ORIGINAL ARTICLE
Characterization of Patients with Breast Cancer and National Comprehensive Cancer Network Criteria for Performing BRCA1 and BRCA2 Genetic Test
Caracterização de Pacientes com Câncer de Mama e Critérios da National Comprehensive Cancer Network para Realização do Teste Genético BRCA1 e BRCA2
Caracterización de Pacientes con Cáncer de Mama y Criterios de la National Comprehensive Cancer Network para Realizar Prueba Genética de BRCA1 y BRCA2
https://doi.org/10.32635/2176-9745.RBC.2023v69n4.4214
Rafael Armando Seewald1; André Anjos da Silva2; Guilherme Liberato da Silva3; Álvaro Ortigara Maciel4; Fernando Mateus Mascarello5; Natália Lenz Follmann6; Gabriela Laste7
1-7Universidade do Vale do Taquari (Univates). Lajeado (RS), Brazil.
1E-mail: rafael.seewald@univates.br. Orcid iD: https://orcid.org/0009-0005-9321-2348
2E-mail: andre.silva3@univates.br. Orcid iD: https://orcid.org/0000-0003-3714-3171
3E-mail: gibaliberato@univates.br. Orcid iD: https://orcid.org/0000-0001-6619-6622
4E-mail: alvaro.maciel@universo.univates.br. Orcid iD: https://orcid.org/0000-0003-1167-4433
5E-mail: fernando.mascarello@universo.univates.br. Orcid iD: https://orcid.org/0009-0008-0292-2347
6E-mail: natalia.follmann@universo.univates.br. Orcid iD: https://orcid.org/0009-0001-1598-9005
7E-mail: gabrielalaste@univates.br. Orcid iD: https://orcid.org/0000-0003-1554-6658
Corresponding author: Gabriela Laste. Programa de Pós-Graduação em Ciências Médicas da Univates. Rua Avelino Talini, 171 – Bairro Universitário. Lajeado (RS), Brazil. CEP 95914-014. E-mail gabrielalaste@univates.br
ABSTRACT
Introduction: Approximately 10% of breast cancer cases are attibutable to germinative mutations in susceptibility genes, including BRCA1, BRCA2 and others. The National Comprehensive Cancer Network (NCCN) recommends screening women with breast cancer for mutations in BRCA1/2 in defined scenarios. However, these genetic tests are unavailable at the Brazilian Public Health System (SUS). Objective: This study aimed to characterize women with breast cancer and define the criteria for performing BRCA1/2 test. Method: Quantitative, descriptive, analytic, and retrospective study. Medical records of women diagnosed by SUS with breast cancer between January 2016 and December 2018 were analyzed through the software JAMOVI (version 2.3 - 2022). Results: A total of 245 women were diagnosed. According to NCCN guidelines, 97 women met the criteria for performing BRCA1/2 test, with mean age of 47 years old, predominantly white (90,7%), with comorbidities (55.6%), premenopausal (59.8%), diagnosed in early stages 0 - IIb (68.2%) and 48.4% had familial history of breast cancer. Most frequent histology and molecular subtype was invasive ductal carcinoma (87.2%) and luminal type (59.8%). Conclusion: A significant number of women diagnosed by SUS had indication for BRCA1/2 test. These women are younger, had fewer comorbidities, not menopausal, and differ in terms of the molecular subtype when compared with those without indication for performing the test.
Key words: breast neoplasms; ovarian neoplasms; hereditary breast and ovarian cancer syndrome; genes BRCA1.
