Concordance of immunohistochemistry for predictive and prognostic factors in breast cancer between biopsy and surgical excision: a single-centre experience and review of the literature

PURPOSE

Accurate evaluation of breast cancer on bioptic samples is of fundamental importance to guide therapeutic decisions, especially in the neoadjuvant or metastatic setting. We aimed to assess concordance for oestrogen receptor (ER), progesterone receptor (PR), c-erbB2/HER2 and Ki-67. We also reviewed the current literature to evaluate our results in the context of the data available at present.

METHODS

We included patients who underwent both biopsy and surgical resection for breast cancer at San Matteo Hospital, Pavia, Italy, between January 2014 and December 2020. ER, PR, c-erbB2, and Ki-67 immunohistochemistry concordance between biopsy and surgical specimen was evaluated. ER was further analysed to include the recently defined ER-low-positive in our analysis.

RESULTS

We evaluated 923 patients. Concordance between biopsy and surgical specimen for ER, ER-low-positive, PR, c-erbB2 and Ki-67 was, respectively, 97.83, 47.8, 94.26, 68 and 86.13%. Cohen's κ for interobserver agreement was very good for ER and good for PR, c-erbB2 and Ki-67. Concordance was especially low (37%) in the c-erbB2 1 + category.

CONCLUSION

Oestrogen and progesterone receptor status can be safely assessed on preoperative samples. The results of this study advise caution in interpreting biopsy results regarding ER-low-positive, c-erbB2/HER and Ki-67 results due to a still suboptimal concordance. The low concordance for c-erbB2 1 + cases underlines the importance of further training in this area, in the light of the future therapeutic perspectives.

Clinical significance and prognostic value of receptor conversion after neoadjuvant chemotherapy in breast cancer patients

The hormone receptor (HR) status and human epidermal growth hormone receptor 2 (HER2) status of patients with breast cancer may change following neoadjuvant chemotherapy (NAC). We retrospectively analyzed the clinical data of 294 patients with stage II/III breast cancer to evaluate the clinical significance and prognostic value of receptor transformation after NAC in breast cancer patients. Pathological complete response after NAC was achieved in 10.7% of patients. HR, estrogen receptor (ER), progesterone receptor (PR), HER2, and Ki-67 conversion rates were 9.2%, 6.5%, 13.0%, 4.4%, and 33.7%, respectively. Patients with stable HR (P = 0.01) and HER2 (P = 0.048) expression had more favorable overall survival (OS). Low or reduced Ki-67 expression was associated with better disease-free survival (DFS) (P < 0.001) and OS (P < 0.01). Multivariate analysis showed that the number of lymph nodes after NAC, HR conversion, and radiotherapy were independent prognostic factors for overall survival. HR conversion implied a higher risk of death [hazard ratio, 2.56 (95% confidence interval: 1.19-5.51); P = 0.016]. Patients with HR conversion after NAC who received endocrine therapy had better DFS (P = 0.674) and OS (P = 0.363) than those who did not receive endocrine therapy, even if the HR changed from positive to negative. In conclusion, pathological testing should be performed before and after NAC, and even patients with HR conversion after NAC might benefit from endocrine therapy.

Her2 Status Discrepancy Between Core Needle Biopsy and Surgically Resected Mastectomy Specimen: A Clinical Case

The biomarker concordance between core needle biopsy (CNB) and surgical specimen (SS), in breast cancer, has long been a matter of discussion because of its influence on oncologic treatment choice. Particularly, human epidermal growth factor receptor 2 (Her2) status is quite important, because of the impact on breast cancer classification and target therapy. Many factors could influence the difference in biomarker status between samples, such as the technic itself, sample procedures and intratumoral heterogeneity. Neoadjuvant chemotherapy (NAC) can also contribute to this variation and should be taken into consideration. We report a clinical case of a 33-year-old man who was diagnosed with right breast cancer, initially Her2 negative in the CNB. Therefore, the NAC was completed without anti-Her2 treatment. Later, after the mastectomy, revision of the SS was found to be positive for Her2, after the silver in situ hybridization (SISH) technique. Consequently, the patient lost the chance of doing anti-Her2 therapy in the neoadjuvant setting, reducing his possibility to achieve a complete pathologic response and later jeopardizing his clinical outcome.

Loss of HER2 in breast cancer: biological mechanisms and technical pitfalls

Loss of HER2 in previously HER2-positive breast tumors is not rare, occurring in up to 50% of breast cancers; however, clinical research and practice underestimate this issue. Many studies have reported the loss of HER2 after neoadjuvant therapy and at metastatic relapse and identified clinicopathological variables more frequently associated with this event. Nevertheless, the biological mechanisms underlying HER2 loss are still poorly understood. HER2 downregulation, intratumoral heterogeneity, clonal selection, and true subtype switch have been suggested as potential causes of HER2 loss, but translational studies specifically investigating the biology behind HER2 loss are virtually absent. On the other side, technical pitfalls may justify HER2 loss in some of these samples. The best treatment strategy for patients with HER2 loss is currently unknown. Considering the prevalence of this phenomenon and its apparent correlation with worse outcomes, we believe that correlative studies specifically addressing HER2 loss are warranted.

Concordance of breast cancer biomarker testing in core needle biopsy and surgical specimens: A single institution experience

BACKGROUND

Accurate diagnostic biomarker testing is crucial to treatment decisions in breast cancer. Biomarker testing is performed on core needle biopsies (CNB) and is often repeated in the surgical specimen (SS) after resection. As differences between CNB and SS testing may alter treatment decisions, we evaluated concordance between CNB and SS as well as associated changes in treatment and clinical outcomes.

METHODS

We performed a retrospective analysis of breast cancer patients at our institution between January 2010 and May 2020. Concordance between CNB and SS was assessed for estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) by immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH). Survival in patients, including recurrence, metastatic recurrence, and death, were assessed using chi-squared likelihood ratio.

RESULTS

In total, 961 patients met eligibility criteria. Concordance, minor discordance, total concordance (concordance plus minor discordance), and major discordance between CNB and SS were reported for ER (87.7%, 9.2%, 90.8%, and 2.9%), PR (58.1%, 29.1%, 87.2%, and 12.8%), and HER2 IHC (52.5%, 20.9%, 73.4%, 26.6%), respectively. HER2 FISH concordance and major discordance were 58.5% and 1.2%, respectively. Of major discordance, ER (48.2%, p < 0.001) and HER2 FISH (50.0%) led to more management changes than HER2 IHC (2.4%, p = 0.04) and PR (1.6%, p = 0.10). Patients with ER major discordance had increased risk of death (6.7% concordance vs. 22.2% major discordance, p = 0.004).

CONCLUSION

Overall, retesting ER and HER2 was more clinically beneficial than retesting PR. To aid decision-making and minimize healthcare costs, we propose patient-centered guidelines on retesting biomarker profiles.

Concordance between core needle biopsy and surgical excision for breast cancer tumor grade and biomarkers

PURPOSE

Histopathological biomarkers guide breast cancer management. Testing histopathological biomarkers on both core needle biopsy (CNB) and surgical excision (SE) in patients who are treated with upfront surgery is unnecessary and costly if there is high concordance between the two. This study investigated the concordance between CNB and SE for estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor-2 (HER2), tumor grade and Ki-67.

METHODS

Histopathological biomarker information were retrospectively collected from preoperative CNB and SE on patients diagnosed with breast cancer through the BreastScreen Sydney West program over a four-year period between January 2017 and December 2020. Data were then analyzed to calculate percentage of agreement and concordance using kappa values for ER, PR, HER2, tumor grade and Ki-67.

RESULTS

A total of 504 cases of invasive breast cancers were analyzed. There was substantial level of concordance for ER 96.7% (κ = 0.687) and PR 93.2% (κ = 0.69). Concordance for HER2 negative (IHC 0, IHC 1 +) or positive (IHC 3 +) tumor on CNB was 100% (κ = 1.00). Grade and Ki-67 showed moderate level of concordance, 72.6% (κ = 0.545) and 70.5% (κ = 0.453), respectively.

CONCLUSION

ER, PR and HER2 show high level of concordance. CNB is reliable in determining histopathological biomarkers for ER, PR positive and HER2 positive or negative tumors indicating that retesting these on SE may not be necessary.

High concordance of 70-gene recurrence risk signature and 80-gene molecular subtyping signature between core needle biopsy and surgical resection specimens in early-stage breast cancer

BACKGROUND AND OBJECTIVES

With increased neoadjuvant therapy recommendations for early-stage breast cancer patients due to the COVID-19 pandemic, it is imperative that molecular diagnostic assays provide reliable results from preoperative core needle biopsies (CNB). The study objective was to determine the concordance of MammaPrint and BluePrint results between matched CNB and surgical resection (SR) specimens.

