Impact of breast cancer risk factors on clinically relevant prognostic biomarkers for primary breast cancer.

PURPOSE: In addition to impacting incidence, risk factors for breast cancer may also influence recurrence and survival from the disease. However, it is unclear how these factors affect combinatorial biomarkers for aiding treatment decision-making in breast cancer. METHODS: Patients were 8179 women with histologically confirmed invasive breast cancer, diagnosed and treated in a large cancer hospital in Beijing, China. Individual clinicopathological (tumor size, grade, lymph nodes) and immunohistochemical (IHC: ER, PR, HER2, KI67) markers were used to define clinically relevant combinatorial prognostic biomarkers, including the Nottingham Prognostic Index (NPI: combining size, grade, nodes) and IHC4 score (combining ER, PR, HER2, KI67). Odds ratios (ORs) and 95% confidence intervals (CIs) for associations between breast cancer risk factors and quartiles (Q1-Q4) of NPI and IHC4 were assessed in multivariable polytomous logistic regression models. RESULTS: Overall, increasing parity (ORtrend(95% CI) = 1.20(1.05-1.37);Ptrend = 0.007), overweight (OR(95% CI)vs normal = 1.60(1.29-1.98)), and obesity (OR(95% CI) vs normal = 2.12(1.43-3.14)) were associated with higher likelihood of developing tumors with high (Q4) versus low (Q1) NPI score. Conversely, increasing age (ORtrend(95% CI) = 0.75(0.66-0.84);Ptrend < 0.001) and positive family history of breast cancer (FHBC) (OR(95% CI) = 0.66(0.45-0.95)) were inversely associated with NPI. Only body mass index (BMI) was associated with IHC4, with overweight (OR(95% CI) vs normal = 0.82(0.66-1.02)) and obese (OR(95% CI) vs normal = 0.52(0.36-0.76)) women less likely to develop high IHC4 tumors. Notably, elevated BMI was associated with higher NPI irrespective of hormone receptor-expression status. CONCLUSIONS: Our findings indicate that factors affecting breast cancer incidence, particularly age, parity, FHBC, and BMI, may impact clinically relevant prognostic biomarkers with implications for surveillance, prognostication, and counseling.

Prognostic Value of Modified IHC4 Score in Patients with Estrogen Receptor-Positive Metastatic Breast Cancer.

BACKGROUND: This study aimed to investigate whether an immunohistochemical prognostic model (IHC4 score) can predict the prognosis and the chemotherapy benefit in patients with estrogen receptor-positive (ER+)/human epidermal growth receptor 2-negative (HER2-) metastatic breast cancer (MBC). MATERIALS AND METHODS: We developed a method to calculate the modified IHC4 (mIHC4) scores based on routine pathological reports and compared them with the original IHC4 scores that were much more difficult to calculate. Univariate and multivariate analyses were used to study the prognostic factors of progression-free survival (PFS) and overall survival (OS). The predictive value of mIHC4 score was also investigated. RESULTS: The Sun Yat-sen Memorial Hospital data set included 315 patients with newly diagnosed ER+ MBC with a median follow-up of 25.6 months. Univariate and multivariate analysis showed that higher mIHC4 scores in metastatic lesions, but not the ones in primary tumors, were significantly associated with worse PFS and OS. The prognostic value of mIHC4 scores for PFS was validated using an independent Chinese Society of Clinical Oncology- Breast Cancer (CSCO-BC) data set. More importantly, subpopulation treatment effect pattern plot analysis showed that first-line endocrine therapy achieved better PFS and OS than chemotherapy in low-risk patients with ER+/HER2- MBC, whereas first-line chemotherapy was associated with improved PFS and OS compared with endocrine therapy in high-risk ones. The predictive value of mIHC4 score for PFS in selecting first-line endocrine therapy versus chemotherapy was also confirmed in the CSCO-BC data set. CONCLUSION: mIHC4 scores in metastatic lesions are prognostic for the PFS and OS in patients with ER+ MBC. Low or high mIHC4 score may indicate the survival benefit in choosing first-line endocrine therapy or chemotherapy in patients with ER+/HER2- MBC, respectively. IMPLICATIONS FOR PRACTICE: The modified IHC4 (mIHC4) score is easy to implement and able to predict patients with advanced and/or metastatic breast cancer. In addition, with the help of the mIHC4 score, physicians might be able to recommend chemotherapy or endocrine therapy as the first-line treatment for patients with high and low risk as predicted by the mIHC4 score.

