Population prevalence of hereditary breast cancer phenotypes and implementation of a genetic cancer risk assessment program in southern Brazil

Can paternal environmental experiences affect the breast cancer risk in offspring? A systematic review

INTRODUCTION

Studies in recent years have shown that parental environmental experiences can affect their offspring's risk of breast cancer (BC). We assessed the effect of different paternal factors on BC risk in offspring by reviewing the existing literature.

METHOD

This systematic review followed the Joanna Briggs Institute's (JBI) method for systematic reviews of qualitative evidence. The primary keywords were searched in reliable databases such as PubMed, Google Scholar, Elsevier, SID, and Wiley in English until 31 December 2021. Two authors independently examined the articles in terms of inclusion criteria and quality assessment of the articles.

RESULTS

Of the 438 studies, 19 met the inclusion criteria of this systematic review and were included in the study. Paternal factors investigated in these studies included age at delivery, diet, occupational exposures, occupation type and education. The reported relationships between these factors and breast cancer varied among different studies.

CONCLUSION

Studies considered in this article show that fathers' age at the time of delivery of the child, dietary habits, overweight and occupational factors can affect the incidence of BC risk in the next generation.

Germline molecular data in hereditary breast cancer in Brazil: Lessons from a large single-center analysis

Brazil is the largest country in South America and the most genetically heterogeneous. The aim of the present study was to determine the prevalence of germline pathogenic variants (PVs) in Brazilian patients with breast cancer (BC) who underwent genetic counseling and genetic testing at a tertiary Oncology Center. We performed a retrospective analysis of the medical records of Brazilian patients with BC referred to genetic counseling and genetic testing between August 2017 and August 2019. A total of 224 unrelated patients were included in this study. Premenopausal women represented 68.7% of the cohort. The median age at BC diagnosis was 45 years. Multigene panel testing was performed in 219 patients, five patients performed single gene analysis or family variant testing. Forty-eight germline PVs distributed among 13 genes were detected in 20.5% of the patients (46/224). Eighty-five percent of the patients (91/224) fulfilled NCCN hereditary BC testing criteria. Among these patients, 23.5% harbored PVs (45/191). In the group of patients that did not meet NCCN criteria, PV detection rate was 3% (1/33). A total of 61% of the patients (28/46) harbored a PV in a high-penetrance BC gene: 19 (8.5%) BRCA1/2, 8 (3.5%) TP53, 1 (0.5%) PALB2. Moderate penetrance genes (ATM, CHEK2) represented 15.2% (7/46) of the positive results. PVs detection was statistically associated (p<0.05) with BC diagnosis before age 45, high-grade tumors, bilateral BC, history of multiple primary cancers, and family history of pancreatic cancer. According to the current hereditary cancer guidelines, 17.4% (39/224) of the patients had actionable variants. Nine percent of the patients (20/224) had actionable variants in non-BRCA genes, it represented 43.5% of the positive results and 51.2% of the actionable variants. Considering the observed prevalence of PVs in actionable genes beyond BRCA1/2 (9%, 20/224), multigene panel testing may offer an effective first-tier diagnostic approach in this population.

Organophosphate Pesticide Exposure and Breast Cancer Risk: A Rapid Review of Human, Animal, and Cell-Based Studies

BACKGROUND

Organophosphate pesticides (OPs) are one of the most commonly used classes of insecticides in the U.S., and metabolites of OPs have been detected in the urine of >75% of the U.S.

POPULATION

While studies have shown that OP exposure is associated with risk of neurological diseases and some cancers, the relationship between OP exposure and breast cancer risk is not well understood.

METHODS

The aim of this rapid review was to systematically evaluate published literature on the relationship between OP exposure and breast cancer risk, including both epidemiologic and laboratory studies. Twenty-seven full-text articles were reviewed by searching on Pubmed, EMBASE, and Cochrane databases.

RESULTS

Some human studies showed that malathion, terbufos, and chlorpyrifos were positively associated with human breast cancer risk, and some laboratory studies demonstrated that malathion and chlorpyrifos have estrogenic potential and other cancer-promoting properties. However, the human studies were limited in number, mostly included agricultural settings in several geographical areas in the U.S., and did not address cumulative exposure.

CONCLUSIONS

Given the mixed results found in both human and laboratory studies, more research is needed to further examine the relationship between OP exposure and breast cancer risk, especially in humans in non-agricultural settings.

