Alterations in hormonal receptor expression and HER2 status between primary breast tumors and paired nodal metastases: discordance rates and prognosis

Biomarker conversion from primary breast cancer to synchronous axillary lymph node metastasis and neoadjuvant therapy response: a single-center analysis

PURPOSE

The biomarker characteristics of breast cancer plays an important role in predicting treatment sensitivity. The aim of the present study was to compare immunohistochemical profiles (ER, PR, HER2, and Ki67) between the primary tumor and synchronous axillary lymph node metastasis and investigate the subsequent effects on neoadjuvant therapy response.

METHODS

A total of 358 patients with pathologically confirmed synchronous axillary lymph node metastasis at first diagnosis and treated by neoadjuvant therapy at Peking University First Hospital from January 1, 2013 to December 31, 2022 were included in this retrospective study. Clinicopathologic data, especially receptor status in primary and metastatic foci, was collected for each case.

RESULTS

Change of ER, PR, HER2, and Ki67 expression was observed in 5.9%, 8.7%, 12.6%, and 17.3% of patients, respectively. HR discordance was observed more frequently when the ER status (p = 0.023) or PR status (p = 0.010) of primary tumor was negative, while HER2 discordance seemed to be more frequent when the HER2 status of primary tumor was HER2-0 or HER2-low (p < 0.001). Patients with loss of HR-positivity (positive to negative) responded to neoadjuvant chemotherapy better compared to those with stable positive HR expression (50% vs. 11.1%, p = 0.0017). A significantly decrease in pCR rate was observed in patients with unstable HER2 status, but not in the HER2-0/HER2-low subgroup.

CONCLUSION

Receptor discordance between primary tumor and synchronous axillary LNM appears to already exist before any anti-tumor therapy. This instability has limited clinical impact on the choice of neoadjuvant therapy at current stage, but further investigation is warranted with the incremental application of endocrine drugs and ADCs in neoadjuvant therapy.

Clinical relevance of biomarker discordance between primary breast cancers and synchronous axillary lymph node metastases

Clinical decision-making for patients with breast cancer (BC) is still primarily based on biomarker characteristics of the primary tumor, together with the evaluation of synchronous axillary lymph node metastasis (LNM). In this study, we investigated the prevalence of discordance in the biomarkers and surrogate subtyping between the primary BC and the LNM, and whether subsequent changes would have altered clinical treatment recommendations. In this retrospective study, 94 patients treated for unifocal primary BC and synchronous LNM at Sahlgrenska UniversityHospital during 2018 were included. Estrogen (ER) and progesterone (PR) receptor, Ki67, and HER2 status were assessed in the primary tumor and LNM using immunohistochemistry. Discordances between the primary tumor and the LNM were analyzed for each individual biomarker and surrogate subtyping. The concordance between the primary tumor and the LNM for ER, PR, Ki67, and HER2 status was 98.9%, 89.4%, 72.3%, and 95.8%, respectively. Discordance in surrogate subtyping was found in 28.7% of the tumors and matched LNMs, the majority (81.5%) of which changed to a more favorable subtype in the LNM; most commonly from Luminal B to Luminal A (48.6%). No changes in surrogate subtyping were detected where ER or HER2 status changed from negativity in the BC to positivity in the LNM, thereby showing no additional value in performing immunohistochemistry on the LNM from a treatment decision-making perspective. However, large studies need to be performed that test both the primary BCs and synchronous LNMs for more accurate diagnostics.

Heterogeneity between Core Needle Biopsy and Synchronous Axillary Lymph Node Metastases in Early Breast Cancer Patients-A Comparison of HER2, Estrogen and Progesterone Receptor Expression Profiles during Primary Treatment Regime

Simple Summary

All initial therapeutic decisions in early breast cancer are commonly based on the intrinsic subtype consisting of estrogen (ER), progesterone (PR), the human epidermal growth factor 2 (HER2) receptors and the proliferation marker Ki67. However, breast cancer is a very heterogeneous disease, and receptor expression is reported to change during progression. Little is known about receptor changes at the primary site. In a German single center study, we retrospectively analyzed a mostly therapy naive cohort of 215 primary breast cancer patients with axillary synchronous lymph node metastases (LNM). We compared core needle biopsy tissue of the primary tumor (t-CNB) to axillary LNM and detected receptor discordance for all three receptors at the primary site.

