Subcutaneous Trastuzumab: An Observational Study of Safety and Tolerability in Patients With Early HER2-Positive Breast Cancer.

Purpose: In Peru, breast cancer (BC) stands as the most predominant malignancy neoplasm among women. Trastuzumab has marked a significant milestone in the management of this disease. It has been shown to improve prognosis in human epidermal growth factor receptor 2 (HER2)-expressing female patients, but its repercussions and efficacy are yet to be analyzed in a context with limited resources. Methods: The study population is made of woman patients aged 18 years and older diagnosed with HER2-positive BC at Instituto Nacional de Enfermedades Neoplásicas (INEN, Lima, Peru) during 2019-2021 and treated with at least one dose of subcutaneous trastuzumab. We reviewed medical records to register treatment characteristics, adverse events (AEs), disease progression, and survival status. We considered a median follow-up time of 36 and 45 months for progression and survival status. Results: The majority of patients were over 50 years old (54.29%). Tumor size averaged 19.7 ± 16.1 mm. Lymph nodes were present in 44.78% of patients. Most patients received adjuvant chemotherapy (63.8%) as first-line treatment. Descriptive analyses of treatment outcomes revealed a 30% toxicity rate, primarily attributed to arthralgia (47.62%), followed by diarrhea, fatigue, and injection site reactions, with relatively lower discontinuation rates compared to larger scale studies. Differences in demographic, clinical, and treatment characteristics were not statistically significant concerning the emergence of AEs (p > 0.05). Progression appeared in nine patients, and the overall survival (OS) rate stood at 98.6% and 92.8%, respectively, during a median follow-up of 36 and 45 months. Conclusion: The research suggests that subcutaneous trastuzumab is comparable in effectiveness and safety to the intravenous administration. Regional-specific studies may provide valuable insights into demographic factors influencing treatment outcomes in Peru or other countries. Furthermore, it could represent a more accessible alternative, potentially enhancing patient adherence and optimizing healthcare resource logistics.

Subcutaneous versus intravenous administration of Trastuzumab: a minimization cost analysis with real world data from a reference cancer centre in Peru.

Breast cancer (BC) is a global concern, with Peru experiencing a high incidence and mortality. Trastuzumab, a crucial treatment for human epidermal growth factor receptor 2-positive BC, is administered intravenously or subcutaneously (SC). This study evaluates the costs associated with both methods at Peru's Instituto Nacional de Enfermedades Neoplásicas. Real data indicate that SC administration reduces treatment costs by approximately S/15,049.09. Cross-continental comparisons highlight a global trend favouring SC administration for efficiency and cost-effectiveness. The analysis provides insights for informed decision-making in resource-constrained healthcare settings like Peru, emphasising the need to consider local contexts in optimising oncology care.

Boosting self-efficacy and improving practices for smoking prevention and cessation among South American cancer care providers with a web-based algorithm.

BACKGROUND: Digital technologies have positively impacted the availability and usability of clinical algorithms through the advancement in mobile health. Therefore, this study aimed to determine if a web-based algorithm designed to support the decision-making process of cancer care providers (CCPs) differentially impacted their self-reported self-efficacy and practices for providing smoking prevention and cessation services in Peru and Colombia. METHODS: A simple decision-making tree algorithm was built in REDCap using information from an extensive review of the currently available smoking prevention and cessation resources. We employed a pre-post study design with a mixed-methods approach among 53 CCPs in Peru and Colombia for pilot-testing the web-based algorithm during a 3-month period. Wilcoxon signed-rank test was used to compare the CCPs' self-efficacy and practices before and after using the web-based algorithm. The usability of the web-based algorithm was quantitatively measured with the system usability scale (SUS), as well as qualitatively through the analysis of four focus groups conducted among the participating CCPs. RESULTS: The pre-post assessments indicated that the CCPs significantly improved their self-efficacy and practices toward smoking prevention and cessation services after using the web-based algorithm. The overall average SUS score obtained among study participants was 82.9 (± 9.33) [Peru 81.5; Colombia 84.1]. After completing the qualitative analysis of the focus groups transcripts, four themes emerged: limited resources currently available for smoking prevention and cessation in oncology settings, merits of the web-based algorithm, challenges with the web-based algorithm, and suggestions for improving this web-based decision-making tool. CONCLUSION: The web-based algorithm showed high usability and was well-received by the CCPs in Colombia and Peru, promoting a preliminary improvement in their smoking prevention and cessation self-efficacy and practices.

