High inter-laboratory variability in the assessment of HER2-low breast cancer: a national registry study on 50,714 Danish patients

BACKGROUND

Considering the recent advancements in the treatment of breast cancer with low expression of human epidermal growth factor receptor 2 (HER2), we aimed to examine inter-laboratory variability in the assessment of HER2-low breast cancer across all Danish pathology departments.

METHODS

From the Danish Breast Cancer Group, we obtained data on all women diagnosed with primary invasive breast cancer in 2007-2019 who were subsequently assigned for curatively intended treatment.

RESULTS

Of 50,714 patients, HER2 score and status were recorded for 48,382, among whom 59.2% belonged to the HER2-low group (score 1+ or 2+ without gene amplification), 26.8% had a HER2 score of 0, and 14.0% were HER2 positive. The proportion of HER2-low cases ranged from 46.3 to 71.8% among pathology departments (P < 0.0001) and from 49.3 to 65.6% over the years (P < 0.0001). In comparison, HER2 positivity rates ranged from 11.8 to 17.2% among departments (P < 0.0001) and from 12.6 to 15.7% over the years (P = 0.005). In the eight departments with the highest number of patients, variability in HER2-low cases increased from 2011 to 2019, although the same immunohistochemical assay was used. By multivariable logistic regression, the examining department was significantly related to both HER2 score 0 and HER2 positivity (P < 0.0001) but showed greater dispersion in odds ratios in the former case (range 0.25-1.41 vs. 0.84-1.27).

CONCLUSIONS

Our data showed high inter-laboratory variability in the assessment of HER2-low breast cancer. The findings cast doubt on whether the current test method for HER2 is robust and reliable enough to select HER2-low patients for HER2-targeted treatment in daily clinical practice.

Should a borderline negative HER2 result in a core biopsy of invasive carcinoma of the breast have HER2 assessment repeated in the excision specimen?

AIM

The 2015 UK guidelines for HER2 assessment in breast cancer recommended repeat assessment if the core biopsy was scored as 2+ on HER2 immunohistochemistry (IHC) with borderline negative in situ hybridisation (ratio of number of HER2 to chromosome 17 centromere copies of 1.8-1.99). This case series aimed to assess the value of such repeat assessment in the surgical specimen, in particular the proportion that were HER2 positive.

METHODS

Details of biopsies with 2+ IHC and borderline negative in situ hybridisation were extracted from a database. The results of repeat HER2 testing in the surgical specimen for this cohort study were then obtained.

RESULTS

112 patients with no preoperative treatment had repeat assessment: 4 were 3+ and 16 were 2+ amplified. Of 14 with preoperative chemotherapy, 1 was 3+ and 4 were 2+ amplified. All the 2+ amplified carcinomas had a HER2 to chromosome 17 ratio less than 4, in 50% the ratio was between 2.0 and 2.2, and in 50% the HER2 copy number was less than 4.

CONCLUSIONS

Repeat assessment yielded 4% 3+ results and 14% 2+ amplified carcinomas but with low level amplification. These results suggest that retesting of borderline negative HER2 cases should be optional and no longer mandatory.

The accuracy of ultrasound-guided fine-needle aspiration and core needle biopsy in diagnosing axillary lymph nodes in women with breast cancer: a systematic review and meta-analysis

Background

This study evaluates the diagnostic accuracy of ultrasound-guided fine needle aspiration (US-FNA) and core needle biopsy (US-CNB) for detecting axillary lymph nodes in women with breast cancer.

Methods

Eligible studies and pertinent literature resources were identified in Cochrane, PubMed, Embase, CNKI, VIP, and Wanfang databases using subject-specific keywords. Study outcomes were tested for heterogeneity, and meta-analyses were performed to estimate sensitivity, specificity, and diagnostic odds ratios (DORs). The summary receiver operating characteristic (SROC) curve analysis was also performed.

Results

A total of 22 studies involving 3,548 patients were included to evaluate the diagnostic accuracy of US-FNA and 11 studies involving 758 patients were included to evaluate the diagnostic accuracy of US-CNB in identifying axillary lymph nodes in women with breast cancer. The accuracy of US-FNA in identifying suspicious axillary lymph nodes was as follows: overall sensitivity, 79% (95% CI: 73%-84%); global specificity, 96% (95% CI: 92%-98%); overall positive likelihood ratio, 18.55 (95% CI: 10.53-32.69); overall negative likelihood ratio, 0.22 (95% CI: 0.17-0.28); DOR, 71.68 (95% CI: 37.19-138.12); and the area under the SROC curve, 0.94 (95% CI: 0.92-0.96). The accuracy of US-CNB in identifying suspicious axillary lymph nodes was as follows: overall sensitivity, 85% (95% CI: 81%-89%); global specificity, 93% (95% CI: 87%-96%); overall positive likelihood ratio, 11.88 (95% CI: 6.56-21.50); overall negative likelihood ratio, 0.16 (95% CI: 0.12-0.21); overall DOR, 66.83 (95% CI: 33.28-134.21), and the area under SROC curve 0.96 (95% CI: 0.94-0.97).

Conclusions

The results indicate that both US-FNA and US-CNB have high accuracy for suspicious axillary lymph nodes.

The clinical value of progesterone receptor expression in luminal breast cancer: A study of a large cohort with long-term follow-up

BACKGROUND

The routine assessment of progesterone receptor (PR) expression in breast cancer (BC) remains controversial. This study aimed to evaluate the role of PR expression in luminal BC, with emphasis on the definition of positivity and its prognostic significance as compared to Ki67 expression.

METHODS

A large cohort (n = 1924) of estrogen receptor (ER)-positive/HER2-negative BC was included. PR was immunohistochemically (IHC) stained on full face sections and core needle biopsies (CNB) where the optimal scoring cutoff was evaluated. In addition, the association of PR with other clinicopathological factors, cellular proliferation, disease outcome, and response to adjuvant therapy were analyzed.

