Effect of Ki-67 assessment in the distribution of breast cancer subtypes: Evaluation in a cohort of Latin American patients

Intercontinental Comparison of Immunohistochemical Subtypes Among Individuals With Breast Cancer in South-East Asia and South America: A Scoping Systematic Review and Meta-Analysis of Observational Studies

Background

Breast cancer (BC) remains a significant global concern, particularly among developing countries in South-East Asia (SEA) and South America (SA). The socioeconomic burdens of oncologic care in those countries were often originated from limited accessibility on attainable therapeutic options and reliability on identifying essential information of cancer cells, i.e., immunohistochemical (IHC) subtyping to determine suitable approaches. The triple-negative breast cancer (TNBC) is among the most aggressive category in breast malignancy, therefore, requiring more specific molecular pathway blocking to exhaust the cells. However, large-scale epidemiological investigation on its rate among BC remains unavailable to date. This study aimed to describe the prevalence of TNBC in the SEA and SA continents since it may guide the future direction of oncologic research and trials.

Methods

This review focuses on observational studies from the SEA and SA continents from the last decade. Each study represents its country or cities, period of observation, population size, and the TNBC-BC rate as the main outcomes. Therefore, we may also limit the reporting bias originated from same-patient data on the specific occasions. The analysis will be derived to SEA-SA comparison, plus SEA/SA-specific session as processed in Comprehensive Meta-Analysis (CMA) version 3.0. The statistical analysis will be performed in random effects model (REM) within 95% confidence interval (CI).

Results

From 46 studies included in the final analysis with a total enlisted population of 34,346 unique individuals with BC, the TNBC rate was higher in the SEA compared to the SA region (19.3% vs. 15.7%; P < 0.05 in 95% CI), with the highest prevalence observed in Vietnam (22.4%) and Peru (17.8%), if it was restricted on countries with two or more studies. Interestingly, both Laos and Argentina possessed significant differences compared to other countries within their respective continents, with the highest and lowest TNBC rates (P < 0.05).

Conclusions

The IHC characteristics in SEA differ from those in the SA continent as mainly represented by TNBC prevalence, possibly shaping the course of future trials in the respective region based on IHC expressivity status.

Analysis on status quo and related factors of delays in diagnosis and treatment of breast cancer in Ningxia Hui Autonomous Region

This study aimed to explore factors contributing to the delays in the diagnosis and treatment of breast cancer (BC) in Ningxia Hui Autonomous Region. We conducted a cohort analysis of 1012 patients with BC diagnosed at the General Hospital of Ningxia Medical University between January 2018 and December 2019. Sociodemographic data were collected through questionnaires, and clinical data were gathered and analyzed from relevant databases. Furthermore, observations were made regarding delays in the diagnosis and treatment of BC, followed by an analysis of the correlations between patient delay and both sociological factors within the population and clinical factors specific to patients with BC. Subsequently, the factors associated with patient delay and system delay were examined using Cox regression analysis, along with the inclusion of neoadjuvant therapy. In the prevention and treatment of BC in Ningxia, the patient delay rate was 33.20%, the diagnosis delay rate was 17.89%, the treatment delay rate was 0.0099% and the system delay rate was 41.60%. There was a higher proportion of patient delay and system delay in aged patients (age ≥ 61 years) with rural registered permanent residence (RPR), multiple clinical symptoms (such as nipple spillage, axillary abnormalities, etc), a T4 tumor size classification, and the initial use of neoadjuvant therapy. Besides, significant positive correlations were observed between patient delay and system delay time with BC stage. Patients aged 51 to 60 and those with molecular types (Limanal1B: ki-67 > 14%, Limanal1B: HER-2 positive) were prone to patient delay, whereas molecular characteristics influenced system delay, unrelated to sociodemographic factors. The study identifies significant age, residency, and tumor molecular subtype correlations with diagnostic and treatment delays in Ningxia's patients with BC, predominantly affecting women aged 41 to 60, especially urban dwellers. These findings underscore the need for targeted interventions to reduce delays and improve BC care in this region.

Breast cancer subtype and clinical characteristics in women from Peru

Introduction

Breast cancer is a heterogeneous disease, and the distribution of the different subtypes varies by race/ethnic category in the United States and by country. Established breast cancer-associated factors impact subtype-specific risk; however, these included limited or no representation of Latin American diversity. To address this gap in knowledge, we report a description of demographic, reproductive, and lifestyle breast cancer-associated factors by age at diagnosis and disease subtype for The Peruvian Genetics and Genomics of Breast Cancer (PEGEN-BC) study.