Choosing Wisely in oncology in Latin America: what SLACOM does not recommend in the care of cancer patients in Latin America: Ten essential recommendations to avoid harmful onclogy procedures in Latin America.

Choosing Wisely is an initiative by the American Board of Internal Medicine (ABIM) and ABIM Foundation to deter unnecessary medical treatments and procedures. Faced with the burden of modern technologies and treatments, it is crucial to identify practices lacking value in daily care. The Latin American and Caribbean Society (SLACOM), comprising cancer control experts, deems it vital to tailor this initiative for enhancing cancer care in the region. Through a modified DELPHI methodology involving two rounds of electronic questionnaires and a hybrid meeting to discuss key points of contention, ten essential recommendations were identified and prioritised to avoid harmful oncology procedures in our region. These consensus-based recommendations, contextualised for Latin America, have been compiled and shared to benefit patients. The Scientific Committee, consisting of prominent oncologists and health experts, collaborates remotely to drive this project forward.

Subpopulation treatment effect pattern plot analysis: a prognostic model for distant recurrence-free survival to estimate delayed adjuvant chemotherapy initiation effect in triple-negative breast cancer.

Introduction: Triple-negative breast cancer (TNBC) is a heterogeneous disease associated with a poor prognosis. Delaying in time to start adjuvant chemotherapy (TTC) has been related to an increased risk of distant recurrence-free survival (DRFS). We aimed to develop a prognostic model to estimate the effects of delayed TTC among TNBC risk subgroups. Materials and methods: We analyzed 687 TNBC patients who received adjuvant chemotherapy at the Instituto Nacional de Enfermedades Neoplasicas (Lima, Peru). Database was randomly divided to create a discovery set (n=344) and a validation set (n=343). Univariate and multivariate Cox regression models were performed to identify prognostic factors for DRFS. Risk stratification was implemented through two models developed based on proportional hazard ratios from significant clinicopathological characteristics. Subpopulation treatment effect pattern plot (STEPP) analysis was performed to determine the best prognostic cut-off points for stratifying TNBC subgroups according to risk scores and estimate Kaplan-Meier differences in 10-year DRFS comparing TTC (≤30 vs.>30 days). Results: In univariate analysis, patients aged ≥70 years (HR=4.65; 95% CI: 2.32-9.34; p=<0.001), those at stages pT3-T4 (HR=3.28; 95% CI: 1.57-6.83; p=0.002), and pN2-N3 (HR=3.00; 95% CI: 1.90-4.76; p=<0.001) were notably associated with higher risk. STEPP analysis defined three risk subgroups for each model. Model N°01 categorized patients into low (score: 0-31), intermediate (score:32-64), and high-risk (score: 65-100) cohorts; meanwhile, Model N°02: low (score: 0-26), intermediate (score: 27-55), and high (score: 56-100). Kaplan-Meier plots showed that in the discovery set, patients with TTC>30 days experienced a 17.5% decrease in 10-year DRFS rate (95%CI=6.7-28.3), and the impact was more remarkable in patients who belong to the high-risk subgroup (53.3% decrease in 10 years-DRFS rate). Similar results were found in the validation set. Conclusions: We developed two prognostic models based on age, pT, and pN to select the best one to classify TNBC. For Model N°02, delayed adjuvant chemotherapy conferred a higher risk of relapse in patients ≥70 years and who were characterized by pT3/T4 and pN2/N3. Thus, more efforts should be considered to avoid delayed TTC in TNBC patients, especially those in high-risk subgroups.