RESULTS

Although several cutoffs showed prognostic significance, the optimal cutoff to categorize PR expression into two clinically distinct prognostic groups on CNB was 10%. PR negativity showed a significant association with features of aggressive tumor behavior and poor outcome. Multivariate analyses indicated that the association between PR negativity and poor outcome was independent of tumor grade, size, node stage, and Ki67. PR negativity showed independent association with shorter survival in patients who received endocrine therapy whereas Ki67did not.

CONCLUSION

PR IHC expression provides independent prognostic value superior to Ki67. Routine assessment of PR expression in BC using 10% cutoff in the clinical setting is recommended.

PLAIN LANGUAGE SUMMARY

In this study, we have established an optimal approach to determine the prognostic value of progesterone receptor expression in estrogen receptor-positive breast cancer patients. To do this, the levels of progesterone receptor were measured in a large cohort of estrogen receptor-positive breast cancer patients. We have refined the definition of progesterone receptor positivity in estrogen receptor-positive breast cancer. We show that progesterone receptor expression adds prognostic and predictive value of endocrine therapy in estrogen receptor-positive breast cancer patients, and our results show that the absence of progesterone receptor is associated with poorer outcomes independent of tumor grade, size, node stage, and Ki67 expression.

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.

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.

Biomarker Discordances and Alterations Observed in Breast Cancer Treated with Neoadjuvant Chemotherapy: Causes, Frequencies, and Clinical Significances

PURPOSE

Biomarker discordances and alterations can be encountered between tru-cut biopsy and residual tumor in breast cancer treated with neoadjuvant chemotherapy (NACTx). We aimed to investigate the effect of NACTx on major biomarker expression (ER, PR, HER2, Ki-67) and tumor grade, the frequency and causes of receptor discordances, and the clinical significance of changes in terms of adjuvant therapy need and chemosensitivity.

METHODS

In this retrospective study, ER, PR, HER2, and Ki-67 expression and tumor grades were compared between pre- and post-NACTx tumor samples using the Wilcoxon signed-rank test. The frequencies of receptor discordances and the need for new adjuvant therapy due to discordances were calculated. The effect of patient and tumor characteristics and NACTx regimens on discordances was investigated using multivariate analysis. Using histopathological examinations, residual tumors were divided into chemotherapy-responsive and chemotherapy-unresponsive tumors. Biomarker changes in both groups were analyzed for predictability of chemosensitivity.

RESULTS

Of the 169 patients who received NACTx, 102 patients having enough residual tumors in the surgical pathology specimen were enrolled in the study. Histopathologically, about 70% of tumors were partially responsive to NACTx and 30% were unresponsive (chemo-resistant). The concordance and discordance rates were 95.1% versus 4.9% for ER (p = 0.180), 97.1% versus 2.9% for PR (p = 0.083), and 89.2% versus 10.8% for HER2 (p = 0.763), respectively. In addition, 15% of hormone receptor (HR)-negative patients became HR(+) and 5.7% of HER2(-) patients became HER2(+) in the residual tumors, requiring adjuvant endocrine or anti-HER2 therapy. In particular, 18% of triple-negative patients became HR(+) and 12% became HER2(+). HER2 loss was detected in 40% of HER2(+) patients. Multivariate logistic regression analysis revealed that lower estrogen expression (p = 0.046), a smaller tumor size (p = 0.029), and anti-HER2 therapy (p < 0.001) have independent efficacy on ER discordance, PR discordance, and HER2 discordance, respectively. Ki-67 and PR expression significantly decreased in chemotherapy-responsive tumors (p = 0.001 and p = 0.004), and the tumor grade increased in chemotherapy-unresponsive tumors (p = 0.034).

CONCLUSIONS

Approximately 3-5% of HR discordance and about 10% of HER2 discordance can be observed in breast cancer after currently used NACTx regimens. Discordances are bi-directional (from positive to negative and vice versa), and their causes are multifactorial; they should be assessed accordingly. The NACTx effect alone cannot explain observed discordances but can cause biomarker alterations. The change in receptor status from positive to negative, especially HER2 loss, is mainly associated with the NACTx effect. However, the shift from negative to positive is thought to be primarily related to intratumoral heterogeneity. Receptor statuses becoming positive are of more clinical importance due to adjuvant therapy requirements. Biomarker alterations in PR, Ki-67, and tumor grade can provide predictive information about tumor chemosensitivity.

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.

Receptor Status after Neoadjuvant Therapy of Breast Cancer: Significance and Implications

Neoadjuvant chemotherapy (NACT) is now established in routine management of early breast cancer. Alterations in oestrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) following NACT are reported, with wide variation in results across series. In larger series, changes in ER status are identified in 5-23%, whilst changes in PR status are more frequent (14.5-67%). HER2 status changes less frequently with loss being more common than gain, and higher rates of change with immunohistochemistry are observed compared to in situ hybridization and following HER2-targeted therapy compared with chemotherapy alone. Triple negative is the most stable molecular subtype with combined ER, and HER2-positive cancers show the highest rate of change. Neoadjuvant endocrine therapy is used less commonly than NACT, and whilst loss of ER is rare, changes in PR status can occur in up to 40% of cases. There is relatively little published data on the impact of change in receptor status on survival outcomes. In patients whose tumours become ER or HER2 positive post-NACT, endocrine or anti-HER2 therapy can be initiated, although evidence from clinical trials is lacking. Most guidelines do not currently recommend routine retesting; however it should be considered in some circumstances.