TP53 p.Arg337His germline mutation prevalence in Southern Brazil: Further evidence for mutation testing in young breast cancer patients

Premenopausal breast cancer (BC) is a core tumor of Li-Fraumeni (LFS) and Li-Fraumeni-like (LFL) Syndromes, predisposition disorders caused by germline mutations in TP53 gene. In the Southern and Southeastern regions of Brazil, a specific TP53 germline mutation, c.1010G>A (p.Arg337His), was identified at a population frequency of 0.3%, the highest value ever described for a TP53 germline variation. In Brazilian BC patients, carrier frequency can vary from 0.5% to 8.7%. The current study assessed carrier frequency by genotyping TP53 c.1010G>A in 2 BC groups: 1) 315 patients unselected for age of diagnosis and family history (FH) and 2) 239 patients diagnosed before 46 years and without Chompret criteria for LFS or LFL. One carrier was identified in group 1 (0.3%; CI 95% 0.1–1.76%) and six carriers in group 2 (2.5%; CI 95% 0.93–5.39%). The frequencies differed significantly between groups (p = 0.04). The mutation carrier frequency observed in group 2 could justify mutation testing in BC patients diagnosed before 46 years and without Chompret criteria for LFS or LFL. Further studies in larger samples of BC patients of different ages and regions of the country are necessary to provide more definitive TP53 p.Arg337His carrier frequencies in different scenarios.

Identification of hereditary cancer in the general population: development and validation of a screening questionnaire for obtaining the family history of cancer

One of the challenges for Latin American countries is to include in their healthcare systems technologies that can be applied to hereditary cancer detection and management. The aim of the study is to create and validate a questionnaire to identify individuals with possible risk for hereditary cancer predisposition syndromes (HCPS), using different strategies in a Cancer Prevention Service in Brazil. The primary screening questionnaire (PSQ) was developed to identify families at‐risk for HCPS. The PSQ was validated using discrimination measures, and the reproducibility was estimated through kappa coefficient. Patients with at least one affirmative answer had the pedigree drawn using three alternative interview approaches: in‐person, by telephone, or letter. Validation of these approaches was done. Kappa and intraclass correlation coefficients were used to analyze data's reproducibility considering the presence of clinical criteria for HCPS. The PSQ was applied to a convenience sample of 20,000 women of which 3121 (15.6%) answered at least one affirmative question and 1938 had their pedigrees drawn. The PSQ showed sensitivity and specificity scores of 94.4% and 75%, respectively, and a kappa of 0.64. The strategies for pedigree drawing had reproducibility coefficients of 0.976 and 0.850 for the telephone and letter approaches, respectively. Pedigree analysis allowed us to identify 465 individuals (24.0%) fulfilling at least one clinical criterion for HCPS. The PSQ fulfills its function, allowing the identification of HCPS at‐risk families. The use of alternative screening methods may reduce the number of excluded at‐risk individuals/families who live in locations where oncogenetic services are not established.

Contribution of the TP53 R337H mutation to the cancer burden in southern Brazil: Insights from the study of 55 families of children with adrenocortical tumors

BACKGROUND

The tumor protein p53 (TP53) arginine-to-histidine mutation at codon 337 (R337H) predisposes children to adrenocortical tumors (ACTs) and, rarely, to other childhood tumors, but its impact on adult cancer remains undetermined. The objective of this study was to investigate the frequency and types of cancer in relatives of children with ACT who carry the TP53 R337H mutation.

METHODS

TP53 R337H testing was offered to relatives of probands with ACT. The parental lineage segregating the R337H mutation was identified in all families. The frequency and distribution of cancer types were compared according to R337H status. The authors' data also were compared with those publicly available for children with TP53 mutations other than R337H.

RESULTS

The mean and median follow-up times for the probands with ACT were 11.2 years and 9.7 years (range, 3-32 years), respectively. During this time, cancer was diagnosed in 12 of 81 first-degree relatives (14.8%) carrying the R337H mutation but in only 1 of 94 noncarriers (1.1%; P = .0022). At age 45 years, the cumulative risk of cancer was 21% (95% confidence interval, 5%-33%) in carriers and 2% (95% confidence interval, 0%-4%) in noncarriers (P = .008). The frequency of cancer was higher in the R337H segregating lineages than in the nonsegregating lineages (249 of 1410 vs 66 of 984 individuals; P < .001). Breast and gastric cancer were the most common types.