METHODS

Matched tumor specimens (n = 121) were prospectively collected from women enrolled in the FLEX trial (NCT03053193). Concordance is reported using overall percentage agreement and Cohen's kappa coefficient. Correlation is reported using Pearson correlation coefficient.

RESULTS

We found good concordance for MammaPrint results between matched tumor samples (90.9%, κ = 0.817), and a very strong correlation of MammaPrint indices (r = 0.94). The concordance of BluePrint subtyping in matched samples was also excellent (98.3%).

CONCLUSIONS

CNB samples demonstrated high concordance with paired SR samples for MammaPrint risk classification and BluePrint molecular subtyping, suggesting that physicians are provided with accurate prognostic information that can be used to guide therapy decisions.

Real-world Evidence of Diagnostic Testing and Treatment Patterns in US Patients With Breast Cancer With Implications for Treatment Biomarkers From RNA Sequencing Data

OBJECTIVE/BACKGROUND

We performed a retrospective analysis of longitudinal real-world data (RWD) from patients with breast cancer to replicate results from clinical studies and demonstrate the feasibility of generating real-world evidence. We also assessed the value of transcriptome profiling as a complementary tool for determining molecular subtypes.

METHODS

De-identified, longitudinal data were analyzed after abstraction from records of patients with breast cancer in the United States (US) structured and stored in the Tempus database. Demographics, clinical characteristics, molecular subtype, treatment history, and survival outcomes were assessed according to strict qualitative criteria. RNA sequencing and clinical data were used to predict molecular subtypes and signaling pathway enrichment.

RESULTS

The clinical abstraction cohort (n = 4000) mirrored the demographics and clinical characteristics of patients with breast cancer in the US, indicating feasibility for RWE generation. Among patients who were human epidermal growth factor receptor 2-positive (HER2+), 74.2% received anti-HER2 therapy, with ∼70% starting within 3 months of a positive test result. Most non-treated patients were early stage. In this RWD set, 31.7% of patients with HER2+ immunohistochemistry (IHC) had discordant fluorescence in situ hybridization results recorded. Among patients with multiple HER2 IHC results at diagnosis, 18.6% exhibited intra-test discordance. Through development of a whole-transcriptome model to predict IHC receptor status in the molecular sequenced cohort (n = 400), molecular subtypes were resolved for all patients (n = 36) with equivocal HER2 statuses from abstracted test results. Receptor-related signaling pathways were differentially enriched between clinical molecular subtypes.

CONCLUSIONS

RWD in the Tempus database mirrors the overall population of patients with breast cancer in the US. These results suggest that real-time, RWD analyses are feasible in a large, highly heterogeneous database. Furthermore, molecular data may aid deficiencies and discrepancies observed from breast cancer RWD.

Is the 21-Gene Recurrence Score on Core Needle Biopsy Equivalent to Surgical Specimen in Early-Stage Breast Cancer? A Comparison of Gene Expression Between Paired Core Needle Biopsy and Surgical Specimens

BACKGROUND

Molecular testing on surgical specimens predicts disease recurrence and benefit of adjuvant chemotherapy in hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) early-stage breast cancer (EBC). Testing on core biopsies has become common practice despite limited evidence of concordance between core/surgical samples. In this study, we compared the gene expression of the 21 genes and the recurrence score (RS) between paired core/surgical specimens.

METHODS

Eighty patients with HR+/HER2- EBC were evaluated from two publicly available gene expression datasets (GSE73235, GSE76728) with paired core/surgical specimens without neoadjuvant systemic therapy. The expression of the 21 genes was compared in paired samples. A microarray-based RS was calculated and a value ≥ 26 was defined as high-RS. The concordance rate and kappa statistic were used to evaluate the agreement between the RS of paired samples.

RESULTS

Overall, there was no significant difference and a high correlation in the gene expression levels of the 21 genes between paired samples. However, CD68 and RPLP0 in GSE73235, AURKA, BAG1, and TFRC in GSE76728, and MYLBL2 and ACTB in both datasets exhibited weak to moderate correlation (r < 0.5). There was a high correlation of the microarray-based RS between paired samples in GSE76728 (r = 0.91, 95% confidence interval [CI] 0.81-0.96) and GSE73235 (r = 0.82, 95% CI 0.71-0.89). There were no changes in RS category in GSE76728, whereas 82% of patients remained in the same RS category in GSE73235 (κ = 0.64).

CONCLUSIONS

Gene expression levels of the 21-gene RS showed a high correlation between paired specimens. Potential sampling and biological variability on a set of genes need to be considered to better estimate the RS from core needle biopsy.

Association between Imaging Features using the BI-RADS and Tumor Subtype in Patients with Invasive Breast Cancer

BACKGROUND

Different molecular breast cancer subtypes present different biologic features, treatment options, and clinical prognoses. The breast cancer imaging phenotype may help precisely classify breast cancer in a non-invasive manner.

OBJECTIVE

To identify the association between the imaging and clinicopathologic features of invasive breast cancer according to the molecular subtype.

METHODS

We retrospectively reviewed the electronic medical records of 313 consecutive women with breast cancer who underwent surgery between March 2018 and February 2019. Preoperative imaging studies were also reviewed and the association between the clinicopathologic and imaging features was evaluated according to the molecular subtype.

RESULTS

On mammography, the presence of microcalcifications was correlated with the human epidermal factor receptor 2-positive subtype (67%, 14/21). Luminal A and B tumors were more likely to have a spiculated margin (57% [63/110] and 41% [34/81]), while human epidermal factor receptor 2-positive and triple-negative breast cancers were more likely to have an indistinct margin (56% [10/18] and 35% [17/48]). On ultrasonography, luminal A tumors were likely to be depicted as masses with an irregular shape (85%, 115/136) and spiculated margin (49%, 66/136). On magnetic resonance imaging, triple-negative breast cancer appeared as a mass (n=13) that frequently had an irregular shape (62%, 8/13) but was more likely to be oval or round (39%, 5/13) than other subtypes.

CONCLUSION

Some imaging features on mammography, ultrasonography, and magnetic resonance imaging could be useful predictors of the molecular subtype of breast cancer and may aid precision medicine development for patients with breast cancer according to the subtype.

Does Specimen Type Have an Impact on HER2 Status in Endometrial Serous Carcinoma? Discordant HER2 Status of Paired Endometrial Biopsy and Hysterectomy Specimens in the Presence of Frequent Intratumoral Heterogeneity

A recent clinical trial showed prolonged progression-free survival in human epidermal growth factor receptor 2 (HER2)-positive advanced stage and recurrent endometrial serous carcinomas when trastuzumab was added to traditional chemotherapy. Approximately one third of these tumors are HER2-positive and have been described to show unique characteristics of HER2 protein expression and gene amplification, including significant intratumoral heterogeneity, in recent studies. However, currently, there are no standard protocols for the selection of optimal specimen type or algorithm for HER2 testing in endometrial serous carcinomas. The current study aimed to evaluate the concordance of HER2 status between endometrial biopsy/curettage and subsequent hysterectomy specimens in endometrial serous carcinoma. A total of 57 patients with endometrial serous carcinoma with available HER2 status were identified during the study period, 14 of which (14/57, 25%) were HER2-positive by immunohistochemistry and/or fluorescent in situ hybridization (FISH). The final study cohort consisted of 40 paired endometrial biopsies/curettings and hysterectomies to include all 14 HER2-positive tumors and 26 selected HER2-negative tumors to represent an equal distribution of HER2 immunohistochemical scores. HER2 FISH was performed on all tumors with an immunohistochemical score of 2+. HER2 immunohistochemical scores, heterogeneity of HER2 expression, FISH results, and the overall HER2 status were compared between the 2 specimen types. HER2 status was successfully assigned in both specimen types in 37 cases, as three specimens showed inadequate FISH signals. Concordant HER2 status was observed in 84% of cases (31/37), with identical HER2 immunohistochemical scores in 65% (26/40) of tumors. Among the 6 tumors with a discordant HER2 status, 2 were HER2 negative in the biopsy and positive in the hysterectomy, and 4 were HER2-positive in the biopsy and negative in the hysterectomy. The false-negative rate would be 15.4% and 26.7% if only the biopsy or only the hysterectomy would be the basis for the result, respectively. Intratumoral heterogeneity of HER2 protein expression was present in 22 tumors (55%), including all cases with a discordant HER2 status. The concordance rate of HER2 status between paired endometrial biopsies/curettings and hysterectomies of endometrial serous carcinoma is lower than the reported rates of breast cancer, and comparable to those of gastric carcinomas. Frequent heterogeneity of HER2 protein expression combined with the possibility of a spatially more heterogenous sampling of endometrial cavity in biopsies and curettings, and the potential differences in specimen handling/fixation between the 2 specimen types may explain our findings. HER2 testing of multiple specimens may help identify a greater proportion of patients eligible for targeted trastuzumab therapy and should be taken into account in future efforts of developing endometrial cancer-specific HER2 testing algorithm.