HER2-low-positive breast cancer: evolution from primary tumor to residual disease after neoadjuvant treatment

Approximately a half of breast tumors classified as HER2-negative exhibit HER2-low-positive expression. We recently described a high instability of HER2-low-positive expression from primary breast cancer (BC) to relapse. Previous studies reporting discordance in HER2 status between baseline biopsy and residual disease (RD) in patients undergoing neoadjuvant treatment did not include the HER2-low-positive category. The aim of this study is to track the evolution of HER2-low-positive expression from primary BC to RD after neoadjuvant treatment. Patients undergoing neoadjuvant treatment with available baseline tumor tissue and matched samples of RD (in case of no pCR) were included. HER2-negative cases were sub-classified as HER2-0 or HER2-low-positive (IHC 1+ or 2+ and ISH negative). Four-hundred forty-six patients were included. Primary BC phenotype was: HR-positive/HER2-negative 23.5%, triple-negative (TN) 35%, HER2-positive 41.5%. HER2-low-positive cases were 55.6% of the HER2-negative cohort and were significantly enriched in the HR-positive/HER2-negative vs. TN subgroup (68.6% vs. 46.8%, p = 0.001 χ2 test). In all, 35.3% of non-pCR patients (n = 291) had a HER2-low-positive expression on RD. The overall rate of HER2 expression discordance was 26.4%, mostly driven by HER2-negative cases converting either from (14.8%) or to (8.9%) HER2-low-positive phenotype. Among HR-positive/HER2-negative patients with HER2-low-positive expression on RD, 32.0% and 57.1% had an estimated high risk of relapse according to the residual proliferative cancer burden and CPS-EG score, respectively. In conclusion, HER2-low-positive expression showed high instability from primary BC to RD after neoadjuvant treatment. HER2-low-positive expression on RD may guide personalized adjuvant treatment for high-risk patients in the context of clinical trials with novel anti-HER2 antibody-drug conjugates.

Predictive value of ductal carcinoma in situ with invasive breast cancer in core needle biopsies for final pathologic size of intraductal elements

Preoperative evaluations of the size of ductal carcinoma in situ (DCIS) extension in invasive breast cancer (IBC) are problematic and markers of the actual size of DCIS remain elusive. This study aimed to quantify DCIS on core needle biopsy (CNB) and investigated its association with degree of DCIS extension on paired resection specimens, instead of with presence or absence of an extensive intraductal component or margin status as in earlier studies. This series examined 150 IBCs diagnosed from paired CNB and resection specimens. The DCIS/invasion ratio was calculated using the sum of each element size from CNB. In resection specimens, cases in which the greatest dimension of DCIS extension was longer than the greatest dimension of invasive size were defined as extended DCIS (Ext-DCIS). DCIS/invasion ratio level correlated positively with the degree of Ext-DCIS (P = 0.003). Using receiver operating characteristic curve analysis, setting cases with the subgroup of DCIS extension with greatest dimension > 2.5 times that of the invasive size in the resection specimen (Ext-DCIS > 2.5) as the positive class provided the best discrimination ability for DCIS/invasion ratio (0.375). In multivariate analysis, DCIS/invasion ratio > 0.375 was significantly associated with Ext-DCIS > 2.5 (P = 0.033). In conclusion, DCIS/invasion ratio > 0.375 in CNB was identified as a predictor of Ext-DCIS > 2.5 in resection specimens, suggesting that an approach combining DCIS/invasion ratio from CNB with preoperative staging may better predict the extent of DCIS and facilitate better surgical planning.

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.

[2021 update of the GEFPICS' recommendations for HER2 status assessment in invasive breast cancer in France]

The last international guidelines on HER2 determination in breast cancer have been updated in 2018 by the American Society of Clinical Oncology and College of American Pathologists, on the basis of a twenty-year practice and results of numerous clinical trials. Moreover, the emerging HER2-low concept for 1+ and 2+ non amplified breast cancers lead to refine French practices for HER2 status assessment. The GEFPICS group, composed of expert pathologists, herein presents the latest French recommendations for HER2 status evaluation in breast cancer, taking into account the ASCO/CAP guidelines and introducing the HER2-low concept. In the era of personalized medicine, HER2 status assessment remains one of the most important biomarkers in breast cancer and its quality guaranties the optimal patients' care. French pathologists' commitment in theranostic biomarker quality is more than ever required to provide the most efficient cares in oncology.

Clinicopathologic breast cancer characteristics: predictions using global textural features of the ipsilateral breast mammogram

Radiomic features from mammograms have been shown to predict breast cancer (BC) risk; however, their contribution to BC characteristics has not yet been explored. This study included 184 women with BC between January 2012 and April 2017. A set of 33 global radiomic features were extracted from the ipsilateral breast mammogram. Associations between radiomic features and BC characteristics were investigated by univariate logistic regression analysis, and receiver-operating characteristic curve analysis was employed to evaluate the predictive performance of radiomic features. Histogram-based features (mean, 70th percentile, and 30th percentile) weakly differentiated progesterone status and tumor size (AUC range: 0.627-0.652, p ≤ 0.007). One gray level run length matrix (GLRLM)-based feature achieved an AUC of 0.68 in discriminating lymph-node status, and the fractal dimension achieved an AUC of 0.65 in predicting tumor size. After stratifying by age at BC diagnosis and baseline percent density (PD), the average predictive performance of the abovementioned features improved from 0.652 to 0.707 for baseline PD adjustment, and from 0.652 to 0.674 for age at BC diagnosis. Higher predictive performances were found for GLRLM-based features in predicting lymph-node status among younger women with high baseline PD (AUC range: 0.710-0.863), and for fractal features in predicting tumor size among patients with low PD (AUC: 0.704). Global radiomic features from the ipsilateral breast mammogram can predict lymph-node status and tumor size among certain categories of women and should be considered as a non-invasive tool for clinical decision-making in BC-affected women and for forecasting disease progression.

A simple digital image analysis system for automated Ki67 assessment in primary breast cancer

AIMS

Ki67 is a well-established immunohistochemical marker associated with cell proliferation that has prognostic and predictive value in breast cancer. Quantitative evaluation of Ki67 is traditionally performed by assessing stained tissue slides with light microscopy. Automated image analysis systems have become available and, if validated, could provide greater standardisation and improved precision of Ki67 scoring. Here, we aimed to evaluate the use of the Cognition Master Professional Suite (CogM) image analysis software, which is a simple system for scoring Ki67 in primary breast cancer samples.