Relationship between IHC4 score and response to neo-adjuvant chemotherapy in estrogen receptor-positive breast cancer.

AIMS: To determine whether IHC4 score assessed on pre-treatment core biopsies (i) predicts response to neo-adjuvant chemotherapy in ER-positive (ER+) breast cancer; (ii) provides more predictive information than Ki67 alone. METHODS: 113 patients with ER+ primary breast cancer treated with neo-adjuvant chemotherapy at the Royal Marsden Hospital between 2002 and 2010 were included in the study. Pathologic assessment of the excision specimen was made for residual disease. IHC4 was determined on pre-treatment core biopsies, blinded to clinical outcome, by immunohistochemistry using quantitative scoring of ER (H-score), PgR (%) and Ki67 (%). Determination of HER2 status was made by immunohistochemistry and fluorescent in situ hybridization for 2+ cases. IHC4 and Ki67 scores were tested for their association with pathological complete response (pCR) rate and residual cancer burden (RCB) score. RESULTS: 18 (16%) of the 113 patients and 8 (9%) of the 88 HER2-ve cases achieved pCR. Ki67 and IHC4 score were both positively associated with achievement of pCR (P < 10-7 and P < 10-9, respectively) and RCB0+1 (P < 10-5 and P < 10-9, respectively) following neo-adjuvant chemotherapy in all patients. Rates of pCR+RCB1 were 45 and 66% in the highest quartiles of Ki67 and IHC4 scores, respectively. In ER+HER2-ve cases, pCR+RCB1 rates were 35% and in the highest quartile of both Ki67 and IHC4. There were no pCRs in the lower half of IHC4 or Ki67 scores. CONCLUSIONS: IHC4 was strongly predictive of pCR or near pCR in ER+ breast cancers following neo-adjuvant chemotherapy. Ki67 was an important component of this predictive ability, but was not as predictive as IHC4.

Reducing chemotherapy use in clinically high-risk, genomically low-risk pN0 and pN1 early breast cancer patients: five-year data from the prospective, randomised phase 3 West German Study Group (WSG) PlanB trial.

BACKGROUND: The prospective phase 3 PlanB trial used the Oncotype DX® Recurrence Score® (RS) to define a genomically low-risk subset of clinically high-risk pN0-1 early breast cancer (EBC) patients for treatment with adjuvant endocrine therapy (ET) alone. Here, we report five-year data evaluating the prognostic value of RS, Ki-67, and other traditional clinicopathological parameters. METHODS: A central tumour bank was prospectively established within PlanB. Following an early amendment, hormone receptor (HR)+ , pN0-1 RS ≤ 11 patients were recommended to omit chemotherapy. Patients with RS ≥ 12, pN2-3, or HR-negative/HER2-negative disease were randomised to anthracycline-containing or anthracycline-free chemotherapy. Primary endpoint: disease-free survival (DFS). PlanB Clinicaltrials.gov identifier: NCT01049425. FINDINGS: From 2009 to 2011, PlanB enrolled 3198 patients (central tumour bank, n = 3073) with the median age of 56 years, 41.1% pN+, and 32.5% grade 3 EBC. Chemotherapy was omitted in 348/404 (86.1%) eligible RS ≤ 11 patients. After 55 months of median follow-up, five-year DFS in ET-treated RS ≤ 11 patients was 94% (in both pN0 and pN1) versus 94% (RS 12-25) and 84% (RS > 25) in chemotherapy-treated patients (p < 0.001); five-year overall survival (OS) was 99 versus 97% and 93%, respectively (p < 0.001). Nodal status, central/local grade, tumour size, continuous Ki-67, progesterone receptor (PR), IHC4, and RS were univariate prognostic factors for DFS. In a multivariate analysis including all univariate prognostic markers, only pN2-3, central and local grade 3, tumour size >2 cm, and RS, but not IHC4 or Ki-67 were independent adverse factors. If RS was excluded, IHC4 or both Ki-67 and PR entered the model. The impact of RS was particularly pronounced in patients with intermediate Ki-67 (>10%, <40%) tumours. INTERPRETATION: The excellent five-year outcomes in clinically high-risk, genomically low-risk (RS ≤ 11) pN0-1 patients without adjuvant chemotherapy support using RS with standardised pathology for treatment decisions in HR+ HER2-negative EBC. Ki-67 has the potential to support patient selection for genomic testing.