Comparison of breast cancer surrogate subtyping using a closed-system RT-qPCR breast cancer assay and immunohistochemistry on 100 core needle biopsies with matching surgical specimens

Background

Routine clinical management of breast cancer (BC) currently depends on surrogate subtypes according to estrogen- (ER) and progesterone (PR) receptor, Ki-67, and HER2-status. However, there has been growing demand for reduced immunohistochemistry (IHC) turnaround times. The Xpert® Breast Cancer STRAT4* Assay (STRAT4)*, a standardized test for ESR1/PGR/MKi67/ERBB2 mRNA biomarker assessment, takes less than 2 hours. Here, we compared the concordance between the STRAT4 and IHC/SISH, thereby evaluating the effect of method choice on surrogate subtype assessment and adjuvant treatment decisions.

Methods

In total, 100 formalin-fixed paraffin-embedded core needle biopsy (CNB) samples and matching surgical specimens for 98 patients with primary invasive BC were evaluated using the STRAT4 assay. The concordance between STRAT4 and IHC was calculated for individual markers for the CNB and surgical specimens. In addition, we investigated whether changes in surrogate BC subtyping based on the STRAT4 results would change adjuvant treatment recommendations.

Results

The overall percent agreement (OPA) between STRAT4 and IHC/SISH ranged between 76 and 99% for the different biomarkers. Concordance for all four biomarkers in the surgical specimens and CNBs was only 66 and 57%, respectively. In total, 74% of surgical specimens were concordant for subtype, regardless of the method used. IHC- and STRAT4-based subtyping for the surgical specimen were shown to be discordant for 25/98 patients and 18/25 patients would theoretically have been recommended a different adjuvant treatment, primarily receiving more chemotherapy and trastuzumab.

Conclusions

A comparison of data from IHC/in situ hybridization and STRAT4 demonstrated that subsequent changes in surrogate subtyping for the surgical specimen may theoretically result in more adjuvant treatment given, primarily with chemotherapy and trastuzumab.

Variability in Breast Cancer Biomarker Assessment and the Effect on Oncological Treatment Decisions: A Nationwide 5-Year Population-Based Study

We compared estrogen receptor (ER), progesterone receptor (PR), human epidermal growth-factor receptor 2 (HER2), Ki67, and grade scores among the pathology departments in Sweden. We investigated how ER and HER2 positivity rates affect the distribution of endocrine and HER2-targeted treatments among oncology departments. All breast cancer patients diagnosed between 2013 and 2018 in Sweden were identified in the National Quality Register for Breast Cancer. Cases with data on ER, PR, HER2, Ki67, grade, and treatment were selected (43,261 cases from 29 departments following the guidelines for biomarker testing). The ER positivity rates ranged from 84.2% to 97.6% with 6/29 labs out of the overall confidence intervals (CIs), while PR rates varied between 64.8% and 86.6% with 7/29 labs out of the CIs. HER2 positivity rates ranged from 9.4% to 16.3%, with 3/29 labs out of the overall CIs. Median Ki67 varied between 15% and 30%, where 19/29 labs showed significant intra-laboratory variability. The proportion of grade-II cases varied between 42.9% and 57.1%, and 13/29 labs were outside of the CI. Adjusting for patient characteristics, the proportion of endocrine and anti-HER2 treatments followed the rate of ER and HER2 positivity, illustrating the clinical effect of inter- and intra-laboratory variability. There was limited variability among departments in ER, PR, and HER2 testing. However, even a few outlier pathology labs affected endocrine and HER2-targeted treatment rates in a clinically relevant proportion, suggesting the need for improvement. High variability was found in grading and Ki67 assessment, illustrating the need for the adoption of new technologies in practice.

Concordance of the 21-gene assay between core needle biopsy and resection specimens in early breast cancer patients

BACKGROUND

Adjuvant therapy decisions may be partly based on the results of a multigene quantitative reverse transcription-polymerase chain reaction (RT-PCR)-based assay: the 21-gene recurrence score (RS) test of resection specimens. When necessary, core needle biopsy (CNB) may be considered as a surrogate. Here, we evaluated the concordance in gene expression according to results from RT-PCR-based RS testing between paired CNBs and resection specimens.

METHODS

CNBs and resection specimens from 50 breast cancer (BC) patients were tested to calculate RSs. First, we examined the concordance of the ER, PR and HER-2 status of tissue samples indicated by immunohistochemical (IHC) and RT-PCR analyses. Then, we compared the IHC findings of ER, PR, HER-2 and Ki-67 staining across paired samples. Ultimately, the RS and single-gene results for ER, PR, HER-2 and Ki-67 were explored between paired samples.

RESULTS

The concordance between IHC and RT-PCR was 100%, 80.0% and 100% for ER, PR and HER-2, respectively, in both resection specimens and CNBs. The concordance for IHC ER, PR, HER-2 and Ki-67 status was 100%, 94.0%, 52.0% and 82.0%, respectively, between paired samples. RS results from paired samples showed a strong correlation. The overall concordance in RS group classification between samples was 74%, 72% and 78% based on traditional cutoffs, TAILORx cutoffs and ASCO guidelines, respectively. ER, PR, HER-2 and Ki-67 were modestly- to- strongly correlated between paired samples according to the RT-PCR results.

CONCLUSION

A modest- to- strong correlation of ER, PR, HER-2 and Ki-67 gene expression and RS between CNBs and resection specimens was observed in the present study. The 21-gene RS test could be reliably performed on CNBs. ER, PR and HER-2 status showed remarkable concordance between the IHC and RT-PCR analyses. The concordance between paired samples was high for the IHC ER, PR and Ki-67 results and low for HER-2.

Impact of immunohistochemical profile changes following neoadjuvant therapy in the treatment of breast cancer

Introduction

Currently, the indication for neoadjuvant chemotherapy is increasing in the treatment of breast cancer. Variability in the expression of biomarkers following neoadjuvant treatment has been observed, which could be accompanied by changes in the adjuvant treatment.

Objectives

The primary objective was to evaluate the variability of biomarkers prior to and following neoadjuvant therapy. Secondary objectives were to determine which tumour subtype (as determined by immunohistochemical markers) most frequently achieved pathological complete response (pCR); whether the biomarker variation resulted in a change in immunophenotype and subsequently modification to the adjuvant treatment.

Materials and methods

A retrospective observational analysis was carried out on patients with a diagnosis of breast cancer who had neoadjuvant therapy prior to surgery in the Breast Care Service of the Buenos Aires British Hospital between January 2009 and June 2020.

Results

One hundred and seventy-two patients were included. The pCR rate was 28.5%. The tumour immunophenotype that achieved pCR most frequently was the hormone receptor negative /HER2+ group with a value of 85.2%. The analysis was carried out on the 123 patients with residual disease. The observed variability for oestrogen receptors (ER) was 8.9%, for progesterone receptors (PR), 29.9% and for HER2, 13.8%. These changes were statistically significant. There were changes to the tumour immunophenotype in 26 cases (21.1%) with modifications to the adjuvant treatment in nine of these (34.6%; 7.3% of all tumours with residual disease).

Conclusions

In this study, we observed statistically significant variability in the expression of ER, PR and HER2 prior to and following neoadjuvant treatment, which identified modifications in the tumour immunophenotype in 21.1%, and changes to the adjuvant treatment in 7.3% of all tumours with residual disease, justifying the re-assay of biomarkers in the surgical specimen.

Concomitant use of 18F-FDG PET-CT SUVmax is useful in the assessment of Ki67 labeling index in core-needle biopsy specimens of breast cancer

Background

Ki67 is a recognized proliferative and predictive marker in invasive breast cancer. However, results of Ki67 evaluation are affected by the method employed for sample fixation or biopsy, as well as by intratumor heterogeneity. Here, we aimed to compare the Ki67 labeling index (Ki67LI) between core-needle biopsy specimens (CNBSs) and surgically resected specimens (SRSs) of invasive breast cancer, and verify whether the discordance in Ki67LI can be reduced by analyzing the maximum standardized uptake value (SUVmax) obtained from pretreatment whole-body positron emission tomography/computed tomography (PET/CT) in combination with Ki67LI.

Methods

Tumor tissues were obtained from 118 patients with invasive breast cancer. Ki67LI was evaluated in CNBSs and SRSs by immunohistochemistry. First, we directly compared Ki67LI between CNBS and SRS, "allowing a tolerance margin of 5%." We divided the Ki67LI values into three groups (Low: 0≤ Ki67LI ≤10, Intermediate: 10< Ki67LI <30, and High: 30≤ Ki67LI) and the SUVmax into three groups (SUVmax ≤4, 4< SUVmax <8, and 8≤ SUVmax). We then verified the concordance rate between CNBS and SRS in each group in combination with the SUVmax obtained by PET/CT.