Methods

The PEGEN-BC study is a hospital-based breast cancer cohort that includes 1943 patients diagnosed at the Instituto Nacional de Enfermedades Neoplásicas in Lima, Peru. Demographic and reproductive information, as well as lifestyle exposures, were collected with a questionnaire. Clinical data, including tumor Hormone Receptor (HR) status and Human Epidermal Growth Factor Receptor 2 (HER2) status, were abstracted from electronic medical records. Differences in proportions and mean values were tested using Chi-squared and one-way ANOVA tests, respectively. Multinomial logistic regression models were used for multivariate association analyses.

Results

The distribution of subtypes was 52% HR+HER2-, 19% HR+HER2+, 16% HR-HER2-, and 13% HR-HER2+. Indigenous American (IA) genetic ancestry was higher, and height was lower among individuals with the HR-HER2+ subtype (80% IA vs. 76% overall, p=0.007; 152 cm vs. 153 cm overall, p=0.032, respectively). In multivariate models, IA ancestry was associated with HR-HER2+ subtype (OR=1.38,95%CI=1.06-1.79, p=0.017) and parous women showed increased risk for HR-HER2+ (OR=2.7,95%CI=1.5-4.8, p<0.001) and HR-HER2- tumors (OR=2.4,95%CI=1.5-4.0, p<0.001) compared to nulliparous women. Multiple patient and tumor characteristics differed by age at diagnosis (<50 vs. >=50), including ancestry, region of residence, family history, height, BMI, breastfeeding, parity, and stage at diagnosis (p<0.02 for all variables).

Discussion

The characteristics of the PEGEN-BC study participants do not suggest heterogeneity by tumor subtype except for IA genetic ancestry proportion, which has been previously reported. Differences by age at diagnosis were apparent and concordant with what is known about pre- and post-menopausal-specific disease risk factors. Additional studies in Peru should be developed to further understand the main contributors to the specific age of onset and molecular disease subtypes in this population and develop population-appropriate predictive models for prevention.

Neoadjuvant pertuzumab in non‑metastatic HER2‑positive breast tumors: Multicentric study in Peru (NeoHer)

Several clinical trials have demonstrated the benefit of adding pertuzumab to trastuzumab plus neoadjuvant chemotherapy in the treatment of human epidermal growth factor receptor 2 (HER2)-positive breast cancer. The comparison of outcomes between nonrandomized groups of patients who received similar treatments in routine practice remains difficult. The present study aimed to evaluate the pathological complete response (pCR) rates achieved with pertuzumab among patients in routine clinical care in Peru using real-world data. The definition of pCR used was the absence of residual invasive cancer from the complete resected breast specimen and all sampled regional lymph nodes following completion of neoadjuvant systemic therapy. A total of 44 patients with non-metastatic HER2-positive breast cancer (stages II and III) treated with pertuzumab in the neoadjuvant setting and who underwent surgery at three private clinics in Lima (Peru) were retrospectively evaluated. The pCR was the efficacy endpoint and it was determined and compared with the results from other clinical trials. Furthermore, safety data were described. The median age was 44 years (interquartile range, 39.5-50.5 years) and 65.9% of patients were premenopausal. Regarding the clinical stage, 56.8% were IIA/IIB and 36.4% were IIIA/IIIB/IIIC. All treatment schemes included concurrent trastuzumab. The patients' treatment comprised neoadjuvant therapy of docetaxel/trastuzumab/pertuzumab (THP) with a median of 4 cycles in 30 patients (68.2%) or docetaxel/trastuzumab/pertuzumab/carboplatin (THPCarb) with a median of 6 cycles in 14 patients (31.8%). In total, 70.5% of patients experienced pCR; among hormone receptor-negative cases, 75.0% achieved pCR and in tumors expressing hormone receptors, the rate of pCR was 66.7%. Of those patients subjected to neoadjuvant treatment with THP, 66.7% (20/30) achieved pCR, whereas 78.6% (11/14) of patients who received THPCarb had a pCR. The incidence of drug-related adverse events was 59.1% and in none of the patients, administration was discontinued due to toxicity. The present results of Peruvian patients with HER2 breast cancer treated according to clinical routine demonstrated that dual blockade of HER2 with trastuzumab and pertuzumab in the neoadjuvant setting achieved high rates of pCR even in hormone receptor-positive patients. These results are consistent with those of randomized controlled trials, with a good safety profile.

Impact of the Delayed Initiation of Adjuvant Chemotherapy in the Outcome of Triple Negative Breast Cancer

BACKGROUND

Adjuvant chemotherapy decreases the recurrence risk and improves survival rates; however, it is unclear whether a delayed initiation is associated with adverse outcomes, especially in triple negative breast cancer (TNBC). In this study, we evaluated the influence of the time to start adjuvant chemotherapy (TTC) in the outcomes of TNBC.