Abstract

In breast cancer therapeutic decisions are based on the expression of estrogen (ER), progesterone (PR), the human epidermal growth factor 2 (HER2) receptors and the proliferation marker Ki67. However, only little is known concerning heterogeneity between the primary tumor and axillary lymph node metastases (LNM) in the primary site. We retrospectively analyzed receptor profiles of 215 early breast cancer patients with axillary synchronous LNM. Of our cohort, 69% were therapy naive and did not receive neoadjuvant treatment. Using immunohistochemistry, receptor status and Ki67 were compared between core needle biopsy of the tumor (t-CNB) and axillary LNM obtained during surgery. The discordance rates between t-CNB and axillary LNM were 12% for HER2, 6% for ER and 20% for PR. Receptor discordance appears to already occur at the primary site. Receptor losses might play a role concerning overtreatment concomitant with adverse drug effects, while receptor gains might be an option for additional targeted or endocrine therapy. Hence, not only receptor profiles of the tumor tissue but also of the synchronous axillary LNM should be considered in the choice of treatment.

The Case to Case Comparison of Hormone Receptors and HER2 Status between Primary Breast Cancer and Synchronous Axillary Lymph Node Metastasis

Background:

Nowadays, the adjuvant treatment for breast cancer patients chosen depends on immunohistochemical pattern of Estrogen receptor(ER), Progesterone receptor(PR) and HER2 status of primary breast tumor. Several retrospective studies showed significant discordance in receptor expression between primary and metastatic tumors. The objective of this research was to determine discordant rate of ER, PR and HER2 status between primary breast cancer and synchronous axillary lymph node metastasis of individual breast cancer patients in Thammasat University Hospital.

Methods:

A prospective observational study of all breast cancer patients who have axillary metastasis and underwent surgery at Thammasat Hospital between January 2011 to December 2015. Tumor staging, ER, PR, and HER2 status on primary breast tumor were recorded. Synchronous axillary lymph node metastasis was evaluated with immunohistochemistry for ER, PR, and HER2.

Results:

The ER-positive rate from primary tumor to synchronous axillary lymph node metastasis decreased from 74.7% to 71.7%; the HER2 overexpression rate was decreased from 26% to 24%. In contrast, PR positive rate were 71% in both primary tumor and synchronous axillary lymph node metastasis. In case to case comparison, discordance rate of ER, PR and HER2 status between primary breast cancer and synchronous axillary lymph node metastasis were 11.1%, 20.2% and 10.1%, respectively. Furthermore, the tumor staging was not significant associated with discordance of ER, PR and HER2.

Conclusion:

ER, PR and HER 2 biomarkers showed significant concordance between primary tumor and synchronous axillary lymph node metastasis. Hence, if we cannot assess the ER, PR and HER2 status in primary tumor, then synchronous axillary lymph node metastasis can be studied instead. However, the repeat of biomarker testing in node-positive breast cancer patients may be beneficial for tailored adjuvant therapy, especially for patients with negative hormone receptor and/or HER2 profile on primary tumor.

Genomic comparison of paired primary breast carcinomas and lymph node macrometastases using the Oncotype DX Breast Recurrence Score® test

PURPOSE

Adjuvant therapy decisions may in part be based on results of Oncotype DX Breast Recurrence Score^® (RS) testing of primary tumors. When necessary, lymph node metastases may be considered as a surrogate. Here we evaluate the concordance in gene expression between primary breast cancers and synchronous lymph node metastases, based on results from quantitative RT-PCR-based RS testing between matched primary tumors and synchronous nodal metastases.

METHODS

This retrospective, exploratory study included patients (≥ 18 years old) treated at our center (2005-2009) who had ER+ , HER2-negative invasive breast cancer and synchronous nodal metastases with available tumor blocks from both sites. Paired tissue blocks underwent RS testing, and RS and single-gene results for ER, PR, and HER2 were explored between paired samples.

RESULTS

A wide distribution of RS results in tumors and in synchronous nodal metastases were modestly correlated between 84 paired samples analyzed (Pearson correlation 0.69 [95% CI 0.55-0.78]). Overall concordance in RS group classification between samples was 63%. ER, PR, and HER2 by RT-PCR between the primary tumor and lymph node were also modestly correlated (Pearson correlation [95% CI] 0.64 [0.50-0.75], 0.64 [0.49-0.75], and 0.51 [0.33-0.65], respectively). Categorical concordance (positive or negative) was 100% for ER, 77% for PR, and 100% for HER2.

CONCLUSIONS

There is modest correlation in continuous gene expression, as measured by the RS and single-gene results for ER, PR, and HER2 between paired primary tumors and synchronous nodal metastases. RS testing for ER+ breast cancer should continue to be based on analysis of primary tumors.