METHODS AND RESULTS

Sections from 94 core-cut biopsies, 20 excision specimens and 29 pairs of core-cut biopsies and excision specimens were stained for Ki67 with MIB1 antibody and the Dako EnVision FLEX Detection System. Stained slides were scanned to convert them to digital data. Computer-based Ki67 scoring was performed with CogM. Manual Ki67 scoring assessment was conducted on previously stained sections from the same biopsies with a clinically validated system that had been calibrated against the risk of recurrence. A high correlation between manual and digital scores was observed [r_Cores  = 0.92, 95% confidence interval (CI) 0.87-0.94, P < 0.0001; r_Excisions  = 0.95, 95% CI 0.86-0.98, P < 0.0001] and there was no significant bias between them (P = 0.45). There was also a high correlation of Ki67 scores between paired core-cut biopsies and excision specimens when CogM was used (r = 0.78, 95% CI 0.59-0.89, P < 0.0001).

CONCLUSIONS

CogM image analysis allows for standardised automated Ki67 scoring that accurately replicates previously clinically validated and calibrated manual scores.

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.

The appropriate number of preoperative core needle biopsy specimens for analysis in breast cancer

Ultrasound (US)-guided core needle biopsy (CNB) has been recognized as a crucial diagnostic tool for breast cancer. However, there is a lack of guidance for hospitals that are not equipped with adjunctive US. The aim of this study was to assess the sensitivity, specificity, and experience of freehanded CNB in the outpatient department, and to determine the minimum number of tissue strips required to obtain concordance for estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor-2 (HER2), and tumor grade with the excised specimen.A prospective study was performed on 95 patients undergoing CNB and subsequent surgical procedures. The reliability of immunohistochemical assessments of the pathological type, tumor grade, ER, PR, and HER2 status in CNBs was compared with that of surgical specimens. Concordance between the CNBs and surgical samples was estimated as a percentage agreement, and analyzed using the chi-square test. A P < .05 was considered significant.The concordance rates of ER, PR, and HER2 status and tumor grade status between CNBs and surgically excised specimens were 97.9%, 91.6%, 82.1%, and 84.2%, respectively. The reliability of taking 2 tissue strips was similar to that of taking six tissue strips in distinguishing malignancy from benignancy, and determining the pathological type without the aid of US. Four tissue strips obtained by CNB showed good accuracy comparable to those obtained by surgical specimens in assessing ER, PR, and HER2 status and tumor grade.Two tissue strips obtained by CNB showed good accuracy in differentiating malignancy from benignancy, while at least 4 strips are recommended to obtain overall conformity of pathological biomarkers.

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.

A review of breast cancer pathology reports in Nigeria

Background

Diagnosis and treatment of cancer rely heavily on imaging, histopathology and molecular information. Incomplete or missing tumour information can hinder the delivery of high-quality care in oncology practice, especially in resource-limited countries. To evaluate the completeness of histopathology reporting in a real-world setting and identify areas for future cancer care delivery research efforts, we retrospectively analysed reports from patients diagnosed with breast cancer who received care at a high-volume oncology department at a hospital in Lagos, Nigeria.

Methods

Demographic, institutional and histopathology characteristics were retrospectively obtained from 1,001 patient records from 2007 to 2016. Completeness was defined as reporting five tumour features (tumour histology, tumour grade, laterality, oestrogen receptor (ER) or progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2)) for biopsy specimens and seven tumour features (tumour size, tumour histology, tumour grade, laterality, ER/PR, HER2 and lymph node involvement) for surgical specimens.

Results

The mean age of patients was 48.6 ± 11.7 years with a predominantly female population (99.3%). A majority of pathologic reports were produced after 2011, and two-thirds of the reports originated from centres or labs within Lagos, Nigeria (67.7%). Most reports documented primary site (98.0%) and specimen type (85.0%) while other characteristics were less often recorded. This led to substantial variation in reporting between biopsy (13.4%) and surgical (6.1%) specimens for an overall low pathology report completeness <10%.

Conclusion

The majority of patient records analysed lacked complete documentation of breast cancer histopathological characteristics commonly used in oncology practice. Our study highlights a need to identify and address the contributing factors for incomplete histopathological reporting in Nigeria and will guide future clinical programmatic developments.

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.

Hormone Receptor Loss in Breast Cancer: Molecular Mechanisms, Clinical Settings, and Therapeutic Implications

Hormone receptor-positive breast cancer (HR+ BC) accounts for approximately 75% of new BC diagnoses. Despite the undisputable progresses obtained in the treatment of HR+ BC in recent years, primary or acquired resistance to endocrine therapies still represents a clinically relevant issue, and is largely responsible for disease recurrence after curative surgery, as well as for disease progression in the metastatic setting. Among the mechanisms causing primary or acquired resistance to endocrine therapies is the loss of estrogen/progesterone receptor expression, which could make BC cells independent of estrogen stimulation and, consequently, resistant to estrogen deprivation or the pharmacological inhibition of estrogen receptors. This review aims at discussing the molecular mechanisms and the clinical implications of HR loss as a result of the therapies used in the neoadjuvant setting or for the treatment of advanced disease in HR+ BC patients.

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.

Structural Studies of Epithelial Mesenchymal Transition Breast Tissues

At the supramolecular level, the proliferation of invasive ductal carcinoma through breast tissue is beyond the range of standard histopathology identification. Using synchrotron small angle x-ray scattering (SAXS) techniques, determining nanometer scale structural changes in breast tissue has been demonstrated to allow discrimination between different tissue types. From a total of 22 patients undergoing symptomatic investigations, different category breast tissue samples were obtained in use of surgically removed tissue, including non-lesional, benign and malignant tumour. Structural components of the tissues were examined at momentum transfer values between q = 0.2 nm-1 and 1.5 nm-1. From the SAXS patterns, axial d-spacing and diffuse scattering intensity were observed to provide the greatest discrimination between the various tissue types, specifically in regard to the epithelial mesenchymal transition (EMT) structural component in malignant tissue. In non-lesional tissue the axial period of collagen is within the range 63.6-63.7 nm (formalin fixed paraffin embedded (FFPE) dewaxed) and 63.4 (formalin fixed), being 0.9 nm smaller than in EMT cancer-invaded regions. The overall intensity of scattering from cancerous regions is a degree of magnitude greater in cancer-invaded regions. Present work has found that the d-spacing of the EMT positive breast cancer tissue (FFPE (dewaxed)) is within the range 64.5-64.7 nm corresponding to the 9th and 10th order peaks. Of particular note in regard to formalin fixation of samples is that no alteration is observed to occur in the relative differences in collagen d-spacing between non-lesional and malignant tissues. This is a matter of great importance given that preserved-sample and also retrospective study of samples is greatly facilitated by formalin fixation. Present results indicate that as aids in tissue diagnosis SAXS is capable of distinguishing areas of invasion by disease as well as delivering further information at the supramolecular level.