PATIENTS AND METHODS

We retrospectively analyzed 15 years of data from patients with TNBC who received adjuvant chemotherapy at the Instituto Nacional de Enfermedades Neoplasicas (Lima, Peru). TTC was categorized into 4 groups: ≤ 30, 31 to 60, 61 to 90, and ≥ 91 days. We evaluated overall survival (OS) and distant recurrence-free survival (DRFS). Cox proportional hazard models were used to identify prognostic factors.

RESULTS

In total, 687 patients were included. The mean age at diagnosis was 49.1 years (SD, 11.8 years), and most (62.6%) patients had pathologic stage T2. The median TTC was 48.1 days (SD, 27.4 days); 189 (27.5%) received chemotherapy ≤ 30 days; 329 (47.9%), between 31 and 60 days; 115 (16.7%), between 61 and 90 days; and 54 (7.9%) in ≥ 90 days. In the multivariate analysis, a TTC between 31 and 60 days (hazard ratio [HR], 1.78; 95% confidence interval [CI], 1.17-2.72), 61 and 90 days (HR, 2.38; 95%CI, 1.43-3.97), and ≥ 91 days (HR, 2.45; 95% CI, 1.32-4.55) was associated with an increased mortality in contrast with a TTC < 30 days. Although a TTC between 31 and 60 days, 61 and 90 days, and ≥ 91 days was associated with an increased risk of DRFS (HR, 1.86; 95% CI, 1.24-2.79; HR, 2.34, 95% CI, 1.42-3.867; and HR, 3.16; 95% CI, 1.78-5.61, respectively).

CONCLUSION

A delaying in TTC ≥ 30 days was associated with poorer outcomes. Our data suggest that several efforts should be conducted to avoid a delayed TTC in patients with TNBC.

The hispanic landscape of triple negative breast cancer

Triple-negative breast cancer (TNBC) is a heterogeneous and complex disease characterized by the absence of immunohistochemical expression of estrogen receptor, progesterone receptor and HER2. These breast tumors present an aggressive biology and offer few opportunities to be treated with targeted therapy resulting in bad disease outcomes. The epidemiology of TNBC is intriguing where the understanding of its biology has progressed quickly. One of the peculiarities of this type of cancer is a high prevalence in Afrodescendants and Hispanic patients compared to Caucasian women. In this review we describe some features of TNBC, focusing in the Hispanic population, such as epidemiological, clinicopathological features and molecular features and the correlation between TNBC prevalence and the human development index.

Breast-conserving surgery vs. total mastectomy in patients with triple negative breast cancer in early stages: A propensity score analysis

BACKGROUND

Breast-conserving surgery (BCS) as an alternative to total mastectomy (TM) in patients with early-stage triple-negative breast cancer (TNBC) is not widely spread.

OBJECTIVE

We aimed to compare the overall survival (OS) and disease-free survival (DFS) between both surgical approaches in early-stage TNBC patients at 10 years.

METHODS

We conducted a retrospective cohort study in TNBC female patients with stage I-IIa, treated at a single-center during the period of 2000-2014. We estimated and compared the survival rates with the Kaplan Meier and Long-rank test. Propensity scores were calculated with the generalized boosted regression model and were used in the multivariate Cox regression analysis with the covariate adjustment method.

RESULTS

We included 288 patients, 111 in the BCS vs. 177 in the TM group. The median follow-up was 102 months. Moreover, the patients in the BCS group had superior OS (85% vs. 81%, p = 0.56) and DFS (83% vs. 80%, p = 0.42) at 10 years. In the multivariate Cox analysis, BCS decreased the mortality risk (HR: 0.79, 95% CI: 0.37-1.67, p = 0.538), and the locoregional or distant recurrence risk (HR: 0.67, 95% CI: 0.32-1.41, p = 0.294), albeit with no statistical significance.

CONCLUSION

BCS is a safe alternative to TM in Latin-American patients with early-stage TNBC.

Precision medicine for locally advanced breast cancer: frontiers and challenges in Latin America

Advances in high-throughput technologies and their involvement in the 'omics' of cancer have made possible the identification of hundreds of biomarkers and the development of predictive and prognostic platforms that model the management of cancer from evidence-based medicine to precision medicine. Latin America (LATAM) is a region characterised by fragmented healthcare, high rates of poverty and disparities to access to a basic standard of care not only for cancer but also for other complex diseases. Patients from the public setting cannot afford targeted therapy, the facilities offering genomic platforms are scarce and the use of high-precision radiotherapy is limited to few facilities. Despite the fact that LATAM oncologists are well-trained in the use of genomic platforms and constantly participate in genomic projects, a medical practice based in precision oncology is a great challenge and frequently limited to private practice. In breast cancer, we are waiting for the results of large basket trials to incorporate the detection of actionable mutations to select targeted treatments, in a similar way to the management of lung cancer. On the other hand and paradoxically, in the 'one fit is not for all' era, clinical and genomic studies continue grouping our patients under the single label 'Latin American' or 'Hispanic' despite the different ancestries and genomic backgrounds seen in the region. More regional cancer genomic initiatives and public availability of this data are needed in order to develop more precise oncology in locally advanced breast cancer.