Temporal Variation of Treatment Patterns and Survival Outcomes of Triple-Negative Breast Cancer Patients: A Real-World Experience From 2000 to 2014.

BACKGROUND: Previous studies have reported a higher prevalence of triple-negative breast cancer (TNBC) in US Hispanic/Latina populations. However, survival outcomes and treatment approaches over time in Latin American females are scarcely reported. We aimed to evaluate the temporal variation in treatment patterns and overall survival (OS) outcomes of females with TNBC according to cancer stage. MATERIALS AND METHODS: We performed a single-center retrospective cohort study on 1840 females from 2000 to 2014. Patients were classified in 3 calendar periods (2000-2004, 2005-2009, and 2010-2014). The Kaplan-Meier method and multivariable regression analyses were employed. RESULTS: Stage III cancer was identified in half of the population. Five-year OS estimates for cancer stages I, II, and IV remained unchanged across all calendar periods. However, we found worsening 5-year OS estimates in stage III females (49% in 2000-2004 and 31% in 2010-2014; P < .001). Despite increased uptake of overall use of neoadjuvant therapy in stage III females, the time from diagnosis to treatment initiation (P = .013) and time to complete the planned cycles (P < .001) increased over time. Fifty-sex percent of stage IV patients were untreated. Females aged ≥70 years were less likely to receive treatment. CONCLUSIONS: Survival estimates were lower than those reported in high-income countries. Most females were diagnosed with advanced disease, and the OS for stage III females worsened over time. Our outcomes show difficulties in delivering timely neoadjuvant therapy in an overwhelmed healthcare system. Public health authorities should improve screening practices, develop regional clinical guidelines, and expand trial enrollment.

The STOP Program: a Hybrid Smoking Prevention and Cessation Training for Cancer Care Providers in Colombia and Peru.

We designed and tested the feasibility of the Smoking Cessation Training Program for Oncology Practice (STOP), a hybrid (face-to-face plus web-based) educational intervention to enhance Spanish-speaking cancer care professionals' (CCPs') ability to provide brief smoking prevention and cessation counseling to cancer patients and survivors. Changes in the CCPs' competencies (knowledge, attitude, self-efficacy, and practices toward smoking and smoking cessation services) were assessed post-training. Sixty CCPs from one major cancer center in Colombia (n = 30) and Peru (n = 30) were invited to participate in a 4-module hybrid training program on smoking prevention and cessation. Demographic and pre- and post-test evaluation data were collected. The training's acceptability was measured after each module. Bivariate analysis was conducted using Wilcoxon signed-rank test to compare the CCPs' competencies before and after the delivery of the STOP Program. Effect sizes were computed over time to assess the sustainability of the acquired competencies. Twenty-nine CCPs in Colombia and 24 CCPs in Peru completed the STOP Program (96.6% and 80.0% retention rates, respectively). In both countries, 98.2% of the CCPs reported that the overall structure and organization of the program provided an excellent learning experience. The pre-post-test evaluations indicated that the CCPs significantly improved their knowledge, attitude, self-efficacy, and practices toward smoking, smoking prevention, and cessation services. We found that the CCPs' self-efficacy and practices increased over time (1-, 3-, and 6-month assessments after completing the 4 educational modules). The STOP Program was effective and well-received, demonstrating remarkable changes in CCPs' competencies in providing smoking prevention and cessation services to cancer patients.

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.

Knowledge, attitudes, and behaviors toward fertility preservation in patients with breast cancer: A cross-sectional survey of physicians.