Identifying breast cancer patients who require a double-check of preoperative core needle biopsy and postoperative surgical specimens to determine the molecular subtype of their tumor

Purpose

Core needle biopsy (CNB) is a widely used procedure for breast cancer diagnosis and analyzing results of immunohistochemistry (IHC). Several studies have shown concordance or discordance in IHC results between CNB and surgical specimens (SS). A double-check (CNB and SS) is inefficient and costly to perform a double-check on all patients. Therefore, it is important to determine which patients would benefit from a double-check.

Methods

We collected the medical records of patients who underwent breast cancer surgery at Pusan National University Yangsan Hospital between April 2009 and June 2018 (n = 620). Molecular subtypes were classified as follows by hormone receptors (HR) and human epidermal growth factor receptor-2 (HER2): HR+/HER2+, HR+/HER2−, HR−/HER2+, HR−/HER2−. Clinicopathological factors including age, obesity, histological grade, preoperative CEA, CA15-3, T stage, N stage, and menopausal status were assessed to determine whether they were associated with subtype change.

Results

Increasing histological grade (P < 0.001; odds ratio [OR], 3.693; 95% confidence interval [CI], 1.941–7.025), preoperative CEA ≥ 5 ng/mL (P =0.042; OR, 2.399; 95% CI, 1.009–5.707) and higher T stage (P = 0.015; OR, 2.241; 95% CI, 1.152–4.357) were significantly associated with subtype change. On multivariable analyses, subtype changes were more common in high-grade breast cancer (P < 0.001; OR, 1.077; 95% CI, 1.031–1.113) and CEA ≥ 5 (P = 0.032; OR, 2.658; 95% CI, 1.088–6.490).

Conclusion

Patients with moderate- to high-grade tumors or CEA ≥ 5 ng/mL are required a double-check to determine the molecular subtype of breast cancer.

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.

Clinicopathological Features and Disease Outcome in Breast Cancer Patients with Hormonal Receptor Discordance between Core Needle Biopsy and Following Surgical Sample

Background

There are limited data about how to manage patients with discordant hormonal receptor (HR) status between core needle biopsy (CNB) and following surgical sample (FSS). This study aimed to evaluate clinicopathological features and disease outcome for these HR discordance patients.

Patients and Methods

Invasive breast cancer patients with paired HR between CNB and FSS were retrospectively analyzed, being classified into three groups: HR positive, HR negative, and HR discordance. Patient characteristics, treatment decisions, and disease outcome were compared among above groups.

Results

A total of 1710 patients (1233 HR positive, 417 HR negative, and 60 HR discordance patients) were enrolled. Compared with the HR positive group, HR discordance patients were associated with more human epidermal growth factor receptor 2 positivity (P < 0.001) and higher Ki67 level (P = 0.001) tumors. The fraction of patients receiving adjuvant chemotherapy was 95.0% and 93.8% in the HR discordance or HR negative groups, much higher than in the HR positive group (66.7%, P < 0.001). Of 60 HR discordance patients, 34 (56.7%) received adjuvant endocrine therapy. The 5-year disease-free survival (DFS) rate was 90.4% for HR discordant patients, showing no statistical difference compared with HR positive (87.0%, P = 0.653) or HR negative (83.2%, P = 0.522) groups. For HR discordance patients, there was no difference in DFS between patients who received adjuvant endocrine therapy or not (P = 0.259).

Conclusions

HR discordance patients had similar tumor characteristics, adjuvant chemotherapy treatment, and DFS compared with HR negative patients. The benefit of endocrine therapy in these HR discordance patients is uncertain and deserves further clinical evaluation.

Electronic supplementary material

The online version of this article (10.1245/s10434-019-07480-y) contains supplementary material, which is available to authorized users.

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.

Changes of Tumor Infiltrating Lymphocytes after Core Needle Biopsy and the Prognostic Implications in Early Stage Breast Cancer: A Retrospective Study

PURPOSE

The purpose of this study was to investigate the changes of tumor infiltrating lymphocytes (TILs) between core needle biopsy (CNB) and surgery removed sample (SRS) in early stage breast cancer patients and to identify the correlating factors and prognostic significance of TILs changes.

Materials and Methods

A retrospective study was carried out on 255 patients who received CNB and underwent surgical resection for invasive breast cancer. Stromal TILs levels of CNB and SRS were evaluated respectively. Tumors with ≥50% stromal TILs were defined as lymphocyte-predominant breast cancer (LPBC). Clinicopathological variables were analyzed to determine whether there were factors associated with TILs changes. Log-rank tests and Cox proportional hazards models were used to analyze the influences of TILs and TILs changes on survival.

RESULTS

SRS-TILs (median, 10.0%) were significant higher than CNB-TILs (median, 5.0%; p<0.001). Younger age (<60 years, p=0.016) and long surgery time interval (STI, ≥4 days; p=0.003) were independent factors correlating with higher TILs changes. CNB-LPBC patients showed better breast cancer-free interval (BCFI, p=0.021) than CNB-non-LPBC (CNB-nLPBC) patients. Patients were categorized into four groups according to the LPBC change pattern from CNB to SRS: LPBC→LPBC, LPBC→nLPBC, nLPBC→LPBC, and nLPBC→nLPBC, with estimated 5-year BCFI 100%, 100%, 69.7%, and 86.0% (p=0.016). nLPBC→LPBC pattern was an independent prognostic factor of worse BCFI (hazard ratio, 2.19; 95% confidence interval, 1.06 to 4.53; p=0.035) compared with other patterns.