Advancing breast cancer subtyping: optimizing immunohistochemical staining classification with insights from real-world Taiwanese data.

Gene expression signatures provide valuable information to guide postoperative treatment in breast cancer (BC) patients. However, genetic tests are prohibitively expensive for the majority of BC patients. Immunohistochemical staining (IHC) subtype classification system has been widely used for treatment guideline and is affordable to most BC patients. We aimed to revise immunohistochemical staining (IHC) subtyping to better match gene expression-based Prediction Analysis of Microarray 50 (PAM50) subtyping. Real world data of 372 BC patients were recruited in the Tri-Service General Hospital between Jan 2019 and Dec 2021. Clinical pathological information, blood, twelve pathological tissue slide samples, and fresh surgical tumor specimens were collected to examine IHC and PAM50. Current IHC subtyping (cIHC) tends to misclassify PAM50-based luminal A (lum A) to luminal B (lum B) by 35.81%, PAM50-lum B to PAM50-lum A by 9.09%, PAM50-Her2-enriched to lum B by 61.11%, PAM50-based Her2-enriched to lum B by 61.11%, and PAM50-based basal-like to lum B by 33.33%. We used random forest to identify estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (Her2), and Ki-67 status as the best indicators for revised IHC subtyping (rIHC4) and revised the classification rules by stratified analysis and prediction efficacy. rIHC4 increased the concordance rate for PAM50 subtypes from 68.3% to 74.7%. Both sensitivity and precision increased in most rIHC4 subtypes. Sensitivity increased from 33.3% to 87.4% in the Her2-enriched subtype; precision increased more evidently in the basal-like and lum B subtypes, from 71.4% to 83.3% and 57% to 65.1%, respectively. Our rIHC4 subtyping improved consistency with the PAM50 subtype, which could improve clinical management of BC patients without increasing medical expense.

Conventional Tools for Predicting Satisfactory Response to Neoadjuvant Chemotherapy in HR+/HER2- Breast Cancer Patients.