Background: Fertility is an important issue for young women with breast cancer, but studies about physicians' knowledge, attitudes, and practices toward fertility preservation (FP) are largely based on Western populations and do not reflect recent international guidelines for FP. In this international study, we aimed to assess the knowledge, attitudes, and practices of physicians from South Korea, other Asian countries, and Latin America toward FP in young women with breast cancer, and identify the related barriers. Methods: The survey was conducted anonymously among physicians from South Korea, other Asian countries, and Latin America involved in breast cancer care between November 2020 and July 2021. Topics included knowledge, attitudes, and perceptions toward FP; practice behaviors; barriers; and participant demographics. We grouped related questions around two main themes-discussion with patients about FP, and consultation and referral to a reproductive endocrinologist. We analyzed the relationships between main questions and other survey items. Results: A total of 151 physicians completed the survey. Most participants' overall knowledge about FP was good. More than half of the participants answered that they discussed FP with their patients in most cases, but that personnel to facilitate discussions about FP and the provision of educational materials were limited. A major barrier was time constraints in the clinic (52.6%). Discussion, consultations, and referrals were more likely to be performed by surgeons who primarily treated patients with operable breast cancer (FP discussion odds ratio [OR]: 2.90; 95% confidence interval [CI]: 1.24-6.79; FP consultation and referral OR: 2.98; 95% CI: 1.14-7.74). Participants' knowledge and attitudes about FP were significantly associated with discussion, consultations, and referrals. Conclusion: Physicians from South Korea, other Asian countries, and Latin America are knowledgeable about FP and most perform practice behaviors toward FP well. Physicians' knowledge and favorable attitudes are significantly related to discussion with patients, as well as consultation with and referral to reproductive endocrinologists. However, there are also barriers, such as limitations to human resources and materials, suggesting a need for a systematic approach to improve FP for young women with breast cancer.

The impact of telemedicine on cancer care: real-world experience from a Peruvian institute during the COVID-19 pandemic.

Background: The COVID-19 pandemic caused discontinuities in cancer care (CC) in most countries. Here, the authors describe the real-world impacts of implementing a contingency plan employing telemedicine for CC. Methods: A retrospective study of patients who received CC through telemedicine at the Instituto Nacional de Enfermedades Neoplasicas, Peru, from March 2020 to February 2021 was conducted. Impacts were measured by comparing the amount of CC administered during the pandemic versus the prior year. Results: A total of 16,456 telemedicine visits were carried out. An annual comparative analysis showed a gap of 23% and telemedicine accounted for 27.6% of the total CC administered during the pandemic. A high (4.50/5) level of patient satisfaction with telemedicine was reported. Conclusion: Telemedicine is an important tool to facilitate the continuity of CC.

Uncovering Signals of Positive Selection in Peruvian Populations from Three Ecological Regions.

Peru hosts extremely diverse ecosystems which can be broadly classified into the following three major ecoregions: the Pacific desert coast, the Andean highlands, and the Amazon rainforest. Since its initial peopling approximately 12,000 years ago, the populations inhabiting such ecoregions might have differentially adapted to their contrasting environmental pressures. Previous studies have described several candidate genes underlying adaptation to hypobaric hypoxia among Andean highlanders. However, the adaptive genetic diversity of coastal and rainforest populations has been less studied. Here, we gathered genome-wide single-nucleotide polymorphism-array data from 286 Peruvians living across the three ecoregions and analyzed signals of recent positive selection through population differentiation and haplotype-based selection scans. Among highland populations, we identify candidate genes related to cardiovascular function (TLL1, DUSP27, TBX5, PLXNA4, SGCD), to the Hypoxia-Inducible Factor pathway (TGFA, APIP), to skin pigmentation (MITF), as well as to glucose (GLIS3) and glycogen metabolism (PPP1R3C, GANC). In contrast, most signatures of adaptation in coastal and rainforest populations comprise candidate genes related to the immune system (including SIGLEC8, TRIM21, CD44, and ICAM1 in the coast; CBLB and PRDM1 in the rainforest; and BRD2, HLA-DOA, HLA-DPA1 regions in both), possibly as a result of strong pathogen-driven selection. This study identifies candidate genes related to human adaptation to the diverse environments of South America.

Association between Ancestry-Specific 6q25 Variants and Breast Cancer Subtypes in Peruvian Women.