Results

The median Ki67LI was 17.8% (0.5-75.9%) and 17.0% (1.0-75.7%) in CNBS and SRS, respectively. The overall Ki67LI concordance rate between CNBS and SRS was 37.3% (44/118). The concordance was improved in the Low and High Ki67LI groups by applying SUVmax thresholds of 4 [82.6% (19/23), P=0.033 and 8 (92.3% (12/13), P=0.009], respectively.

Conclusions

Our results indicated that CNBS Ki67LI alone was not able to reflect SRS Ki67LI with sufficient accuracy. By dividing CNBS Ki67LI into three classes in combination with SUVmax, tumor proliferation could be predicted with higher accuracy in patients with invasive breast carcinoma.

Differential kynurenine pathway metabolism in highly metastatic aggressive breast cancer subtypes: beyond IDO1-induced immunosuppression

Background

Immunotherapy has recently been proposed as a promising treatment to stop breast cancer (BrCa) progression and metastasis. However, there has been limited success in the treatment of BrCa with immune checkpoint inhibitors. This implies that BrCa tumors have other mechanisms to escape immune surveillance. While the kynurenine pathway (KP) is known to be a key player mediating tumor immune evasion and while there are several studies on the roles of the KP in cancer, little is known about KP involvement in BrCa.

Methods

To understand how KP is regulated in BrCa, we examined the KP profile in BrCa cell lines and clinical samples (n = 1997) that represent major subtypes of BrCa (luminal, HER2-enriched, and triple-negative (TN)). We carried out qPCR, western blot/immunohistochemistry, and ultra-high pressure liquid chromatography on these samples to quantify the KP enzyme gene, protein, and activity, respectively.

Results

We revealed that the KP is highly dysregulated in the HER2-enriched and TN BrCa subtype. Gene, protein expression, and KP metabolomic profiling have shown that the downstream KP enzymes KMO and KYNU are highly upregulated in the HER2-enriched and TN BrCa subtypes, leading to increased production of the potent immunosuppressive metabolites anthranilic acid (AA) and 3-hydroxylanthranilic acid (3HAA).

Conclusions

Our findings suggest that KMO and KYNU inhibitors may represent new promising therapeutic targets for BrCa. We also showed that KP metabolite profiling can be used as an accurate biomarker for BrCa subtyping, as we successfully discriminated TN BrCa from other BrCa subtypes.

Surrogate Molecular Classification of Invasive Breast Carcinoma: A Comparison Between Core Needle Biopsy and Surgical Excision, With and Without Neoadjuvant Therapy

Surrogate molecular classification identifies different subtypes of invasive breast carcinoma on the basis of their immunohistochemical markers. The purpose of the study is to verify whether the immunohistochemical markers and surrogate molecular subtypes can be correctly assessed on the core needle biopsy (CNB) when compared with the corresponding surgical excision (SE), with or without neoadjuvant treatment (NAT). Cases with invasive carcinomas identified on both CNB and SE were retrospectively selected. With immunohistochemistry for estrogen receptors (ER), progesterone receptors (PgR), Ki67, human epidermal growth factor receptor 2 (Her2), and molecular analysis for Her2, surrogate molecular classification was determined in 4 and 5 groups, according to the 2013 St Gallen consensus. A total of 1067 cases was considered and complete data for surrogate molecular classification were available for 988 cases (655 without NAT, 333 with NAT). Without NAT, concordance was strong for ER and Her2, moderate for PgR, and weak for Ki67; concordance for surrogate molecular classification was moderate. After NAT, lower concordance rates were recorded, with significant reduction of PgR (P<0.001) and Ki67 (P<0.001). Without NAT, the surrogate molecular subtypes of breast carcinoma can be reliably assessed on CNB; Ki67 and/or PgR may be repeated on SE when values are close to cutoffs to avoid tumor subtype misclassification. After NAT, it seems advisable to repeat at least Ki67 and PgR.

Estrogen, progesterone, and human epidermal growth factor receptor 2 discordance between primary and metastatic breast cancer

Background

The estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) statuses are frequently discordant between the primary tumor and metastatic lesions in metastatic breast cancer. This can have important therapeutic implications.

Patients and methods

In all, 541 patients with available receptor statuses from both primary tumor and metastatic lesion treated at Heidelberg and Tuebingen University Hospitals between 1982 and 2018 were included.

Results

Statistically significant discordance rates of 14% and 32% were found for ER and PR. HER2 status was statistically insignificantly discordant in 15% of patients. Gain in HER2 positivity was associated with an improved overall survival, whereas loss of HR positivity was associated with worse overall survival. Antiendocrine treatment differed in 20% of cases before and after biopsy and HER2-directed treatment in 14% of cases.

Conclusions

Receptor statuses are discordant between primary tumor and metastasis in a considerable fraction of patients with metastatic breast cancer. Next to a highly presumed predictive value with respect to efficacy of endocrine and HER2-targeted therapy, discordance seems to provide prognostically relevant information. Where feasible, metastatic lesions should be biopsied in accordance with current guidelines.

Electronic supplementary material

The online version of this article (10.1007/s10549-020-05746-8) contains supplementary material, which is available to authorized users.

A Prospective Study on Level of Concordance Between Core Needle Biopsy and Surgical Specimen for Assessing Oestrogen Receptor, Progesterone Receptor, and Her2/Neu Receptor Status in Carcinoma Breast and Its Implications on Treatment Decisions

A prospective study on the level of concordance between core needle biopsy specimen (CNB) and surgical specimen (SS) assesses the oestrogen receptor (ER), progesterone receptor (PR) and Her2/Neu receptor status in Carcinoma breast and its implications on treatment decisions. Ninety consecutive treatment naive operable breast cancer patients treated between September 2015 and April 2017 were included in our prospective study. All patients underwent core needle biopsy prior to definitive surgery. Immunohistochemistry (IHC) studies for ER, PR, and Her2/Neu receptor assay were done in both the CNB specimen and SS. The concordances between CNB specimen and SS for ER, PR, and Her2/Neu receptor were 92%, 88%, and 78% respectively. In our study, overall discordance for ER, PR, and Her2/Neu status based on IHC tests on CNB specimen and its corresponding SS was 41% (37 out of total 90 patients), which was mostly for Her2/Neu (20 patients). Altogether, there was a change in treatment decision based on IHC test results of CNB specimen for 14 out of 37 discordant tests, translating to 15% of the overall study group. Four patients received adjuvant hormonal therapy, and 10 patients got adjuvant Traztuzumab added to their protocol. There is almost perfect to substantial concordance between CNB specimen and SS of IHC tests for ER and PR status. However, the concordance for Her2/Neu receptor is only moderate. Her2/Neu receptor assay by IHC is more sensitive in CNB specimen than in SS.

Impact of chemotherapy on the expression of claudins and cadherins in invasive breast cancer

The importance of the expression profile of claudins in the molecular classification of breast cancer (BC) is currently under investigation. Claudins, together with cadherins, serve an important role in the epithelial-mesenchymal transition and influence the chemosensitivity of cancer cells. Adjuvant chemotherapy is administered following surgical resection in selected cases of BC. Previous neoadjuvant chemotherapy may change the molecular profile of a tumour and subsequently also its chemosensitivity. In the current study, the expression of claudin-1, −3 and −4, E- and N-cadherin and the standard BC biomarkers [oestrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2) and marker of proliferation Ki-67 (Ki-67)] in formalin-fixed, paraffin-embedded sections from 62 patients with invasive BC was analysed using immunohistochemistry prior to and following neoadjuvant chemotherapy. The results revealed increased expression of claudin-1 (P=0.03) and decreased expression of claudin-3 (P=0.005), PR (P<0.001) and Ki-67 (P=0.01) following the neoadjuvant therapy. No significant changes in the expression of ER, claudin-4 or E- and N-cadherin were observed following therapy. Furthermore, an association between the expression of claudin-1 and the standard BC markers (P<0.05) was identified. A high expression of claudin-1 was more frequently observed in the triple-negative BC cohort than in the cohort with positive ER, PR and/or HER2 before (P=0.04) and after chemotherapy (P=0.02). The expression of N-cadherin was associated with the expression of ER, PR, HER2 and tumour grade (P<0.05). A positive association between the expression of claudin-3 and E-cadherin (P=0.005) was observed. No association was found between the expression of E- and N-cadherin. In conclusion, significant changes in the expression of claudin-1 and −3 but not in the expression of claudin-4, E- and N-cadherin were observed in samples taken from patients with BC following chemotherapy. These findings indicate that claudins-1 and −3 serve a role in the response of BC to chemotherapy.

Higher ER load is not associated with better outcome in stage 1-3 breast cancer: a descriptive overview of quantitative HR analysis in operable breast cancer

PURPOSE

In breast cancer, hormone receptor (HR) status is generally a qualitative measure; positive or negative. Quantitatively measured oestrogen and progesterone receptors (ER and PR) are frequently proposed prognostic and predictive markers, some guidelines even provide different treatment options for patients with strong versus weak expression.