CONCLUSIONS

TP53 R337H carriers have a lifelong predisposition to cancer with a bimodal age distribution: 1 peak, represented by ACT, occurs in the first decade of life, and another peak of diverse cancer types occurs in the fifth decade. The current findings have implications for genetic counseling and surveillance of R337H carriers. Cancer 2017;123:3150-58. © 2017 American Cancer Society.

Self-reported cancer family history is a useful tool for identification of individuals at risk of hereditary cancer predisposition syndrome at primary care centers in middle-income settings: a longitudinal study

Analysis of cancer family history (CFH) offers a low-cost genetic tool to identify familial cancer predisposition. In middle-income settings, the scarcity of individual records and database-linked records hinders the assessment of self-reported CFH consistency as an indicator of familial cancer predisposition. We used self-reported CFH to identify those families at risk for hereditary cancer syndromes in community-based primary care centers of a low-income Brazilian area. We also evaluated the consistency of the information collected by reassessing CFH five years later. We interviewed 390 families and constructed their pedigrees for genetic cancer risk assessment. We found 125 families affected by cancer, 35.2% with moderate to high risk of familial susceptibility to cancer, a number that represents a relatively high prevalence of potential hereditary cancer syndromes in the overall study sample. Upon reassessment of CFH in 14/20 families that were previously identified as having at least one first-degree and one second-degree relative affected by cancer, and presented moderate to high risk for developing cancer, 90% of initial pedigrees were confirmed. These results demonstrate the reliability of self-reports as a means of early identification of healthy individuals at risk, encouraging the wider use of this method in low- and middle-income primary care settings.

Screening for germline BRCA1, BRCA2, TP53 and CHEK2 mutations in families at-risk for hereditary breast cancer identified in a population-based study from Southern Brazil

In Brazil, breast cancer is a public health care problem due to its high incidence and mortality rates. In this study, we investigated the prevalence of hereditary breast cancer syndromes (HBCS) in a population-based cohort in Brazils southernmost capital, Porto Alegre. All participants answered a questionnaire about family history (FH) of breast, ovarian and colorectal cancer and those with a positive FH were invited for genetic cancer risk assessment (GCRA). If pedigree analysis was suggestive of HBCS, genetic testing of the BRCA1, BRCA2, TP53, and CHEK2 genes was offered. Of 902 women submitted to GCRA, 214 had pedigrees suggestive of HBCS. Fifty of them underwent genetic testing: 18 and 40 for BRCA1/BRCA2 and TP53 mutation screening, respectively, and 7 for CHEK2 1100delC testing. A deleterious BRCA2 mutation was identified in one of the HBOC probands and the CHEK2 1100delC mutation occurred in one of the HBCC families. No deleterious germline alterations were identified in BRCA1 or TP53. Although strict inclusion criteria and a comprehensive testing approach were used, the suspected genetic risk in these families remains unexplained. Further studies in a larger cohort are necessary to better understand the genetic component of hereditary breast cancer in Southern Brazil.

Translating Population Difference: The Use and Re-Use of Genetic Ancestry in Brazilian Cancer Genetics

In the past ten years, there has been an expansion of scientific interest in population genetics linked to both understanding histories of human migration and the way that population difference and diversity may account for and/or be implicated in health and disease. In this article, I examine how particular aspects of a globalizing research agenda related to population differences and genetic ancestry are taken up in locally variant ways in the nascent field of Brazilian cancer genetics. Drawing on a broad range of ethnographic data from clinical and nonclinical contexts in the south of Brazil, I examine the ambiguities that attention to genetic ancestry generates, so revealing the disjunctured and diverse ways a global research agenda increasingly orientated to questions of population difference and genetic ancestry is being used and reused.

Knowledge about breast cancer and hereditary breast cancer among nurses in a public hospital

OBJECTIVE:

To assess the knowledge of nurses involved in the care of oncology patients in a public university hospital, regarding breast cancer and hereditary breast cancer, and to verify the use of such knowledge in their daily practice.

METHODS:

This is a descriptive cross-sectional study. Data were obtained through a structured, self-administered questionnaire. Out of 154 nurses, 137 (88.9%) agreed to participate in the study. Two questionnaires were excluded such that 135 questionnaires were analyzed.