CONCLUSION

TILs were significantly higher in SRS than in CNB. Higher TILs changes were associated with younger age and long STI. Changing from nLPBC to LPBC after CNB indicated a worse BCFI, which needs further validation.

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.

Neoadjuvant chemotherapy reduces the expression rates of ER, PR, HER2, Ki67, and P53 of invasive ductal carcinoma

To analyze whether neoadjuvant chemotherapy (NAC) changes the expression rates of invasive ductal carcinoma (IDC) markers: estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2), Ki67, and P53.This was a retrospective study of 112 IDC patients who underwent NAC (docetaxel+epirubicin/pirarubicin+cyclophosphamide) but without pathological complete response (pCR) in 2012 to 2013 at the First Affiliated Hospital of Chongqing Medical University. The IDC subtypes and tumor protein markers were analyzed by immunohistochemistry (IHC). Specific changes in tumor protein markers before/after NAC were compared.The decrease in the positive rate of Ki-67 was the most significant, from 75.9% before NAC to 41.1% after NAC (P < .001). The positive rate of HER2 decreased from 42.0% before NAC to 32.1% after NAC (P = .04). The positive rate of ER decreased from 66.1% before NAC to 56.2% after NAC (P = .04). Increased number of metastatic lymph nodes (P = .006) and body mass index (BMI) (P = .028) seemed to be related to conversion of PR (positive to negative). There was statistical association between the Ki-67 (positive to negative) with the age greater or equal to 50 (P = .015). The BMI greater or equal to 24 (P = .021), age greater or equal to 50 (P = .047), and blood type A (P = .038) were independently associated with conversion of P53 (positive to negative). The BMI greater or equal to 24 (P = .004), number of metastatic lymph nodes greater or equal to 1 (P = .029) and TNM stages I-II (P = .008) were statistically associated with change of HER2 (positive to negative).In patients without pCR, NAC leads to changes in Ki-67, HER2, and hormone receptor (HR) expression. Age, BMI, number of metastatic lymph nodes, and TNM stage are associated with some changes of markers.

Prognostic value of pathologic complete response and the alteration of breast cancer immunohistochemical biomarkers after neoadjuvant chemotherapy

Neoadjuvant chemotherapy(NCT) has become the standard treatment for breast cancer. The information about the tumor's sensitivity to chemotherapy and prognostic significance based on response to therapy can be provided after individualized neoadjuvant treatment. The biomarkers are key factors in the decision-making process regarding treatment as well as important prognostic indicators. Studies have shown that patients who achieve pathological complete response(pCR) after NCT have a better prognosis. For patients who do not achieve pCR, the pathological characteristics of the residual tumor can make an effect on the survival. Furthermore, the immunohistochemical (IHC) markers of the residual diseases after primary systemic therapy might be different from the primary tumor. Estrogen receptor (ER), progesterone receptor (PR), and Ki67 can usually change after NCT, while human epidermal growth factor receptor 2(HER2) seems to be more stable. The relationship between changes in breast cancer molecular biomarkers and the prognosis after neoadjuvant therapy is not yet clear. The article will make a review about it.

Human Epidermal Growth Factor Receptor 2 Testing in Breast Cancer: American Society of Clinical Oncology/College of American Pathologists Clinical Practice Guideline Focused Update

PURPOSE.—

To update key recommendations of the American Society of Clinical Oncology (ASCO)/College of American Pathologists (CAP) human epidermal growth factor receptor 2 (HER2) testing in breast cancer guideline.

METHODS.—

Based on the signals approach, an Expert Panel reviewed published literature and research survey results on the observed frequency of less common in situ hybridization (ISH) patterns to update the recommendations.

RECOMMENDATIONS.—

Two recommendations addressed via correspondence in 2015 are included. First, immunohistochemistry (IHC) 2+ is defined as invasive breast cancer with weak to moderate complete membrane staining observed in >10% of tumor cells. Second, if the initial HER2 test result in a core needle biopsy specimen of a primary breast cancer is negative, a new HER2 test may (not "must") be ordered on the excision specimen based on specific clinical criteria. The HER2 testing algorithm for breast cancer is updated to address the recommended workup for less common clinical scenarios (approximately 5% of cases) observed when using a dual-probe ISH assay. These scenarios are described as ISH group 2 ( HER2/chromosome enumeration probe 17 [CEP17] ratio ≥2.0; average HER2 copy number <4.0 signals per cell), ISH group 3 ( HER2/CEP17 ratio <2.0; average HER2 copy number ≥6.0 signals per cell), and ISH group 4 ( HER2/CEP17 ratio <2.0; average HER2 copy number ≥4.0 and <6.0 signals per cell). The diagnostic approach includes more rigorous interpretation criteria for ISH and requires concomitant IHC review for dual-probe ISH groups 2 to 4 to arrive at the most accurate HER2 status designation (positive or negative) based on combined interpretation of the ISH and IHC assays. The Expert Panel recommends that laboratories using single-probe ISH assays include concomitant IHC review as part of the interpretation of all single-probe ISH assay results.

Ancillary Prognostic and Predictive Testing in Breast Cancer: Focus on Discordant, Unusual, and Borderline Results

Ancillary testing in breast cancer has become standard of care to determine what therapies may be most effective for individual patients with breast cancer. Single-marker tests are required on all newly diagnosed and newly metastatic breast cancers. Markers of proliferation are also used, and include both single-marker tests like Ki67 as well as panel-based gene expression tests, which have made more recent contributions to prognostic and predictive testing in breast cancers. This review focuses on pathologist interpretation of these ancillary test results, with a focus on expected versus unexpected results and troubleshooting borderline, unusual, or discordant results.

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.