AIM

To evaluate quantitative HR load assessed by immunohistochemistry as a prognostic and predictive measure in stage 1-3 breast cancer.

METHODS

We reviewed all the available literature on quantitatively measured HRs using immunohistochemistry.

RESULTS

All included studies (n = 19) comprised a cohort of 30,754 patients. Only 2 out of 17 studies found a clear correlation between higher quantitative ER and better disease outcome. Only one trial examined quantitative ER both as prognostic and predictive marker and found no association between ER% and survival. Ten studies examined quantitative PR load, only two of those found a significant correlation between higher PR load and better disease outcome. Two trials examined quantitative PR both as prognostic and predictive marker, neither found any association between PR% and disease outcome.

CONCLUSIONS

There is no clear evidence for using quantitatively assessed ER and PR as prognostic nor predictive marker in patients with stage 1-3 breast cancer. We recommend only using a qualitative HR status in future guidelines and treatment considerations.

Prognostic assessment of breast carcinoma submitted to neoadjuvant chemotherapy with pathological non-complete response

Background

Breast cancer with pathological non-complete response (non-pCR) after neoadjuvant chemotherapy (NAC) has a worse prognosis. Despite Neo-Bioscore has been validated as an independent prognostic model for breast cancer submitted to NAC, non-pCR carcinoma was not assessed in this setting.

Methods

This is a retrospective trial that included women with localized breast cancer who underwent NAC and had non-pCR carcinoma in surgical specimen between 01/01/2013 to 12/31/2015 with a three-year follow-up. Survival analysis was performed by Kaplan-Meier estimator and hazard ratio (HR) set by log-rank test for the primary and secondary endpoints, respectively Disease-Free Survival (DFS) and Overall Survival (OS). According to Neo-Bioscore, the proposed prognostic model named Clustered Neo-Bioscore was classified into low (0–3), low-intermediate (4–5), high-intermediate (6) and high (7) risk. The prognostic accuracy for recurrence risk was assessed by time-dependent receiver operating characteristic (time-ROC) methodology. Multivariate Cox regression assessed the menopausal status, histological grade, Ki-67, estrogen receptor, HER2, tumor subtype, pathological and clinical stages. Confidence interval at 95% (CI95%) and statistical significance at set 2-sided p-value less than 0.05 were adopted.

Results

Among the 310 women enrolled, 267 patients (86.2%) had non-pCR carcinoma presenting size T3/T4 (63.3%), node-positive axilla (74.9%), stage III (62.9%), Ki-67 ≥ 20% (71.9%) and non-luminal A (78.3%). Non-pCR carcinoma presented worse DFS-3y (HR = 3.88, CI95% = 1.18–11.95) but not OS-3y (HR = 2.73, CI95% = 0.66–11.40). Clustered Neo-Bioscore discerned the recurrence risk for non-pCR carcinoma: low (DFS-3y = 0.86; baseline), low-intermediate (DFS-3y = 0.70; HR = 2.61), high-intermediate (DFS-3y = 0.13, HR = 14.05), and high (DFS-3y = not achieved; HR = 22.19). The prognostic accuracy was similar between Clustered Neo-Bioscore and Neo-Bioscore (0.76 vs 0.78, p > 0.05). Triple-negative subtype (HR = 3.6, CI95% = 1.19–10.92) and pathological stages II (HR = 5.35, CI95% = 1.19–24.01) and III (HR = 6.56, CI95% = 1.29–33.32) were prognoses for low-intermediate risk, whereas pathological stage III (HR = 13.0, CI95% = 1.60–106.10) was prognosis for low risk.

Conclusions

Clustered Neo-Bioscore represents a novel prognostic model of non-pCR carcinoma undergoing NAC with a more simplified and appropriate score pattern in the assessment of prognostic factors.

Electronic supplementary material

The online version of this article (10.1186/s12885-019-5812-0) contains supplementary material, which is available to authorized users.

[Clinical challenges and implications of intratumor heterogeneity]

Tumors display a high, albeit variable, grade of intratumor heterogeneity, both from a clinical and a morphological viewpoint. Furthermore, recent methods of large-scale molecular analysis demonstrate to what extent tumors can also be heterogeneous from a molecular perspective. This is of paramount importance for patients as it has a great impact on the success of so-called precision therapies and explains the reason for a significant number of therapeutic failures in modern oncology. We present an up-to-date review of the latest findings in a group of tumors with a high social impact, commonly seen in the daily routine of the pathology laboratory.

Ultrasound-Guided Core Needle Biopsies of Breast Invasive Carcinoma: When One Core is Sufficient for Pathologic Diagnosis and Assessment of Hormone Receptor and HER2 Status

Ultrasound (US)-guided core needle biopsy is considered the gold standard procedure with regard to preoperative diagnosis of breast carcinomas. However, there is no clear standard for the number of cores considered to be sufficient for pathologic evaluation, including the expression of surface hormone markers and HER2 status. Images and pathologic slides demonstrating breast invasive carcinoma from a single institution were thus retrospectively reviewed over a 12 month period. The results indicated that one core is sufficient for the diagnosis of invasive carcinomas, along with a reliable assessment of hormone receptor and HER2 status in many cases. The option of applying additional cores is recommended for some cases.

Estrogen receptor variants in ER-positive basal-type breast cancers responding to therapy like ER-negative breast cancers

Immunohistochemically ER-positive HER2-negative (ER+HER2−) breast cancers are classified clinically as Luminal-type. We showed previously that molecular subtyping using the 80-gene signature (80-GS) reclassified a subset of ER+HER2− tumors to molecular Basal-type. We report here that molecular reclassification is associated with expression of dominant-negative ER variants and evaluate response to neoadjuvant therapy and outcome in the prospective neoadjuvant NBRST study (NCT01479101). The 80-GS reclassified 91 of 694 (13.1%) immunohistochemically Luminal-type tumors to molecular Basal-type. Importantly, all 91 discordant tumors were classified as high-risk, whereas only 66.9% of ER+/Luminal-type tumors were classified at high-risk for disease recurrence (i.e., Luminal B) (P < 0.001). ER variant mRNA (ER∆3, ER∆7, and ERα-36) analysis performed on 84 ER+/Basal tumors and 48 ER+/Luminal B control tumors revealed that total ER mRNA was significantly lower in ER+/Basal tumors. The relative expression of ER∆7/total ER was significantly higher in ER+/Basal tumors compared to ER+/Luminal B tumors (P < 0.001). ER+/Basal patients had similar pathological complete response (pCR) rates following neoadjuvant chemotherapy as ER−/Basal patients (34.3 vs. 37.6%), and much higher than ER+/Luminal A or B patients (2.3 and 5.8%, respectively). Furthermore, 3-year distant metastasis-free interval (DMFI) for ER+/Basal patients was 65.8%, significantly lower than 96.3 and 88.9% for ER+/Luminal A and B patients, respectively, (log-rank P < 0.001). Significantly lower total ER mRNA and increased relative ER∆7 dominant-negative variant expression provides a rationale why ER+/Basal breast cancers are molecularly ER-negative. Identification of this substantial subset of patients is clinically relevant because of the higher pCR rate to neoadjuvant chemotherapy and correlation with clinical outcome.

What is the added value of digital image analysis of HER2 immunohistochemistry in breast cancer in clinical practice? A study with multiple platforms

AIMS

We aimed to compare digital image analysis (DIA) of human epidermal growth factor receptor 2 (HER2) immunohistochemistry (IHC) in breast cancer by two platforms: (i) to validate DIA against standard diagnostics; and (ii) to evaluate the added value of DIA in clinical practice.

METHODS AND RESULTS

HER2 IHC and in-situ hybridisation (ISH) were performed on 152 consecutive invasive breast carcinomas. IHC scores were determined with DIA using two independent platforms. Manual scoring was performed by two independent observers. HER2 status was considered positive in 3+ and ISH-positive 2+ cases. HER2 status using DIA was compared to HER2 status with standard diagnostics (manual scoring with ISH in 2+ cases). Interplatform agreement of IHC scores was 'moderate' (linear weighted κ = 0.58), agreement between manual scoring and platform A was 'moderate' (κ = 0.60) and between manual scoring and platform B 'almost perfect' (κ = 0.85). Compared to manual scoring, DIA resulted in a reduction of 2+ cases from 17.1 to 1.3% with platform A and from 17.1 to 15.8% with platform B. However, compared to standard diagnostics, there were three false-negative cases with DIA using platform A [81.3% sensitivity, 100% specificity, 100% positive predictive value (PPV), 97.8% negative predictive value (NPV)]. Sensitivity, specificity, PPV and NPV were 100% with DIA using platform B.