Aim: The aim of the study was to assess the role of Magee Equation 3 (MagEq3), IHC4 score, and HER2-low status in predicting "satisfactory response (SR)" to neoadjuvant chemotherapy (NAC) in HR+/HER2- breast cancer (BC) patients. Methods: In a retrospective study, female patients of any age with T1-4, N0-2, M0 HR+/HER2- BC who received NAC and underwent adequate locoregional surgical treatment were included. Patients were grouped according to 2 outcomes: (a) overall response to NAC in breast and axilla by using residual cancer burden (RCB) criteria and (b) axillary downstaging after NAC by using N staging. 2 cohorts for overall response were overall SR (RCB 0-1) and no SR (RCB 2-3). On the other hand, for axillary downstaging, 2 cohorts constituted from axillary SR (ypN0 and ypN0i+) and no SR (ypNmic-N3). MagEq3 and IHC4 scores were calculated from their pathological tumor slides in each patient. HER2 status was categorized as either "no" or "low." In addition, patient age, family history, tumor histology, stage at admission, and Ki-67 status were compared between cohorts according to predefined outcomes. Results: In a total of 230 BC patients, 228 patients were included to compare according to their RCB levels. The mean age of patients with overall SR was significantly lower than those without. Patients with high Ki-67 expression, high (>30) MagEq3 score, high ICH4 quartile, and HER2-low status had significantly more overall SR. On the other hand, only patients with high Ki-67 expression had significantly more axillary SR. MagEq3 score levels, ICH4 quartiles, and HER2 status were similar between patients with axillary SR and not. Conclusion: MagEq3 and IHC4 tools seemed to be useful to predict those HR+/HER2- BC patients who are most likely to get benefit from NAC. But, only high Ki-67 expression level significantly predicted satisfactory axillary downstaging in HR+/HER2- BC patients.

Comparison of Different Molecular Subtypes with 14% Ki-67 Cut-off Threshold in Breast Cancer Patients of Pakistan- An Indication of Poor Prognosis.

BACKGROUND: Ki-67 is a proliferation marker that is used not only to categorize patients in luminal A and B subtypes of breast cancers, but also to determine the aggressiveness of the disease in triple negative and human epidermal growth factor 2 (HER2) over expressed molecular subtypes. The present study was designed to evaluate the role of Ki-67 with cut off value of 14% in molecular subgroups and its association with patient prognosis. METHODS: Immunostaining was performed on histopathologically confirmed sections (n = 278) to assess expression of Ki-67, estrogen receptor (ER), progesterone receptor (PR) and HER2. Immunoreactivity of molecules was recorded as percentage scoring. RESULTS: Adopting a cut off value of 14%, Ki-67 was high in 88%of the cases included in the study. High Ki-67 was significantly associated with pathological parameters including histological grade, advanced stage and nodal/distant metastasis. Immunoexpression of ER, PR and HER2 also showed strong correlation with high expression of Ki-67. Based on the St. Gallen classification, the cases were categorized into luminal A (10%) and luminal B (51%), triple negative (20%) and HER2 enriched (18%). Ki-67 index was also significantly high in 98% of HER2 enriched and 95% of TNBC patients. Interestingly, Ki-67 score with cut off value of 14% proved to be significant in deciphering prognosis in luminal patients. Moreover, high expression of Ki-67 also proved to be a marker of poor prognosis, especially in triple negative patients. CONCLUSION: We suggest that utilization of IHC4 status i.e. ER, PR, HER2 and Ki-67 along with pathological findings and molecular subtyping can considerably affect clinical as well as therapeutic decisions.

The IHC4+C score: an affordable and reproducible non-molecular decision-aid in hormone receptor-positive breast cancer. Does it still hold value for patients in 2020?

AIM: The majority of women diagnosed with early breast cancer have hormone-receptor positive (HR+)/HER2-negative disease. Adjuvant endocrine therapy provides substantial risk reduction benefits in virtually all patients. The role of adjuvant chemotherapy in certain subsets of patients is equivocal. This paper sought to evaluate the role of the IHC4+C score to aid this clinical decision in addition to providing an overview of the current molecular and non- molecular tools available in the adjuvant setting. METHODS: This prospective study included 53 post-operative HR+/HER2- negative early breast cancer patients selected from the multidiscipliniary team meeting between August 2017 and January 2020. IHC4+C testing was requested by clinicians for patients in whom the availability of the score may have impacted adjuvant decision-making. Adjuvant treatment decisions were recorded at three time points (prior and post IHC4+C scoring as well as the patient's final decision). The primary goal was the proportion of patients who were spared chemotherapy following the availability of IHC4+C scores to impact on clinicians' recommendations for adjuvant systemic therapy. RESULTS: A total of 34 patients (64%) were initially recommended to undergo chemotherapy or to consider chemotherapy. With the availability of the IHC4+C score, only 17 patients (32%) underwent chemotherapy, demonstrating a substantial reduction in the frequency of chemotherapy prescribing. CONCLUSION: This study demonstrates that when utilized appropriately in a multidisciplinary setting, the IHC4+C algorithm is an alternative, reproducible and affordable tool with a proven capacity to stratify risk and to spare a large proportion of patients from undergoing chemotherapy.