Human Epidermal Growth Factor Receptor 2 Testing in Breast Cancer: American Society of Clinical Oncology/College of American Pathologists Clinical Practice Guideline Focused Update

Purpose To update key recommendations of the American Society of Clinical Oncology/College of American Pathologists human epidermal growth factor receptor 2 (HER2) testing in breast cancer guideline. Methods Based on the signals approach, an Expert Panel reviewed published literature and research survey results on the observed frequency of less common in situ hybridization (ISH) patterns to update the recommendations. Recommendations Two recommendations addressed via correspondence in 2015 are included. First, immunohistochemistry (IHC) 2+ is defined as invasive breast cancer with weak to moderate complete membrane staining observed in > 10% of tumor cells. Second, if the initial HER2 test result in a core needle biopsy specimen of a primary breast cancer is negative, a new HER2 test may (not "must") be ordered on the excision specimen based on specific clinical criteria. The HER2 testing algorithm for breast cancer is updated to address the recommended work-up for less common clinical scenarios (approximately 5% of cases) observed when using a dual-probe ISH assay. These scenarios are described as ISH group 2 ( HER2/chromosome enumeration probe 17 [CEP17] ratio ≥ 2.0; average HER2 copy number < 4.0 signals per cell), ISH group 3 ( HER2/CEP17 ratio < 2.0; average HER2 copy number ≥ 6.0 signals per cell), and ISH group 4 ( HER2/CEP17 ratio < 2.0; average HER2 copy number ≥ 4.0 and < 6.0 signals per cell). The diagnostic approach includes more rigorous interpretation criteria for ISH and requires concomitant IHC review for dual-probe ISH groups 2 to 4 to arrive at the most accurate HER2 status designation (positive or negative) based on combined interpretation of the ISH and IHC assays. The Expert Panel recommends that laboratories using single-probe ISH assays include concomitant IHC review as part of the interpretation of all single-probe ISH assay results. Find additional information at www.asco.org/breast-cancer-guidelines .

Delay to Formalin Fixation (Cold Ischemia Time) Effect on Breast Cancer Molecules

OBJECTIVES

The gold standard of examining breast biomarkers, including estrogen receptor (ER)/progesterone receptor (PR)/human epidermal growth factor receptor 2 (HER2)/Ki-67, is to perform these assays on formalin-fixed, paraffin-embedded tissue. However, preanalytical variables may confound these assays. One of these factors is delay to formalin fixation (DFF). The purpose of this review is to evaluate each study that investigated the effect of DFF on breast biomarkers and other molecules.

METHODS

Thirteen primary research articles were identified by the literature search. The credibility of the studies was judged based on the degree of controlling other confounding factors. Nine studies had a prospective design with a high number of controlled variables.

RESULTS

Most of the studies concluded that DFF had an effect on ER/PR/HER2. Some of these studies showed that DFF had negative effect on other markers used either clinically or for research purposes.

CONCLUSIONS

The vast majority of the studies agree that DFF has negative effect on breast biomarkers.

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.

The Reliability of Core-Needle Biopsy in Assessment of Hormone Receptor, HER2, and Ki-67 in Breast Carcinoma

Objective:

The purpose of this study was to compare the estrogen receptor (ER), progesterone receptor (PgR), and human epidermal growth factor receptor 2 (HER2) status and Ki-67 index by immunohistochemical (IHC) analysis in breast carcinoma to determine the level of concordance between core-needle biopsy (CNB) and surgical specimens.

Summary of Background:

Accurate preoperative diagnosis of a breast lesion has recently been considered essential to the treatment strategy to achieve optimal treatment without delay. However, the reliability of using CNB specimens for IHC assessment is in relatively small number of cases and differing results between previous studies.

Methods:

The patients included in this study were 255 patients with primary breast carcinoma who had CNB and subsequent surgical resection at the Hospital of Dokkyo Medical University between 2010 and 2016. We compare the ER, PgR, HER2 status, and Ki-67 index by IHC analysis in breast carcinoma between CNB and surgical specimens.

Results:

There was a concordance rate between the ER, PgR, HER2, and Ki-67 IHC assessment of CNB and surgical specimens in 99.0%, 92.1%, 86.3%, and 91.5%, respectively. We also found small numbers of discordant cases in the estimation for which a discrepancy in determination led to a change in treatment.

Conclusions:

Our results do not entirely invalidate the use of CNB for assessment if they are the only source of tumor tissue available, but suggest a more cautious approach in their interpretation when clinical decisions are being made.

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.

Neoadjuvant Chemotherapy in Triple Negative Breast Cancer: An Observational Study

Triple negative breast cancer (TNBC) is a phenotype of breast cancer with aggressive clinical behavior. Because of the absence of optimal treatment, the prognosis of this disease is poor. The main purpose of this study was to detect the response to neoadjuvant chemotherapy (NACT) in a TNBC cohort and compare the long-term survival between patients with and without pathological complete response (pCR). A total of 53 patients diagnosed with TNBC from 2005 to 2013 who received NACT at the University Hospital Birmingham were enrolled in this study. Overall survival (OS) and progression-free survival (PFS) were compared between the pCR group and non-pCR group. Demographic information and clinical or pathologic parameters were also analyzed to explore potential predictive and prognostic factors. Fourteen patients (26.4%) achieved pCR to NACT. In univariate analysis, patients with pCR had longer PFS time (p = 0.013) and OS time (p = 0.054) compared with their counterparts without pCR. In multivariate analysis, the existence of lymphovascular invasion (LVI) significantly reduced OS (HR = 17.404, 95% CI = 2.923–103.644) and PFS (HR = 7.776, 95% CI = 1.645–36.753). The achievement of pCR to NACT can significantly postpone the incidence of disease progression in patients with TNBC. There is not enough evidence showing its influence on ultimate survival. LVI may be a more potent prognostic factor than pCR in the TNBC cohort.

Discrepancies in central review re-testing of patients with ER-positive and HER2-negative breast cancer in the OPTIMA prelim randomised clinical trial

Background:

There is limited data on results of central re-testing of samples from patients with invasive breast cancer categorised in their local hospital laboratories as oestrogen receptor (ER) positive and human epidermal growth factor receptor homologue 2 (HER2) negative.