CONCLUSIONS

DIA of HER2 IHC is a valid tool in determining HER2 status in breast carcinoma. Algorithms in different platforms can behave differently, and optimal calibration is essential. In clinical practice, DIA offers an objective alternative to manual scoring, but a reduction in 2+ cases could result in loss of sensitivity.

Hormone- and HER2-receptor assessment in 33,046 breast cancer patients: a nationwide comparison of positivity rates between pathology laboratories in the Netherlands

Purpose

Patient management of invasive breast cancer (IBC) is to a large extent based on hormone- and HER2-receptor assessment. High-quality, reliable receptor assessment is of key importance as false results may lead to under- or overtreatment of patients. Surveillance of case-mix adjusted positivity rates has been suggested as a tool to identify laboratories with insufficient testing assays, as this covers the whole process of receptor assessment and enables laboratories to benchmark their positivity rates against other laboratories. We studied laboratory-specific variation in hormone- and HER2 positivity rates of 33,046 breast cancer patients using real-life nationwide data.

Methods

All synoptic pathology reports of IBC resection-specimens, obtained between 2013 and 2016, were retrieved from the nationwide Dutch pathology registry (PALGA). Absolute and case-mix adjusted receptor positivity rates were compared to the mean national proportion and presented in funnel plots in separate analyses for estrogen (ER), progesterone (PR) and HER2. Case-mix adjustment was performed by multivariable logistic regression.

Results

33,794 IBC lesions from 33,046 patients of 39 pathology laboratories were included. After case-mix adjustment, mean positivity rates were 87.2% for ER (range 80.4–94.3), 71.3% for PR (62.5–77.5%), and 9.9% for HER2 (5.5–12.7%). Overall, 14 (35.9%), 17 (43.6%) and 11 (28.2%) laboratories showed positivity rates outside the 95% confidence interval for ER, PR and HER2, respectively.

Conclusion

This nationwide study shows that absolute variation in hormone- and HER2-receptor positivity rates between Dutch pathology laboratories is limited. Yet, the considerable number of outlying laboratories shows that there is still need for improvement. Continuous monitoring and benchmarking of positivity rates may help to realize this.

Re-testing of predictive biomarkers on surgical breast cancer specimens is clinically relevant

PURPOSE

The accuracy of predictive and prognostic biomarker assessment in breast cancer is paramount since these guide therapy decisions. The aim was to investigate the concordance of biomarkers and immunohistochemical (IHC)-based surrogate tumor subtypes between core needle biopsies (CNB) and consecutive paired breast cancer surgical resections.

METHODS

This retrospective study comprised two cohorts of patients with primary breast cancer diagnosed between 2016 and 2017: one treated with primary surgery (n = 526) and one with neoadjuvant chemotherapy (NAC) (n = 216). The agreement between preoperative CNB and paired tumor specimens regarding the assessment of biomarkers and surrogate tumor subtypes was evaluated in both cohorts.

RESULTS

In the primary surgery cohort, the concordance rates and kappa values for estrogen receptor (ER), progesterone receptor (PR) and Ki67 were 98.6% (κ = 0.917), 89.3% (κ = 0.725) and 78.8% (κ = 0.529), respectively. Importantly, human epidermal growth factor receptor 2 (HER2) IHC assessment showed only moderate agreement (κ = 0.462). HER2 status combining IHC and in situ hybridization was discordant in 3.6% of cases, potentially impacting on indications for HER2-targeted therapy. The concordance rate for IHC-based surrogate tumor subtypes was only 73.2-78.3%. Generally lower concordance rates for ER, PR and HER2 were observed in the NAC cohort. Here, HER2 status was discordant in 7.4%.

CONCLUSIONS

The agreement of HER2 and Ki67 between CNB and paired surgical specimen in primary breast cancer is insufficient. Limited agreement of surrogate tumor subtypes indicates a significant clinical value of biomarker re-testing on surgical specimens.

Core needle biopsy as an alternative to whole section in IHC4 score assessment for breast cancer prognostication

AIMS

IHC4 score, based on expression of four routine markers (oestrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2) and proliferation marker, Ki67), is a recently developed, cost-effective prognostic tool in breast cancer. Possibly, the score may be useful also in advanced diseases where only core needle biopsy (CNB) is available and neoadjuvant therapy. However, its studies on CNB are scant. This study examined whether IHC4 score assessment on CNB is comparable to that from whole section (WS).

METHODS

Immunohistochemical (IHC) analysis was performed for ER, PR, HER2 and Ki67 on 108 paired CNB and WS to evaluate IHC4 score (with follow-up range 1-230 months and 5 relapse/death). Concordance between the two was examined. Factors that affected the concordance were analysed. Additionally, IHC4 score was compared with Nottingham Prognostic Index (NPI).

RESULTS

There was moderate concordance between IHC4 score on CNB and WS (all cases: κ=0.699, p<0.001; ER+ cases: κ=0.595, p<0.001). Among the IHC4 components, concordance for HER2 was the poorest (κ=0.178, p<0.001 in all cases; ER+ cases: κ=0.082, p<0.097). Significant factors affecting concordance between CNB and WS included number of cores, total core length and percentage of tumour cells in cores (p≤0.030), indicating the importance of sufficient sampling. Interestingly, the concordance was also affected by patients' age (p=0.039). There was poor agreement between IHC4 score and NPI (κ≤0.160).

CONCLUSION

Our results suggested that IHC4 score can be used on adequately sampled CNB. Its poor agreement with NPI highlights the independence of the two factors.

Assessment of HER2 status in breast cancer biopsies is not affected by accelerated tissue processing

AIMS

To establish whether core needle biopsy (CNB) specimens processed with an accelerated processing method with short fixation time can be used to determine accurately the human epidermal growth factor receptor 2 (HER2) status of breast cancer.

METHODS AND RESULTS

A consecutive case-series from two high-volume breast clinics was created. We compared routine HER2 immunohistochemistry (IHC) assessment between accelerated processing CNB specimens and routinely processed postoperative excision specimens. Additional amplification-based testing was performed in cases with equivocal results. The formalin fixation time was less than 2 h and between 6 and 72 h, respectively. Fluorescence in-situ hybridisation and multiplex ligation-dependent probe amplification were used for amplification testing. One hundred and forty-four cases were included, 15 of which were HER2-positive on the routinely processed excision specimens. On the CNB specimens, 44 were equivocal on IHC and required an amplification-based test. Correlation between the CNB specimens and the corresponding excision specimens was high for final HER2 status, with an accuracy of 97% and a kappa of 0.85.

CONCLUSIONS

HER2 status can be determined reliably on CNB specimens with accelerated processing time using standard clinical testing methods. Using this accelerated technology the minimum 6 h of formalin fixation, which current guidelines consider necessary, can be decreased safely. This allows for a complete and expedited histology-based diagnosis of breast lesions in the setting of a one-stop-shop, same-day breast clinic.

Concordance of immunohistochemistry between core needle biopsy and surgical resection of breast cancer

Background/aim: The purpose of this study was to evaluate the concordance of immunohistochemical (IHC) parameters of breast lesions between the core needle biopsy (CNB) and the surgical resection specimen. Materials and methods: CNB and resection specimens of female patients were retrospectively analyzed. ER, PR, HER-2, and Ki-67 parameters were compared for each patient. A total of 284 cases were assessed. Forty-one and 48 cases were excluded from the HER-2 and Ki-67 examinations, respectively, because the CNBs did not allow for IHC. Results: Concordance rates were 93.3% for ER, 89.4% for PR, 90.1% for HER-2, and 80.9% for Ki-67.Conclusion: CNB is accurate for the evaluation of the surrogate molecular profile of invasive breast cancer despite the heterogeneity of tumors.

Comparison of Core Needle Biopsy and Surgical Specimens in Determining Intrinsic Biological Subtypes of Breast Cancer with Immunohistochemistry

PURPOSE

We evaluated the concordance between core needle biopsy (CNB) and surgical specimens on examining intrinsic biological subtypes and receptor status, and determined the accuracy of CNB as a basic diagnostic method.

METHODS

We analyzed breast cancer patients with paired CNB and surgical specimen samples during 2014. We used monoclonal antibodies for nuclear staining, and estrogen receptor (ER) and progesterone receptor (PR) status evaluation. A positive test was defined as staining greater than or equal to 1% of tumor cells. Human epidermal growth factor receptor 2 (HER2) was graded by immunohistochemistry and scored as 0 to 3+ according to the recommendations of the American Society of Clinical Oncology/College of American Pathologists. Ki-67 immunostaining was performed using the monoclonal antibody Ki-67, and the results were divided at 10% intervals. The cutoff value for high Ki-67 was defined as 20%. Concordance analysis of ER, PR, HER2, Ki-67, and five intrinsic biological subtypes was performed on CNB and surgical specimens. Statistical analysis for concordance was calculated using κ-tests.