Barriers in Latin America for the management of locally advanced breast cancer

Breast cancer (BC) is a highly prevalent malignancy in Latin American women, most cases being diagnosed at locally advanced or metastatic stages when options for cancer care are limited. Despite its label as a public health problem in the region, Latin American BC patients face several barriers in accessing standard of care treatment when compared with patients from developed countries. In this review, we analyse the landscape of the four main identified barriers in the region: i) high burden of locally advanced/advanced BC; ii) inadequate access to medical resources; iii) deficient access to specialised cancer care and iv) insufficient BC research in Latin America. Unfortunately, these barriers represent the main factors associated with the BC poor outcomes seen in the region. Targeted actions should be conducted independently by each country and as a region to overcome these limitations and create an enhanced model of BC care.

Cell biology of glioblastoma multiforme: from basic science to diagnosis and treatment

First described in the 1800s, glioblastoma multiforme (GBM), a class IV neoplasm with astrocytic differentiation, as per the revised 2016 World Health Organization classification of tumors of the central nervous system (CNS) is the most common malignant tumor of the CNS. GBM has an extremely wide set of alterations, both genetic and epigenetic, which yield a great number of mutation subgroups, some of which have an established role in independent patient survival and treatment response. All of those components not only represent a closed cycle but are also relevant to the tumor biological behavior and resistance to treatment as they form the pathobiological behavior and clinical course. The presence of different triggering mutations on the background of the presence of key mutations in the GBM stem cells (GBMsc) further separates GBM as primary arising de novo from neural stem cell precursors developing into GBMsc and secondary, by means of aggregated mutations. Some of the change in cellular biology in GBM can be observed via light microscope as they form the cellular and tissue hallmarks of the condition. Changes in genetic information, resulting in alteration, suppression and expression of genes compared to their physiological levels in healthy astrocytes lead to not only cellular, but also extracellular matrix reorganization. These changes result in a multiform number of micromorphological and purely immunological/biochemical forms. Therefore, in the twenty-first century the term multiforme, previously outcast from nomenclatures, has gained new popularity on the background of genotypic diversity in this neoplastic entry.

Correlation Between Ki-67 Index, World Health Organization Grade and Patient Survival in Glial Tumors With Astrocytic Differentiation

Background

Glioblastoma multiforme (GBM) is a class IV astrocytic tumor, the most malignant of the four groups of World Health Organization (WHO) tumors with astrocytic differentiation.

Aim

The aim of this study was to estab­lish whether a correlation exists between the Ki-67 index of tumors with astrocytic differentiation, WHO grade, and patient survival.

Materials and methods

A retrospective non-clinical approach to patient selection was chosen for the aim of the study. A total of 47 patients diagnosed and treated for CNS tumors with astrocytic differentiation in the St. Marina University Hospital, Varna, Bulgaria, from September 2012 to July 2016 were retrospectively included into the study cohort. The cases were tested for their immunohistochemistry (IHC) reaction with Ki-67 after their original Hematoxylin and Eosin and IHC slides were reviewed by a single author and blind coded. The Ki-67 positivity index of the nuclei was estimated after digitalization of the slides and calculated by the ImmunoRatio automated count­ing tool. The individual Ki-67 index and patient survival of each case were statistically compared.

Results

The histopathological groups, after the blind Ki-67 index automated calculation was carried out, revealed no WHO grade I, two WHO grade II samples, four WHO grade III samples and 41 WHO grade IV cases, and these were included in the analysis. The two samples of WHO grade II astrocytic tumors had a mean Ki-67 index of 25%; however, they comprised tumors with an individual index of 43% and 7%, both individual values with a highly unlikely index for this group. The four samples of WHO grade III had a mean Ki-67 index of 4%, standard deviation ±2.16 (p>0.05), with the lowest index being 1% and the highest one being 6%. Both WHO grade II and III did not include enough samples to allow for a proper statistical analysis of patient survival. The 41 GBM cases had a mean Ki-67 index of 17.34%, standard deviation ±10.79 (p>0.05). Statistical analysis of the Ki-67 index divid­ed dichotomously into two groups and patient survival revealed that cases with a high Ki-67 index had no significant difference in survival when compared to those with low expression.

Conclusions

Based on the reported results, the mean Ki-67 percentage of positive nuclei in GBM tumor sam­ples cannot be used to estimate the survival of patients. However, Ki-67 remains a valuable IHC pathological tool.