Methods:

The Optimal Personalised Treatment of early breast cancer usIng Multiparameter Analysis preliminary study (OPTIMA prelim) was the feasibility phase of a randomised controlled trial to validate the use of multiparameter assay-directed chemotherapy decisions in the UK National Health Service (NHS). Eligibility criteria included ER positivity and HER2 negativity. Central re-testing of receptor status was mandatory.

Results:

Of the 431 patients tested centrally, discrepant results between central and local laboratory results were identified in only 19 (4.4% 95% confidence interval 2.5–6.3%) patients (with 21 tumours). On central review, seven patients had cancers that were ER-negative (1.6%) and 13 (3.0%) patients with 15 tumours had HER2-positive disease, including one tumour discrepant for both biomarkers.

Conclusions:

Central re-testing of receptor status of invasive breast cancers in the UK NHS setting shows a high level of reproducibility in categorising tumours as ER-positive and HER2-negative, and raises questions regarding the cost effectiveness and clinical value of central re-testing in this sub-group of breast cancers in this setting.

A novel semi-robotized device for high-precision 18F-FDG-guided breast cancer biopsy

PURPOSE

To assess the 3D geometric sampling accuracy of a new PET-guided system for breast cancer biopsy (BCB) from areas within the tumour with high ¹⁸F-FDG uptake.

MATERIALS AND METHODS

In the context of the European Union project MammoCare, a prototype semi-robotic stereotactic prototype BCB-device was incorporated into a dedicated high resolution PET-detector for breast imaging. The system consists of 2 stacked rings, each containing 12 plane detectors, forming a dodecagon with a 186mm aperture for 3D reconstruction (1mm³ voxel). A vacuum-assisted biopsy needle attached to a robot-controlled arm was used. To test the accuracy of needle placement, the needle tip was labelled with ¹⁸F-FDG and positioned at 78 target coordinates distributed over a 35mm×24mm×28mm volume within the PET-detector field-of-view. At each position images were acquired from which the needle positioning accuracy was calculated. Additionally, phantom-based biopsy proofs, as well as MammoCare images of 5 breast cancer patients, were evaluated for the 3D automated locating of ¹⁸F-FDG uptake areas within the tumour.

RESULTS

Needle positioning tests revealed an average accuracy of 0.5mm (range 0-1mm), 0.6mm (range 0-2mm), and 0.4mm (range 0-2mm) for the x/y/z-axes, respectively. Furthermore, the MammoCare system was able to visualize and locate small (<10mm) regions with high ¹⁸F-FDG uptake within the tumour suitable for PET-guided biopsy after being located by the 3D automated application.

CONCLUSIONS

Accuracy testing demonstrated high-precision of this semi-automatic 3D PET-guided system for breast cancer core needle biopsy. Its clinical feasibility evaluation in breast cancer patients scheduled for neo-adjuvant chemotherapy will follow.

Modern therapies and iatrogenic changes in breast pathology

Iatrogenic changes within the breast can provide challenges for the histopathologist in routine practice. Diagnostic procedures, such as core biopsies, result in reactive changes and can cause displacement of benign and malignant cells, the interpretation of which may cause difficulties in the resection specimen. Breast augmentation surgery with implants or injection of fillers, performed for cosmetic reasons or as part of a reconstructive process following removal of breast cancer, also produces reactive changes locally and at distant sites that may mimic cancer. The entity of implant-associated anaplastic large-cell lymphoma is now well recognized, with progress in our understanding of the underlying biological factors that drive its development. Chemotherapy and radiotherapy used in the treatment of breast cancer causes characteristic changes in normal breast tissue, and can alter the histological appearance and receptor status of the tumour. Radiotherapy to the breast, for breast cancer or childhood malignancies, increases the risk of developing a secondary malignancy in the breast long after treatment. In this review, we describe some of the iatrogenic changes that may be seen in histological specimens from the breast.

Influence of decalcification procedures on immunohistochemistry and molecular pathology in breast cancer

Distant breast cancer metastases are nowadays routinely biopsied to reassess receptor status and to isolate DNA for sequencing of druggable targets. Bone metastases are the most frequent subgroup. Decalcification procedures may negatively affect antigenicity and DNA quality. We therefore evaluated the effect of several decalcification procedures on receptor status and DNA/RNA quality. In 23 prospectively collected breast tumors, we compared ERα, PR and HER2 status by immunohistochemistry in (non-decalcified) tissue routinely processed for diagnostic purposes and in parallel tissue decalcified in Christensen's buffer with and without microwave, EDTA and Formical-4. Furthermore, HER2 fluorescence in situ hybridization and DNA/RNA quantity and quality were assessed. We found that the percentage of ERα-positive cells were on average lower in EDTA (P=0.049) and Formical-4 (P=0.047) treated cases, compared with controls, and PR expression showed decreased antigenicity after Christensen's buffer treatment (P=0.041). Overall, a good concordance (weighted kappa) was seen for ERα, PR and HER2 immunohistochemistry when comparing the non-decalcified control tissues with the decalcified tissues. For two patients (9%), there was a potential influence on therapeutic decision making with regard to hormonal therapy or HER2-targeted therapy. HER2 fluorescence in situ hybridization interpretation was seriously hampered by Christensen's buffer and Formical-4, and DNA/RNA quantity and quality were decreased after all four decalcification procedures. Validation on paired primary breast tumor specimens and EDTA-treated bone metastases showed that immunohistochemistry and fluorescence in situ hybridization were well assessable and DNA and RNA yield and quality were sufficient. With this, we conclude that common decalcification procedures have only a modest negative influence on hormone and HER2 receptor immunohistochemistry in breast cancer. However, they may seriously affect DNA/RNA-based diagnostic procedures. Overall, EDTA-based decalcification is therefore to be preferred as it best allows fluorescence in situ hybridization and DNA/RNA isolation.