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.

A combination of Nottingham prognostic index and IHC4 score predicts pathological complete response of neoadjuvant chemotherapy in estrogen receptor positive breast cancer.

Pathologic complete response (pCR) prediction after neoadjuvant chemotherapy (NAC) is important for clinical decision-making in breast cancer. This study investigated the predictive value of Nottingham prognostic index (NPI), Immunohistochemical four (IHC4) score and a new predictive index combined with them in estrogen-positive (ER+) breast cancer following NAC. We retrospectively gathered clinical data of 739 ER+ breast cancer patients who received NAC from two cancer centers. We developed a new predictive biomarker named NPI+IHC4 to predict pCR in ER+ breast cancer in a training set (n=443) and validated it in an external validation set (n=296). The results showed that a lower IHC4 score, NPI and NPI+IHC4 were significantly associated a high pCR rate in the entire cohort. In the study set, NPI+IHC4 showed a better sensitivity and specificity for pCR prediction (AUC 0.699, 95% CI 0.626-0.772) than IHC4 score (AUC 0.613, 95% CI 0.533-0.692), NPI (AUC 0.576, 95% CI 0.494-0.659), tumor size (AUC 0.556, 95% CI 0.481-0.631) and TNM stage (AUC 0.521, 95% CI 0.442-0.601). In the validation set, NPI+IHC4 had a better predictive value for pCR (AUC 0.665, 95% CI 0.579-0.751) than IHC4 score or NPI alone. In addition, ER+ patients with lower IHC4, NPI and NPI+IHC4 scores had significantly better DFS in both study and validation sets. In summary, NPI+IHC4 can predict pCR following NAC and prognosis in ER+ breast cancer, which is cost-effect and potentially more useful in guiding decision-making regarding NAC in clinical practice. Further validation is needed in prospective clinical trials with larger cohorts of patients.

Correlation of clinicopathological outcomes with changes in IHC4 status after NACT in locally advanced breast cancers: do pre-NACT ER/PR status act as better prognosticators?

BACKGROUND: Following neoadjuvant chemotherapy (NACT) for breast cancer, changes in estrogen receptor (ER), progesterone receptor (PR), HER2 status, and Ki-67 index (IHC4 status) and its correlation with pathological complete response (pCR) or relapse-free survival (RFS) rates could lead to better understanding of tumor management. PATIENTS AND METHODS: Pre- and post-NACT IHC4 status and its changes were analyzed in 156 patients with breast cancer. Associations between pCR, RFS rates to IHC4 status pre- and post-NACT were investigated. RESULTS: pCR was found in 25.3% patients. Both ER and PR positive tumors had the lowest (14.3%) pCR compared to ER and PR negative (29%) or either ER-/PR-positive (38.6%) tumors. PR positivity was significantly associated with less likelihood of pCR (15% versus 34%). The pCR rate was low for luminal A subtype (13.68%) compared to 24.36%, 26.31%, and 33.33% for luminal B, HER2-enriched, and triple-negative subtypes, respectively. There was significant reduction in ER expression and Ki-67 index post-NACT. RFS of patients in whom the hormonal status changed from positive to negative was better compared to those of patients in whom the hormonal status changed from negative to positive. CONCLUSION: Although changes in IHC4 occurred post-NACT, pre-NACT hazard ratio status prognosticated RFS better. pCR and RFS rates were lower in PR-positive tumors.

"Score the Core" Web-based pathologist training tool improves the accuracy of breast cancer IHC4 scoring.