RESULTS

We found very good agreement for ER and PR with a concordance of 96.7% for ER (κ=0.903), and 94.3% for PR (κ=0.870). HER2 and Ki-67 showed concordance rates of 84.8% (κ=0.684) and 83.5% (κ=0.647), respectively, which were interpreted as good agreement. Five subgroups analysis showed 85.8% agreement and κ-value of 0.786, also indicating good agreement.

CONCLUSION

CNB showed high diagnostic accuracy compared with surgical specimens, and good agreement for ER, PR, HER2, and Ki-67. Our findings reaffirmed the recommendation of CNB as an initial procedure for breast cancer diagnosis, and the assessment of receptor status and intrinsic biological subtypes to determine further treatment plans.

Sonographic Phenotypes of Molecular Subtypes of Invasive Ductal Cancer in Automated 3-D Breast Ultrasound

Our aim was to investigate whether Breast Imaging Reporting and Data System-Ultrasound (BI-RADS-US) lexicon descriptors can be used as imaging biomarkers to differentiate molecular subtypes (MS) of invasive ductal carcinoma (IDC) in automated breast ultrasound (ABUS). We included 125 IDCs diagnosed between 2010 and 2014 and imaged with ABUS at two institutes retrospectively. IDCs were classified as luminal A or B, HER2 enriched or triple negative based on reports of histopathologic analysis of surgical specimens. Two breast radiologists characterized all IDCs using the BI-RADS-US lexicon and specific ABUS features. Univariate and multivariate analyses were performed. A multinomial logistic regression model was built to predict the MSs from the imaging characteristics. BI-RADS-US descriptor margins and the retraction phenomenon are significantly associated with MSs (both p < 0.001) in both univariate and multivariate analysis. Posterior acoustic features and spiculation pattern severity were only significantly associated in univariate analysis (p < 0.001). Luminal A IDCs tend to have more prominent retraction patterns than luminal B IDCs. HER2-enriched and triple-negative IDCs present significantly less retraction than the luminal subtypes. The mean accuracy of MS prediction was 0.406. Overall, several BI-RADS-US descriptors and the coronal retraction phenomenon and spiculation pattern are associated with MSs, but prediction of MSs on ABUS is limited.

Comparison of Core Needle Biopsy and Excision Specimens for the Accurate Evaluation of Breast Cancer Molecular Markers: a Report of 1003 Cases

In this study, we compared the accuracy of marker evaluation in core needle biopsy (CNB) specimens versus excision specimens (ESs) from breast cancer patients. This retrospective study used data collected from the breast cancer database at the West China Hospital, China. Immunohistochemistry (IHC) results from CNB specimens and ESs were compared, using estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2), and Ki-67 as markers. Molecular subtyping and endocrine therapy usage correlations based on CNB samples and ESs were evaluated. The results obtained from CNB samples and ESs exhibited substantial agreement for the detection of ER (κ = 0.522), PR (κ = 0.441), and HER2 (κ = 0.451), and also influenced endocrine therapy usage. Fair and poor correlations were observed for Ki-67 staining and molecular subtyping (κ = 0.195), respectively. This disagreement might be attributable to a combination of heterogeneity and large tumor size. This study indicates that the discordance rate in molecular marker staining between CNB specimens and ESs is significant enough that results obtained with CNB specimens should be used cautiously or verified using ESs.

Impact of molecular subtypes classification concordance between preoperative core needle biopsy and surgical specimen on early breast cancer management: Single-institution experience and review of published literature

BACKGROUND

Core needle biopsy (CNB) plays a crucial role as diagnostic tool for breast cancer (BC). The characterization of biomarkers status before surgical treatment is crucial when primary systemic therapy is a therapeutic option. The aim of this analysis was to report concordance between preoperative CNB and surgical specimen (SS) in evaluating biomarkers and molecular subtypes.

METHODS

Data have been collected from a cohort of 101 patients affected by early BC treated at Careggi Florence University Hospital, between January 2014 and March 2015. The conformity between molecular subtype classification was tested using kappa (κ) test.

RESULTS

Mean age was 57.5 years (range 29-86). There was concordance between the estrogen receptor (ER) assessment on CNB and SS in 95 cases (94.1%). Concordance of the progesterone receptor (PgR) assessment was observed in 89 cases (88.1%). Concordance for detecting immunohistochemistry-assessed BC molecular subtypes was 87.1% (κ = 0.78). Concerning Ki-67 evaluation, we report a concordance rate of 88.1% (κ = 0.68). The evaluation of luminal A plus luminal B/HER negative subgroup showed a κ-value of 0.65.

CONCLUSIONS

CNB showed good accuracy in evaluating hormonal receptors status, HER2, and BC molecular subtypes. Evaluation of Ki67 status was less accurate than other biomarkers; therefore, we recommend that it should be detected both on CNB and SS samples, especially in hormonal positive HER2 negative tumors, in order to avoid a misclassification of tumor subtypes that could lead to an omission of potential effective systemic therapy.

Hormonal Modulation of Breast Cancer Gene Expression: Implications for Intrinsic Subtyping in Premenopausal Women

Clinics are increasingly adopting gene-expression profiling to diagnose breast cancer subtype, providing an intrinsic, molecular portrait of the tumor. For example, the PAM50-based Prosigna test quantifies expression of 50 key genes to classify breast cancer subtype, and this method of classification has been demonstrated to be superior over traditional immunohistochemical methods that detect proteins, to predict risk of disease recurrence. However, these tests were largely developed and validated using breast cancer samples from postmenopausal women. Thus, the accuracy of such tests has not been explored in the context of the hormonal fluctuations in estrogen and progesterone that occur during the menstrual cycle in premenopausal women. Concordance between traditional methods of subtyping and the new tests in premenopausal women is likely to depend on the stage of the menstrual cycle at which the tissue sample is taken and the relative effect of hormones on expression of genes versus proteins. The lack of knowledge around the effect of fluctuating estrogen and progesterone on gene expression in breast cancer patients raises serious concerns for intrinsic subtyping in premenopausal women, which comprise about 25% of breast cancer diagnoses. Further research on the impact of the menstrual cycle on intrinsic breast cancer profiling is required if premenopausal women are to benefit from the new technology of intrinsic subtyping.

A prospective comparison of ER, PR, Ki67 and gene expression in paired sequential core biopsies of primary, untreated breast cancer

BACKGROUND

Sequential biopsy of breast cancer is used to assess biomarker effects and drug efficacy. The preoperative "window of opportunity" setting is advantageous to test biomarker changes in response to therapeutic agents in previously untreated primary cancers. This study tested the consistency over time of paired, sequential biomarker measurements on primary, operable breast cancer in the absence of drug therapy.

METHODS

Immunohistochemistry was performed for ER, PR and Ki67 on paired preoperative/operative tumor samples taken from untreated patients within 2 weeks of each other. Microarray analysis on mRNA extracted from formalin fixed paraffin embedded cores was performed using Affymetrix based arrays on paired core biopsies analysed using Ingenuity Pathway Analysis (IPA) and Gene Set Analysis (GSA).

RESULTS

In 41 core/resection pairs, the recognised trend to lower ER, PR and Ki67 score on resected material was confirmed. Concordance for ER, PR and Ki67 without changing biomarker status (e.g. ER+ to ER-) was 90, 74 and 80 % respectively. However, in 23 paired core samples (diagnostic core v on table core), Ki67 using a cut off of 13.25 % was concordant in 22/23 (96 %) and differences in ER and PR immunohistochemistry by Allred or Quickscore between the pairs did not impact hormone receptor status. IPA and GSA demonstrated substantial gene expression changes between paired cores at the mRNA level, including reduced expression of ER pathway analysis on the second core, despite the absence of drug intervention.

CONCLUSIONS

Sequential core biopsies of primary breast cancer (but not core versus resection) was consistent and is appropriate to assess the effects of drug therapy in vivo on ER, PR and Ki67 using immunohistochemistry. Conversely, studies utilising mRNA expression may require non-treatment controls to distinguish therapeutic from biopsy differences.

Tumour sampling method can significantly influence gene expression profiles derived from neoadjuvant window studies

Patient-matched transcriptomic studies using tumour samples before and after treatment allow inter-patient heterogeneity to be controlled, but tend not to include an untreated comparison. Here, Illumina BeadArray technology was used to measure dynamic changes in gene expression from thirty-seven paired diagnostic core and surgically excised breast cancer biopsies obtained from women receiving no treatment prior to surgery, to determine the impact of sampling method and tumour heterogeneity. Despite a lack of treatment and perhaps surprisingly, consistent changes in gene expression were identified during the diagnosis-surgery interval (48 up, 2 down; Siggenes FDR 0.05) in a manner independent of both subtype and sampling-interval length. Instead, tumour sampling method was seen to directly impact gene expression, with similar effects additionally identified in six published breast cancer datasets. In contrast with previous findings, our data does not support the concept of a significant wounding or immune response following biopsy in the absence of treatment and instead implicates a hypoxic response following the surgical biopsy. Whilst sampling-related gene expression changes are evident in treated samples, they are secondary to those associated with response to treatment. Nonetheless, sampling method remains a potential confounding factor for neoadjuvant study design.

Estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 expression in breast cancer FNA cell blocks and paired histologic specimens: A large retrospective study

BACKGROUND

Molecular analysis represents an increasingly important component of the pathologic examination of tumor specimens. Notably, the characterization of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) expression in breast cancer specimens provides critical prognostic and predictive information. The objective of the current study was to compare the concordance of these markers as determined on fine-needle aspiration (FNA) cell blocks compared with tissue blocks prepared from surgical specimens.

METHODS

A total of 134 cases of breast carcinoma were identified from 2002 through 2014 with both FNA cell blocks (fixed in 10% formalin) and corresponding available tissue blocks and ER, PR, and HER2 were characterized in both specimens. Negative and positive concordances were determined for ER and PR in cell blocks compared with tissue blocks, and for HER2 immunohistochemistry on cell blocks and tissue blocks versus the corresponding reference method, fluorescence in situ hybridization (FISH).

RESULTS

Concordance for ER expression evaluated on a cell block compared with the corresponding tissue block was 96.2%. Concordance for PR expression was 77.5%. Overall agreement of HER2 FISH testing between cell blocks and tissue blocks was 96.7%. For both cell blocks and tissue blocks, HER2 expression by immunohistochemistry demonstrated ≥98% positive and negative concordance with the FISH reference method.

CONCLUSIONS

ER, PR, and HER2 determination on FNA-acquired cell block (fixed exclusively in 10% formalin) showed excellent agreement for ER and HER2 and moderate agreement for PR with the corresponding tissue block. These findings support the equivalency of ER and HER2 evaluation performed on FNA cell blocks compared with surgical tissue blocks. Cancer Cytopathol 2016;124:828-35. © 2016 American Cancer Society.

Quantification of HER2 heterogeneity in breast cancer-implications for identification of sub-dominant clones for personalised treatment

Breast cancer is a heterogeneous disease, at both an inter- and intra-tumoural level. Appreciating heterogeneity through the application of biomarkers and molecular signatures adds complexity to tumour taxonomy but is key to personalising diagnosis, treatment and prognosis. The extent to which heterogeneity exists, and its interpretation remains a challenge to pathologists. Using HER2 as an exemplar, we have developed a simple reproducible heterogeneity index. Cell-to-cell HER2 heterogeneity was extensive in a proportion of both reported 'amplified' and 'non-amplified' cases. The highest levels of heterogeneity objectively identified occurred in borderline categories and higher ratio non-amplified cases. A case with particularly striking heterogeneity was analysed further with an array of biomarkers in order to assign a molecular diagnosis. Broad biological complexity was evident. In essence, interpretation, depending on the area of tumour sampled, could have been one of three distinct phenotypes, each of which would infer different therapeutic interventions. Therefore, we recommend that heterogeneity is assessed and taken into account when determining treatment options.

Spindle cell carcinoma of the breast: a comprehensive analysis

BACKGROUND

Breast spindle cell malignancies are rare. No standard treatment exists.

METHODS

The Surveillance, Epidemiology, and End Results database was used to identify patients with breast spindle cell malignancies, 1992 to 2011. Descriptive statistical analysis and survival analysis were performed.

RESULTS

A total of 286 patients were identified (98.6% female). Approximately, 15% had estrogen receptor-positive tumors and 12.5% had progesterone receptor-positive tumors. Nearly 38% underwent partial mastectomy, whereas 55.5% underwent mastectomy. The frequency of partial mastectomy has increased in more recent years. One-third received radiation. Lymph node metastases were infrequent (9.3%) and distant metastases were uncommon (6.1%). Ten-year survival rates for patients with early-stage (I and II) disease were 83.9% after partial mastectomy, 86.7% after partial mastectomy plus radiation, and 71.6% after complete mastectomy. Three-year survival rates for patients with late-stage (III and IV) disease were low with 40.0% after complete mastectomy and 0% after complete mastectomy plus radiation.

CONCLUSIONS

This nationally representative analysis demonstrates that early-stage spindle cell carcinoma of the breast is adequately treated by partial mastectomy. Radiation may be considered for small, potentially early survival benefit. For late stage disease, complete mastectomy is appropriate; however, survival is poor, and radiation contributes no significant additional benefit.

Construction of tissue microarrays from core needle biopsies - a systematic literature review

In some clinical circumstances, core needle biopsy (CNB) may be the only source of material from cancer tissue for diagnostic use. The volume of tissue available in a CNB is low, and opportunities for research use can therefore be limited. The tissue microarray (TMA) principle, if applied to the use of CNBs, could facilitate research studies in circumstances where CNB specimens are available. However, various challenges are expected in applying such a technique in CNBs, which has limited their use in research. We therefore conducted a systematic review of the literature on this subject. A systematic search was carried out with CINAHL, EMBASE, the Cochrane library, and MEDLINE, to identify studies that have primarily developed methods for constructing TMAs from CNBs. Eight studies were found to meet the inclusion criteria; six of these employed the vertical rearrangement technique, and two used multiple layers of biopsy tissue. Representation of the CNB was significantly influenced by the quantity of tumour cells present in the original biopsy and the degree of heterogeneity of biomarker expression. This review shows that technologies have been developed to enable construction of TMAs from CNBs. However, challenges remain to improve amplification and representation.

Reliability of Prognostic and Predictive Factors Evaluated by Needle Core Biopsies of Large Breast Invasive Tumors

OBJECTIVES

Preoperative biopsy of breast cancer allows for prognostic/predictive marker assessment. However, large tumors, which are the main candidates for preoperative chemotherapy, are potentially more heterogeneous than smaller ones, which questions the reliability of histologic analyses of needle core biopsy (NCB) specimens compared with whole surgical specimens (WSS). We studied the histologic concordance between NCB specimens and WSS in tumors larger than 2 cm.

METHODS

Early pT2 or higher breast cancers diagnosed between 2008 and 2011 in our center, with no preoperative treatments, were retrospectively screened. We assessed the main prognostic and predictive validated parameters. Comparisons were performed using the κ test.

RESULTS

In total, 163 matched NCB specimens and WSS were analyzed. The correlation was excellent for ER and HER2 (κ = 0.94 and 0.91, respectively), moderate for PR (κ = 0.79) and histologic type (κ = 0.74), weak for Ki-67 (κ = 0.55), and minimal for SBR grade (κ = 0.29). Three of the 21 HER2-positive cases (14% of HER2-positive patients or 1.8% of all patients), by WSS analysis, were initially negative on NCB specimens even after chromogenic in situ hybridization.

CONCLUSIONS

NCB for large breast tumors allowed reliable determination of ER/PR expression. However, the SBR grade may be deeply underestimated, and false-negative evaluation of the HER2 status would have led to a detrimental lack of trastuzumab administration.

Impact of preoperative evaluation of tumour grade by core needle biopsy on clinical risk assessment and patient selection for adjuvant systemic treatment in breast cancer

BACKGROUND

Histological characteristics are important when making a decision on adjuvant systemic treatment in breast cancer. Preoperative assessments of core needle biopsy (CNB) specimens are becoming increasingly relevant as novel minimally invasive ablative techniques are introduced, because a surgical specimen is no longer obtained with these methods. The clinical impact of potential underestimation of tumour grade on preoperative CNB on clinical decision-making was evaluated.

METHODS

Histological tumour grade was reassessed on CNB and resection specimens from consecutive invasive ductal carcinomas diagnosed between 2010 and 2013. For each patient, the indication for systemic therapy was assessed, based on either CNB or surgical excision, in combination with clinical characteristics and imaging findings. The clinical impact of discordance between tumour grade on CNB versus the resection specimen was assessed.

RESULTS

The analysis included 213 invasive ductal carcinomas in 199 patients. Discordance in tumour grade between CNB and the resection specimen was observed in 64 (30.0 per cent) of 213 tumours (κ = 0.53, 95 per cent c.i. 0.43 to 0.63). A decision on adjuvant treatment based on CNB would have resulted in overtreatment in seven (3.5 per cent) and undertreatment in three (1.5 per cent) of 199 patients. In the undertreated patients, incorrect omission of adjuvant systemic treatment would have increased the predicted 10-year mortality rate by 2.6-5.2 per cent and 10-year recurrence rate by 8.2-15.3 per cent based on the online risk assessment tool Adjuvant!

CONCLUSION

The substantial discordance in tumour grading between CNB and resection specimens from breast cancer affects the indication for adjuvant therapy in only a small minority of patients with invasive ductal carcinoma. Assessment of tumour grade by CNB is feasible and accurate for the planning of postoperative treatment.