BACKGROUND: Breast cancer incidence in the United States is lower in Hispanic/Latina (H/L) compared with African American/Black or Non-Hispanic White women. An Indigenous American breast cancer-protective germline variant (rs140068132) has been reported near the estrogen receptor 1 gene. This study tests the association of rs140068132 and other polymorphisms in the 6q25 region with subtype-specific breast cancer risk in H/Ls of high Indigenous American ancestry. METHODS: Genotypes were obtained for 5,094 Peruvian women with (1,755) and without (3,337) breast cancer. Associations between genotype and overall and subtype-specific risk for the protective variant were tested using logistic regression models and conditional analyses, including other risk-associated polymorphisms in the region. RESULTS: We replicated the reported association between rs140068132 and breast cancer risk overall [odds ratio (OR), 0.53; 95% confidence interval (CI), 0.47-0.59], as well as the lower odds of developing hormone receptor negative (HR-) versus HR+ disease (OR, 0.77; 95% CI, 0.61-0.97). Models, including HER2, showed further heterogeneity with reduced odds for HR+HER2+ (OR, 0.68; 95% CI, 0.51-0.92), HR-HER2+ (OR, 0.63; 95% CI, 0.44-0.90) and HR-HER2- (OR, 0.77; 95% CI, 0.56-1.05) compared with HR+HER2-. Inclusion of other risk-associated variants did not change these observations. CONCLUSIONS: The rs140068132 polymorphism is associated with decreased risk of breast cancer in Peruvians and is more protective against HR- and HER2+ diseases independently of other breast cancer-associated variants in the 6q25 region. IMPACT: These results could inform functional analyses to understand the mechanism by which rs140068132-G reduces risk of breast cancer development in a subtype-specific manner. They also illustrate the importance of including diverse individuals in genetic studies.

Immunotherapy in triple-negative breast cancer: A literature review and new advances.

Triple-negative breast cancer (TNBC) is a highly complex, heterogeneous disease and historically has limited treatment options. It has a high probability of disease recurrence and rapid disease progression despite adequate systemic treatment. Immunotherapy has emerged as an important alternative in the management of this malignancy, showing an impact on progression-free survival and overall survival in selected populations. In this review we focused on immunotherapy and its current relevance in the management of TNBC, including various scenarios (metastatic and early -neoadjuvant, adjuvant-), new advances in this subtype and the research of potential predictive biomarkers of response to treatment.

Cyclophosphamide, Thalidomide, and Dexamethasone as Initial Therapy for Patients With Newly Diagnosed Multiple Myeloma in a Middle-Income Country: 7-Year Follow-Up.

PURPOSE: Major progress has occurred in multiple myeloma (MM) treatment in recent years, but this is not seen in low- and middle-income countries. MATERIALS AND METHODS: We retrospectively assessed the efficacy and safety of cyclophosphamide, thalidomide, and dexamethasone (cyclophosphamide 400 mg/m2 for 5 days, thalidomide 100 mg once daily, if tolerated, and dexamethasone 40 mg once weekly; in 28-day cycles) in patients with newly diagnosed MM treated at our institution between April 2008 and December 2012. Survival outcomes were estimated by the Kaplan-Meier method. RESULTS: Fifty-nine patients were found to meet the selection criteria. Median age was 56 years (27-78). Fifty-nine percent (n = 35) were male. International Staging System three was found in 24%. The median number of treatment cycles was 11 (range 4-12). After a median of 81-month follow-up (range 5-138 months), the overall response rate was 69.5%. The complete response and very good partial response were 5% and 32%, respectively. Median progression-free survival (PFS) was 35 months (95% CI, 18 to 41). The 3-year PFS was 47.4% (95% CI, 34.5 to 59.6) and 5-year PFS was 24.9% (95% CI, 14.4 to 36.9). The median of overall survival (OS) was 81 months (95% CI, 33 to not reached). The 3-year OS was 63.4% (95% CI, 49.2 to 74.6), and 5-year OS was 57.5% (95% CI, 43.2 to 69.4). The most common adverse event was neutropenia (grade 3 and 4, 30.5%). Out of 23 patients eligible for stem-cell transplantation, 10 (43.5%) proceeded with autologous transplantation. Treatment-related deaths occurred in four patients (6.7%). CONCLUSION: Cyclophosphamide, thalidomide, and dexamethasone achieves good response rates with tolerable toxicity, especially in patients age 65 years or younger representing a feasible approach for patients with MM in low-income health care settings.