RESULTS:

The global percentage of correct answers was not associated with age (p=0.173) or degree/specialization (p=0.815). Questions were classified into categories. In categories involving knowledge of established breast cancer risk factors and indicators of hereditary breast cancer, the rate of correct answers was 65.8% and 66.4%, respectively. On the practice of genetic counseling, 40.7% of those interviewed were not sure about the definition of genetic counseling and 78.5% reported never having identified or referred a patient at genetic risk for specialized risk assessment. Practice of educational actions regarding this subject was reported by 48.5% of those interviewed.

CONCLUSION:

This study reinforces the need to develop qualifying actions for nurses, so that strategies to control breast cancer become effective in their health care practice.

Knowledge about hereditary cancer of women with family histories of breast, colorectal, or both types of cancer

Usually, the mass media do not address hereditary cancer and their risk factors, nor are these topics discussed at the community level. We used an informative guide on cancer and hereditary cancer, followed by a questionnaire on these topics to investigate the relevant knowledge among women at high risk for hereditary breast and/or colorectal cancer from a population-based cohort. The cohort was composed of 81 Brazilian women with positive family histories of breast and/or colorectal cancer. Strauss and Corbin's Grounded Theory was used for qualitative analysis. The average age of the cohort was 49.9 years old. Three participants (3.9%) were illiterate, 45 (59.2%) had attended elementary school, 14 (18.4%) had secondary school, and 14 (18.4%) held higher education degrees. A total of 47 (54.3%) volunteers were unable to fully understand the information provided in the guide because they did not know the meaning of words such as metastasis, malignant, hereditary, sporadic, or oncogenetics. Notwithstanding, the acceptance of the educational tool utilized was satisfactory, and it enhanced the volunteers' interest in a better understanding of cancer and heredity. Thereby, we concluded that the low knowledge of this important subject and the unawareness about fundamental terms required for the comprehension of this specific type of neoplasm made us believe that the use of the informative guide can provide a great value when used previously to the genetic counseling consultations. Besides, educational tools of easy understanding should be part of everyday clinical practice, from primary to specialized patient care.

Establishing a program for individuals at high risk for breast cancer

Our need to create a program for individuals at high risk for breast cancer development led us to research the available data on such programs. In this paper, we summarize our findings and our thinking process as we developed our own program. Breast cancer incidence is increasing worldwide. Even though there are known risk factors for breast cancer development, approximately 60% of patients with breast cancer have no known risk factor, although this situation will probably change with further research, especially in genetics. For patients with risk factors based on personal or family history, different models are available for assessing and quantifying risk. Assignment of risk levels permits tailored screening and risk reduction strategies. Potential benefits of specialized programs for women with high breast cancer risk include more cost -effective interventions as a result of patient stratification on the basis of risk; generation of valuable data to advance science; and differentiation of breast programs from other breast cancer units, which can result in increased revenue that can be directed to further improvements in patient care. Guidelines for care of patients at high risk for breast cancer are available from various groups. However, running a high-risk breast program involves much more than applying a guideline. Each high-risk program needs to be designed by its institution with consideration of local resources and country legislation, especially related to genetic issues. Development of a successful high-risk program includes identifying strengths, weaknesses, opportunities, and threats; developing a promotion plan; choosing a risk assessment tool; defining "high risk"; and planning screening and risk reduction strategies for the specific population served by the program. The information in this article may be useful for other institutions considering creation of programs for patients with high breast cancer risk.

Adherence to a breast cancer screening program and its predictors in underserved women in southern Brazil

BACKGROUND

Adherence to breast cancer screening is a key element to ensure effectiveness of programs aiming at downstaging of breast cancer. In this study, we evaluated adherence to a screening program and its predictors in underserved women in southern Brazil.

METHODS

Attendance to the program, which is based on yearly mammogram and clinical examination, was evaluated prospectively. Mean time frames between visits were calculated. Possible predictors of adherence (defined as mean intervals ≤18 mo), such as socioeconomic indicators and health/lifestyle behaviors, were investigated.