Hormone receptor, human epidermal growth factor receptor-2, and Ki-67 status in primary breast cancer and corresponding recurrences or synchronous axillary lymph node metastases

The therapeutic strategy for breast cancer is determined by the surrogate subtype, which is defined by biomarkers, such as estrogen receptor (ER), progesterone receptor (PgR), human epidermal growth factor receptor-2 (HER2), and Ki-67. In previous reports, the rate of discordance in ER, PgR, and HER2 between primary breast cancer and recurrent lesions or synchronous axillary lymph node metastasis was 15-25, 25-40, and 5-25 or 7-50, 10-50, and 3-30%, respectively. Overall, hormone receptors tended to weaken during the metastatic process, while patterns of HER2 were not uniform. Regarding the Ki-67 labeling index, an increase in metastatic lesions compared with primary lesions was the dominant pattern, suggesting that aggressive subclones with high proliferative potential form metastases. The loss of expression of hormone receptor or an increase in the Ki-67 labeling index in metastasis seemed to be associated with a poor prognosis. However, most previous studies did not report the background characteristics of patients, or they included subjects with varied characteristics, including those on systemic therapy, and were based on relatively small populations; therefore, definitive conclusions could not be drawn. Future studies should explore how to select therapies according to the biomarkers in primary breast cancer and/or its metastasis.

Variability in HER2 expression between primary colorectal cancer and corresponding metastases

PURPOSE

This study aimed to investigate the HER2 status of primary colorectal cancer (CRC) and corresponding metastases, and determine the correlation between HER2 and clinicopathological characteristics.

METHODS

We collected the clinicopathological features of 98 CRC patients and 66 patients which were previously evaluated for the KRAS status. The tissue samples of primary CRC tumors (n = 98), noninvolved colorectal mucosa (n = 98), paired lymph nodes (n = 98, 69 patients had positive metastatic nodes), and liver metastases (n = 22) were evaluated using immunohistochemistry for HER2. The kappa test was used to evaluate the concordance rate of HER2 status. Survival analysis was established according to the Kaplan-Meier method.

RESULTS

HER2 overexpression was more common in primary tumors among the younger patients (P < 0.05). No survival significance was revealed in the HER2 status. The HER2-positive rate was 11.2% for the primary CRC tumors, 0% for the normal adjacent mucosa tissues, 10.1% for the matched positive lymph nodes, and 31.8% for the corresponding metastasis. Seven of sixty-nine cases (10.1%) exhibited biomarker discordance in nodal metastases compared with primary tumors (κ = 0.48, P < 0.05); 6 out of 22 cases (27.3%) exhibited biomarker discrepancy in liver metastases compared with primary tumors (κ = 0.32, P > 0.05). Compared with lymph nodes, HER2 overexpression in the primary tissue was more common in KRAS wild-type patients (P < 0.05).

CONCLUSIONS

The present study showed a high rate of discordance in matched pairs of primary tumors and metastases, suggesting that the accurate evaluation of HER2 status is essential before any therapeutic decision.

Discordance of the estrogen receptor and HER-2/neu in breast cancer from primary lesion to first and second metastatic site

BACKGROUND

Hormone receptor and HER-2/neu discordance between the primary lesion and first metastasis has been reported. This study was performed to determine further biomarker discordance rates between the first and subsequent metastatic breast cancer lesions.

METHODS

We performed a retrospective review of paired biomarkers from primary breast cancers compared to first reported and subsequent metastases from 103 patients with breast cancer. The estrogen receptor (ER), progesterone receptor (PR), and HER-2/neu status were reported at all three time points. In addition, hormone, cytotoxic, and targeted treatments were recorded for primary and metastatic disease, and survival was determined.

RESULTS

Between the primary and first metastases, discordance rates for ER, PR, and HER-2/neu were 15.8%, 33.7%, and 14.3%, respectively. There was discordance between the first and second metastases for the ER receptor in 18.8%, PR receptor in 19.8%, and HER-2/neu in 10.7%. Overall, there was discordance between the primary tumor and either the first or second metastases for ER in 27.7%, PR receptor in 40.7%, and HER-2/neu in 19.6% of cases. Discordance of either ER or PR affected survival, with worse survival experienced by those patients with all three hormone receptors remaining negative, and intermediate survival reported for those with discordant tumors (ER χ2=14.27, p=0.0008; PR χ2=11.31, p=0.0035). There was no difference in survival for patients whose HER-2/neu tumors were discordant.

CONCLUSION

This study demonstrated that continued metastatic disease evolution may be associated with different tumor biology and that studies of metastatic lesions appear warranted, especially if targeted therapy is an option.