Depression in women with a diagnosis of breast cancer. Prevalence of symptoms of depression in Peruvian women with early breast cancer and related sociodemographic factors.

We sought to review literature on the prevalence of symptoms of depression in women with a diagnosis of breast cancer (BC) and in the Peruvian population determine the prevalence of symptoms of depression and to describe the association with sociodemographic characteristics. Descriptive cross-sectional analytical study of 254 patients from the National Cancer Institute of Peru (Instituto Nacional de Enfermedades Neoplásicas) with a diagnosis of clinical stage I or II BC. The patients included women aged between 26 and 67 years old. Symptoms of depression were monitored by the Beck Depression Inventory-II. Moreover, clinical features and patient sociodemographic characteristics were analyzed and their association with depression was assessed by logistic regression. The average age of the patients was 47.8 ± 9.2 years; 5.4% of the patients were postmenopausal at the time of the questionnaire. About 55% of women were from Lima, 58.3% had completed secondary education (11 ± 3.2 years), 45.7% were not working, and 46.5% were single. The prevalence of depression was 25.6% at the time of BC diagnosis. Of those patients with symptoms of depression, 16.9% showed symptoms of mild depression, 6.3% moderate, and 2.4% severe. A multivariable logistic regression model showed that in Peruvian women with a diagnosis of BC being married or employed significantly decreased the odds of presenting depressive symptoms (P = 0.029 and 0.017, respectively). Our main limitation was the lack of evaluation of depressive symptoms before the diagnosis, during or at the end of treatment. Another limitation was that the Beck Depression Inventory-II test could only identify depressive symptoms, but not depression as a disease. We have reviewed relevant literature on depression in women with a diagnosis of BC. The data presented suggests an association between both employment and marital status with depressive symptoms among Peruvian women with a diagnosis of BC. Pre-emptive support for women at risk could influence resilience and/or motivation for compliance with antineoplastic treatments.

Human Epidermal Growth Factor Receptor 2-Positive Breast Cancer Is Associated with Indigenous American Ancestry in Latin American Women.

Women of Latin American origin in the United States are more likely to be diagnosed with advanced breast cancer and have a higher risk of mortality than non-Hispanic White women. Studies in U.S. Latinas and Latin American women have reported a high incidence of HER2 positive (+) tumors; however, the factors contributing to this observation are unknown. Genome-wide genotype data for 1,312 patients from the Peruvian Genetics and Genomics of Breast Cancer Study (PEGEN-BC) were used to estimate genetic ancestry. We tested the association between HER2 status and genetic ancestry using logistic and multinomial logistic regression models. Findings were replicated in 616 samples from Mexico and Colombia. Average Indigenous American (IA) ancestry differed by subtype. In multivariate models, the odds of having an HER2+ tumor increased by a factor of 1.20 with every 10% increase in IA ancestry proportion (95% CI, 1.07-1.35; P = 0.001). The association between HER2 status and IA ancestry was independently replicated in samples from Mexico and Colombia. Results suggest that the high prevalence of HER2+ tumors in Latinas could be due in part to the presence of population-specific genetic variant(s) affecting HER2 expression in breast cancer. SIGNIFICANCE: The positive association between Indigenous American genetic ancestry and HER2+ breast cancer suggests that the high incidence of HER2+ subtypes in Latinas might be due to population and subtype-specific genetic risk variants.

Level of tumor-infiltrating lymphocytes and density of infiltrating immune cells in different malignancies.

