM. Discordances were found between primary tumours and relapses (ER: p = 0.006, PR: p = 0.04, Ki67: p = 0.02, HER2: p = 0.02, St Gallen subtypes: p = 0.07) but not between primary tumours and metastatic lymph node. Prognostic information was gained by the molecular subtype classification in primary tumours and nodal metastases; triple negative subtype had the highest BCM compared with the luminal A subtype (primary tumours: HR 4.0; 95 % CI 2.0-8.2, p < 0.001, lymph node metastases: HR 3.5; 95 % CI 1.3-9.7, p = 0.02). When a shift in subtype inherence between primary tumour and metastatic lymph node was identified, the prognosis seemed to follow the subtype of the lymph node. Molecular profiles are not stable throughout tumour progression in breast cancer. Prognostic information for individual patients appears to be available from the analysis of biomarker expression in synchronous metastatic lymph nodes. The study supports biomarker analysis also in asynchronous relapses.

ER, PR, HER2, Ki-67 and CK5 in Early and Late Relapsing Breast Cancer-Reduced CK5 Expression in Metastases

Breast cancer can recur even decades after the primary therapy. Markers are needed to predict cancer progression and the risk of late recurrence. The estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor-2 (HER2), proliferation marker Ki-67, and cytokeratin CK5 were studied to find out whether their expression or occurrence in subgroups of breast cancers correlated with the time of recurrence. The expression of HER2, ER, PR, Ki-67, and CK5 was studied by IHC in 72 primary breast cancers and their corresponding recurrent/metastatic lesions. The patients were divided into three groups according to the time of the recurrence/metastasis: before two years, after 5 years, and after 10 years. Based on their IHC profiles, the tumors were divided into surrogates of the genetically defined subgroups of breast cancers and the subtype definitions were as follows: luminal A (ER or PR+HER2–), luminal B (ER or PR+HER2+), HER2 overexpressing (ER–PR–HER2+), triple-negative (ER–PR–HER2–), basal-like (ER–PR–HER2–CK5+), non-classified (ER–PR–HER2–CK5–) and luminobasal (ER or PR+CK5+). In multivariate analysis, tumor size and HER2 positivity were a significant risk of early cancer relapse. The metastases showed a significantly lower CK5 expression. CK5 positivity distinguished triple negative tumors into rapidly and slowly recurring cancers. The IHC subtype ER or PR+HER2– luminal A presented a significantly lower risk of early tumor recurrence. Ki-67 expression denoted early-relapsing tumors and correlated linearly with tumor progression, since Ki-67 positivity declined gradually from early-relapsing toward late-recurring cancers.

Sample parameters affecting the clinical relevance of RNA biomarkers in translational breast cancer research

In the frame of translational breast cancer research, eligibility criteria for formalin-fixed paraffin-embedded tissue (FFPE) material processing for gene expression studies include tumor cell content (TCC) and sample site (primary vs metastatic tumors). Herein we asked whether the observed differences in gene expression between paired samples with respect to TCC and sample site also have different clinical significance. We assessed ESR1, ERBB2, MAPT, MMP7, and RACGAP1 mRNA expression with real time PCR in paired samples before (NMD) and after macrodissection (MD) from 98 primary tumors (P_MD, P_NMD) and 72 metastatic lymph nodes (LN_MD, LN_NMD), as well as from 93 matched P (mP) and LN (mLN). TCC range was 2.5–75 % in the NMD series and 28–98 % in the MD and in the mP/mLN series. The prognostic effect of these markers, individually or in clusters, remained stable between paired P_MD/NMD. In comparison, cluster classification failed in the LN_NMD group with lower TCC. In the mP/mLN cohort, RACGAP1 mRNA expression was of prognostic significance when tested in mLN samples (p < 0.001). Similarly, luminal B, HER2, and triple negative tumors were of dismal prognosis when classified in the LN component of the same series (mLN, overall survival: p = 0.013, p = 0.034, and p = 0.007, respectively). In conclusion, the clinical relevance of the RNA markers examined may be affected by TCC in metastatic LN samples but not in primary tumors, while it differs between primary tumors and matched metastases. These data will facilitate the design of translational studies involving FFPE sample series.

HER2 discordance between primary breast cancer and its paired metastasis: tumor biology or test artefact? Insights through meta-analysis

The proto-oncogene, HER2, has prognostic and predictive relevance in invasive breast cancer (IBC). HER2 testing of primary IBC guides treatment selection and is assumed to reflect HER2 status of associated metastases, although HER2 discordance between IBC and metastasis has been reported. Systematic review and meta-analysis of HER2 status in IBC and its paired loco-regional or distant metastasis were done. Quality appraisal considered whether (within-subject) testing conditions were maintained for paired primary and metastasis. Random effects logistic regression models were used to estimate pooled within-subject HER2 discordant proportions and to examine study-level covariates, including tumor-related and testing-related variables, potentially associated with HER2 discordance differences across (between) studies. Modelled paired HER2 data for primary and metastatic cancer (2520 subjects, 26 studies) showed a pooled HER2 discordance of 5.5% (3.6-8.5%). Sensitivity analysis, excluding the only study not maintaining same conditions for paired testing, gave a pooled estimate of 5.2% (3.5-7.8%). Pooled discordant proportion was not associated with differences between studies in test type, test scoring or interpretation criteria, subjects' median age, study time-frame, or HER2 positivity in primary cancer (all P > 0.05). However, type of metastasis was significantly associated with estimated HER2 discordance (P = 0.0017): studies of primary tumor paired with distant metastases had higher discordance [11.5% (6.9-18.6%)] than studies of primary paired with lymph node metastases only [4.1% (2.4-7.2%)], or those paired with nodal or various metastases [3.3% (2.0-5.6%)]; P < 0.01. HER2 discordant proportion was higher where paired metastases were metachronous relative to synchronous to primary IBC (P = 0.0024). Sensitivity analysis provided weak evidence (P = 0.074) that discordance in the direction of change from HER2-negative primary cancer to HER2-positive paired metastasis was more likely than the reverse. Study-level meta-analysis suggests factors associated with the type of metastasis as underlying mechanisms for observed HER2 discordance between primary IBC and paired metastasis. Test-related factors did not account for differences across studies in the HER2 discordant proportion.

Tracing the origins of metastasis

Cancer metastasis is often considered an orderly sequence of events leading to the colonization of distal organs by malignant cells. In fact, the evolution of metastatic disease is a dynamic process that is influenced by unique cellular lineages, altered microenvironments, distinct anatomical restrictions and multiple genetic and epigenetic alterations. These factors all contribute to variable clinical courses, likely requiring tailored therapy. As we inch closer towards personalized medicine, there is a renewed conceptual and technological focus on characterizing the cellular and genetic heterogeneity within tumours, to ultimately trace the origins of metastatic cells in different cancers.