RESULTS

A total of 3,749 women (age 51 ± 8 y, illiteracy rate of 6.8%, 57.4% with parity ≥3) were analyzed. Median time between screening rounds was 16.5 months (interquartile range, 13.1-25.7), and median number of rounds attended was 3 (interquartile range, 2-4); 57.6% had mean intervals ≤18, and 71% ≤24 months. The most important independent predictors of adherence were high genetic risk [relative risk (RR), 1.25; 95% confidence interval (95% CI), 1.11-1.40], illiteracy (RR, 0.77; 95% CI, 0.67-0.90), parity ≥5 (RR, 0.89; 95% CI, 0.83-0.96), and smoking (RR, 0.82; 95% CI, 0.77-0.88).

CONCLUSIONS

Although the proposed screening interval was 1 year, compliance to biannual screening (accepted in several international programs) was high, especially when considering the low socioeconomic level of the sample.

IMPACT

This project aims to test a breast cancer screening model for underserved populations in limited-resource countries where adherence is an issue. The identification of worst adherence predictors can point to interventions to improve outcomes of similar public health screening strategies.

Development and validation of a simple questionnaire for the identification of hereditary breast cancer in primary care

Background

Breast cancer is a significant public health problem worldwide and the development of tools to identify individuals at-risk for hereditary breast cancer syndromes, where specific interventions can be proposed to reduce risk, has become increasingly relevant. A previous study in Southern Brazil has shown that a family history suggestive of these syndromes may be prevalent at the primary care level. Development of a simple and sensitive instrument, easily applicable in primary care units, would be particularly helpful in underserved communities in which identification and referral of high-risk individuals is difficult.

Methods

A simple 7-question instrument about family history of breast, ovarian and colorectal cancer, FHS-7, was developed to screen for individuals with an increased risk for hereditary breast cancer syndromes. FHS-7 was applied to 9218 women during routine visits to primary care units in Southern Brazil. Two consecutive samples of 885 women and 910 women who answered positively to at least one question and negatively to all questions were included, respectively. The sensitivity, specificity and positive and negative predictive values were determined.

Results

Of the 885 women reporting a positive family history, 211 (23.8%; CI95%: 21.5–26.2) had a pedigree suggestive of a hereditary breast and/or breast and colorectal cancer syndrome. Using as cut point one positive answer, the sensitivity and specificity of the instrument were 87.6% and 56.4%, respectively. Concordance between answers in two different applications was given by a intra-class correlation (ICC) of 0.84 for at least one positive answer. Temporal stability of the instrument was adequate (ICC = 0.65).

Conclusion

A simple instrument for the identification of the most common hereditary breast cancer syndrome phenotypes, showing good specificity and temporal stability was developed and could be used as a screening tool in primary care to refer at-risk individuals for genetic evaluations.

A model to optimize public health care and downstage breast cancer in limited-resource populations in southern Brazil. (Porto Alegre Breast Health Intervention Cohort)

Background

Breast cancer (BC) is a major public health problem, with rising incidence in many regions of the globe. Although mortality has recently dropped in developed countries, death rates are still increasing in some developing countries, as seen in Brazil. Among the reasons for this phenomenon are the lack of structured screening programs, a long waiting period between diagnosis and treatment, and lack of access to health services for a large proportion of the Brazilian population.

Methods and design

Since 2004, an intervention study in a cohort of women in Southern Brazil, denominated Porto Alegre Breast Health Intervention Cohort, is being conducted in order to test the effectiveness and cost-effectiveness of a model for BC early detection and treatment. In this study, over 4,000 women from underserved communities aged 40 to 69 years are being screened annually with mammography and clinical breast examination performed by a multidisciplinary team, which also involves nutritional counseling and genetic cancer risk assessment. Risk factors for BC development are also being evaluated. Active search of participants by lay community health workers is one of the major features of our program. The accrual of new participants was concluded in 2006 and the study will last for 10 years. The main goal of the study is to demonstrate significant downstaging of BC in an underserved population through proper screening, attaining a higher rate of early-stage BC diagnoses than usually seen in women diagnosed in the Brazilian Public Health System. Preliminary results show a very high BC incidence in this population (117 cases per 100,000 women per year), despite a low prevalence of classical risk factors.

Discussion

This study will allow us to test a model of BC early diagnosis and treatment and evaluate its cost-effectiveness in a developing country where the mortality associated with this disease is very high. Also, it might contribute to the evaluation of risk factors in a population with a different ethnic background from that studied in developed countries. If our model is proven effective, it may be replicated in other parts of the globe where BC is also a major public health problem.