Aim: To correlate levels of tumor-infiltrating lymphocytes (TIL) evaluated using the International Immuno-Oncology Biomarker Working Group methodology, and both density of tumor-infiltrating immune cell and clinicopathological features in different malignancies. Methods: 209 pathological samples from gastric cancer, cervical cancer (CC), non-small-lung cancer, cutaneous melanoma (CM) and glioblastoma were tested for TIL in hematoxylin eosin, and density of CD3+, CD4+, CD8+, CD20+, CD68+ and CD163+ cells by digital analysis. Results: TIL levels were higher in invasive margin compartments (IMC). TIL in IMC, intratumoral and stromal compartments predicted survival. CC and gastric cancer had higher TIL in intratumoral; CC and CM had higher TIL in stromal compartment and IMC. CM had the highest density of lymphocyte and macrophage populations. CD20 density was associated with survival in the whole series. Conclusion: Standardized evaluation of TIL levels may provide valuable prognostic information in a spectrum of different malignancies.

Tumor Protein p53 and K-ras Gene Mutations in Peruvian Patients with Gallbladder Cancer

Background: Recent studies have shown that genetic alterations are associated with the effect of patient geographic location on gallbladder cancer development. Peru has a high incidence of gallbladder cancer, but causative factors have not yet been identified. We examined the frequency of mutations in TP53 and K-ras genes in Peruvian patients with gallbladder cancer, and compared this with data from Bolivia, Hungary, Chile, and Japan, which have a high gallbladder cancer incidence. Methods: DNA was extracted from formalin-fixed paraffin-embedded gallbladder tissue sections of 30 gallbladder cancer patients (9 men and 21 women) obtained using microdissection. Mutations in exons 5 to 8 of TP53 and codons 12, 13, and 61 of K-ras were examined using direct sequencing. Results: TP53 mutations were observed in 10 (33.3%) of patients, but K-ras mutations were absent. Nine (90%) TP53 mutations were point mutations (7 missense and 2 silent mutations), and the most frequent substitution was a G:C to A:T transition. G:C to A:T transitions at the CpG site or G:C to T:A transversions were found in one patient each. No significant differences were found in the frequency of TP53 and K-ras mutations among patients in the 5 countries. Conclusions: Our findings suggest that endogenous mechanisms and exogenous carcinogens may affect the carcinogenic process in Peruvian gallbladder cancer patients, similar to that in Bolivian patients. Further studies with a larger sample size are needed to clarify these findings.

Breast cancer subtype and survival among Indigenous American women in Peru.

Latina women in the U.S. have relatively low breast cancer incidence compared to Non-Latina White (NLW) or African American women but are more likely to be diagnosed with the more aggressive "triple negative" breast cancer (TNBC). Latinos in the U.S. are a heterogeneous group originating from different countries with different cultural and ancestral backgrounds. Little is known about the distribution of tumor subtypes in Latin American regions. Clinical records of 303 female Peruvian patients, from the Peruvian National Cancer Institute, were analyzed. Participants were diagnosed with invasive breast cancer between 2010 and 2015 and were identified as residing in either the Selva or Sierra region. We used Fisher's exact test for proportions and multivariable Cox Proportional Hazards Models to compare overall survival between regions. Women from the Selva region were more likely to be diagnosed with TNBC than women from the Sierra region (31% vs. 14%, p = 0.01). In the unadjusted Cox model, the hazard of mortality was 1.7 times higher in women from the Selva than the Sierra (p = 0.025); this survival difference appeared to be largely explained by differences in the prevalence of TNBC. Our results suggest that the distribution of breast cancer subtypes differs between highly Indigenous American women from two regions of Peru. Disentangling the factors that contribute to this difference will add valuable information to better target prevention and treatment efforts in Peru and improve our understanding of TNBC among all women. This study demonstrates the need for larger datasets of Latin American patients to address differences between Latino subpopulations and optimize targeted prevention and treatment.