Hormone receptor status is an integral component of decision-making in breast cancer management. IHC4 score is an algorithm that combines hormone receptor, HER2, and Ki-67 status to provide a semiquantitative prognostic score for breast cancer. High accuracy and low interobserver variance are important to ensure the score is accurately calculated; however, few previous efforts have been made to measure or decrease interobserver variance. We developed a Web-based training tool, called "Score the Core" (STC) using tissue microarrays to train pathologists to visually score estrogen receptor (using the 300-point H score), progesterone receptor (percent positive), and Ki-67 (percent positive). STC used a reference score calculated from a reproducible manual counting method. Pathologists in the Athena Breast Health Network and pathology residents at associated institutions completed the exercise. By using STC, pathologists improved their estrogen receptor H score and progesterone receptor and Ki-67 proportion assessment and demonstrated a good correlation between pathologist and reference scores. In addition, we collected information about pathologist performance that allowed us to compare individual pathologists and measures of agreement. Pathologists' assessment of the proportion of positive cells was closer to the reference than their assessment of the relative intensity of positive cells. Careful training and assessment should be used to ensure the accuracy of breast biomarkers. This is particularly important as breast cancer diagnostics become increasingly quantitative and reproducible. Our training tool is a novel approach for pathologist training that can serve as an important component of ongoing quality assessment and can improve the accuracy of breast cancer prognostic biomarkers.

Score ihc 4 + c y riesgo de recurrencia en pacientes con cáncer de mama / Score ihc 4 + c and Risk of Recurrence (rr) in breast cancer

Introducción Las plataformas genéticas estiman el riesgo de recurrencia (rr) en cáncer de mama. La más utilizada es Oncotype DX. Una herramienta de bajo costo es ihc 4 + c que proporciona información pronóstica sobre el rr a distancia similar a Oncotype DX®. Objetivo Evaluar riesgo de recurrencia local y a distancia según ihc 4 + c. Material y método La población accesible estuvo constituida por 61 historias clínicas de pacientes con cáncer de mama con receptores hormonales positivos, a las que se le aplicó el score y se evalúo rr. Resultados El 64% de las pacientes tuvieron bajo rr. 7 pacientes (12%) presentó recidiva. De las pacientes del grupo que recibió quimioterapia (Q1), 5 (31%) tenían alto rr según ihc 4 + c. Del grupo que no recibió quimioterapia (Q2), solo 6 (13%) presentaban alto rr (p= 0,08). De las pacientes con bajo riesgo según ihc 4 + c, solo 1 (3%) tuvo recidiva (p=0,015). Conclusiones En este trabajo se encontró asociación estadísticamente significativa entre rr por ihc 4 + c y tasa de recurrencia. El ihc 4 + c podría ayudar en la toma de decisiones en aquellas pacientes en las cuales no está claro si se beneficiarán con el uso de la quimioterapia

Introduction Genetic platforms estimate the risk of recurrence (rr) in breast cancer. The most used is Oncotype DX. A low-cost tool is ihc 4 + c that provides prognostic information about rr remotely similar to Oncotype DX®. Objective To evaluate the risk of local and distant recurrence according to ihc 4 + c. Materials and method The accessible population consisted of 61 clinical histories of patients with breast cancer with positive hormone receptors, to whom the score was applied and rr was evaluated. Results 64% of the patients had low rr. 7 (12%) had recurrence. The group who receiving chemotherapy (Q1), 5 (31%) had high rr according to ihc 4 + c. The group that did not receive chemotherapy (Q2), only 6 (13%) had high rr p = 0.08. The patients with low risk according to ihc 4 + c, only 1 (3%) had recurrence (p = 0.015). Conclusions This study found a statistically significant association between rr by ihc 4 + c and recurrence rate. The ihc 4 + c could help in decision-making in those patients in whom it is not clear if they will benefit from the use of chemotherapy