P-cadherin: a useful biomarker for axillary-based breast cancer decisions in the clinical practice

Axillary lymph node metastases represent the most powerful breast cancer prognostic factor, dictating disease staging and clinical therapeutic decisions. Nonetheless, breast cancer patients with positive lymph nodes still exhibit a heterogeneous behavior regarding disease progression. Stem-like subpopulations of cancer cells show high migratory and metastatic capacity, thus we hypothesize that breast cancer stem cell markers evaluation in metastasized lymph nodes could provide a more accurate prediction of patient's prognosis. Therefore, the expression profile of P-cadherin, CD44, and CD49f, which have been already associated to stem cell properties in breast cancer, has been evaluated by immunohistochemistry in a series of 135 primary tumors and matched axillary lymph node metastases from 135 breast cancer patients. Taking in consideration the expression of the stem cell markers only in axillary nodes, P-cadherin was the only biomarker significantly associated with poor disease-free and overall patient's survival. Moreover, although a concordant expression between primary tumors and matched lymph nodes has been found in the majority of the cases, a small but significant percentage displayed divergent expression (18.2-26.2%). Remarkably, although CD44 and CD49f changes between primary tumors and lymph node metastasis did not impact survival, the cases that were positive for P-cadherin in lymph node metastases being negative in the primary tumor, presented the worst disease-free and overall survival of the whole series. Accordingly, negative cases for this marker in the lymph nodes with positive expression in the matched breast carcinoma demonstrated a better prognosis, which overlapped with tumors that were negative in both sites. P-cadherin and CD49f gain of expression was mainly found in triple-negative carcinomas. Our results indicate for the first time that the evaluation of P-cadherin expression in lymph node metastases is an important predictor of disease outcome, being a putative valuable marker for axillary-based breast cancer decisions in the clinical practice.

A Comprehensive Model for Predicting Recurrence and Survival in Cases of Chinese Postoperative Invasive Breast Cancer

We investigated relationships between clinical pathologic data, molecular biomarkers and prognosis of invasive breast cancer based on a Chinese population. Immunohistochemistry (IHC) was used to assess the status of ER, PR, HER-2 and Ki-67, with fluorescence in situ hybridization (FISH) performed to further confirm HER-2 positivity with an equivocal result (IHC 2+). Subsequently, Kaplan-Meier univariate and multivariate COX regression analyses of ER, PR, HER-2, Ki-67, clinical features, therapeutic status and follow-up data were performed according to the establishment principle of the Nottingham prognostic index (NPI). From this study, age, tumor size, lymph node status, ER, HER-2, Ki-67 status were found to be associated with prognosis. Eventually, a prognostic model of (PI= (1.5×age) - size + (0.1×lymph node status) - (0.5×ER) + (2×HER-2) - (0.2×Ki-67)) was established with 288 randomly selected patients and verified with another 100 cases with invasive breast cancer. Pearson correlation analysis demonstrated a significant positive correlation index of 0.376 (P=0.012<0.05) between the prognostic index (PI) and actual prognosis. Remarkably, the consistency with the model predicted recurrence was 93% in the validation set. Therefore, it appears feasible to predict the prognosis of individuals with invasive breast cancer and to determine optimal therapeutic strategy with this model.

Could the Breast Prognostic Biomarker Status Change During Disease Progression? An Immunohistochemical Comparison between Primary Tumors and Synchronous Nodal Metastasis

BACKGROUND

Prognostic biomarkers in breast cancer are routinely investigated in the primary tumors to guide further management. However, it is proposed that the expression may change during the disease progression, and may result in a different immune profile in the metastatic nodes. This work aimed to investigate the expression of breast prognostic biomarkers in primary tumors and in its axillary nodal metastasis, to estimate the possible discordant expression.

MATERIALS AND METHODS

60 paired primary and axillary nodal metastasis samples were collected from patients with primary breast cancer with positive nodal deposits, diagnosed at the Maadi Military Hospital, Cairo, Egypt, during the year 2013. ER, PR and HER2 expression was assessed by immunohistochemistry in all samples

RESULTS

48.3% of the included cases showed concordant results for both ER and PR receptors between the primary tumor and its nodal metastasis while 51.7% showed discordant results and the discordance level was statistically significant. On the other hand, 70% of the cases showed concordant Her2 results between the primary tumors and the nodal deposits, 30% showed discordant results and the difference was significant.

CONCLUSIONS

The study indicated that the discordance in ER and PR receptor expression between the primary breast tumor and their nodal metastasis may be significant. The possible switch in the biomarker status during the disease progression is worth noting and may change the patient therapeutic planning. So, whether the treatment selection should be based on biomarkers in the lymph node is a topic for further studies and future clinical trials.