RESUMO
Introdução: Aproximadamente 10% dos casos de câncer de mama são atribuíveis a mutações germinativas em genes de suscetibilidade, incluindo BRCA1 e BRCA2. A National Comprehensive Cancer Network (NCCN) recomenda a triagem de mulheres com câncer de mama para mutações em BRCA1/2 em cenários definidos. No entanto, esses testes genéticos não estão disponíveis no Sistema Único de Saúde (SUS). Objetivo: Caracterizar as mulheres com câncer de mama e definir os critérios para realização do teste BRCA1/2. Método: Estudo quantitativo, descritivo, analítico e retrospectivo. Foram analisados prontuários de mulheres com diagnóstico de câncer de mama pelo SUS entre janeiro de 2016 e dezembro de 2018, por meio do software JAMOVI (versão 2.3 - 2022). Resultados: Foram diagnosticadas 245 mulheres. De acordo com as diretrizes da NCCN, 97 mulheres atenderam aos critérios para realizar o teste BRCA1/2, com idade média de 47 anos, predominantemente brancas (90,7%), com comorbidades (55,6%), na pré-menopausa (59,8%), diagnosticadas nos estágios iniciais 0 - IIb (68, 2%), e 48,4% tinham histórico familiar de câncer de mama. A histologia e o subtipo molecular mais frequentes foram carcinoma ductal invasivo (87,2%) e tipo luminal (59,8%). Conclusão: Considerando os critérios da NCCN, um número significativo de mulheres diagnosticadas pelo SUS teve indicação para realização do teste BRCA1/2. Essas mulheres são mais jovens, têm menos comorbidades, estão em período pré-menopausa mais frequentemente e diferem quanto ao subtipo molecular quando comparadas àquelas sem indicação de realização do exame.
Palavras-chave: neoplasias da mama; neoplasias ovarianas; síndrome hereditária de câncer de mama e ovário; genes, BRCA1.
RESUMEN
Introducción: Aproximadamente el 10% de los casos de cáncer de mama son atribuibles a mutaciones germinales en genes de susceptibilidad, incluidos BRCA1 y BRCA2. La National Comprehensive Cancer Network (NCCN) recomienda la detección de mutaciones BRCA1/2 en mujeres con cáncer de mama en entornos definidos. Sin embargo, estas pruebas genéticas no están disponibles en el Sistema Único de Salud (SUS). Objetivo: Caracterizar mujeres con cáncer de mama y definir los criterios para la realización de la prueba BRCA1/2. Método: Estudio cuantitativo, descriptivo, analítico y retrospectivo. Las historias clínicas de las mujeres diagnosticadas con cáncer de mama entre enero de 2016 y diciembre de 2018, usuarias del SUS, fueron analizadas mediante el software JAMOVI (versión 2.3 - 2022). Resultados: 245 mujeres fueron diagnosticadas. Según las pautas de NCCN, 97 mujeres cumplieron con los criterios para someterse a la prueba BRCA1/2. Las mujeres con indicación para la prueba tenían un promedio de edad de 47 años, eran predominantemente blancas (90,7%), con comorbilidades (55,6%), premenopáusicas (59,8%), diagnosticadas en estadios tempranos 0 - IIb (68,2%) y 48,4% tenía antecedentes familiares de cáncer de mama. Los subtipos histológicos y moleculares más frecuentes fueron el carcinoma ductal invasivo (87,2%) y el tipo luminal (59,8%). Conclusión: Considerando los criterios de la NCCN, un número significativo de mujeres, usuarias del SUS, fueron designadas para hacer la prueba BRCA1/2. Estas mujeres son más jóvenes, tienen menos comorbilidades, están en el periodo de la premenopausia con mayor frecuencia y difieren en el subtipo molecular en comparación con aquellas sin orden de realizarse la prueba.
Palabras clave: neoplasias de la mama; neoplasias ováricas; síndrome de cáncer de mama y ovario hereditario; genes BRCA1.
INTRODUCTION
Breast cancer is the second most prevalent neoplasm globally, with approximately 2 million cases annually, and is the leading cause of cancer-related deaths among women1. In Brazil, 704,000 new cases of cancer are estimated for each year of the triennium 2023-20252. The majority of breast cancer cases occur sporadically associated with somatic genetic alterations. However, approximately 10% of the cases result from germline mutations, primarily caused by inherited mutations in the BRCA1 and BRCA2 genes; less frequently, they may also be associated with other inherited syndromes3,4.
The BRCA1 and BRCA2 genes encode homologous proteins responsible for repairing DNA damage, particularly double-strand breaks. If not repaired properly, these breaks can lead to an accumulation of mutations in the DNA5 and ultimately contribute to carcinogenesis. Individuals who carry pathogenic variants in the BRCA1 and BRCA2 genes have a significantly higher risk of developing new primary tumors compared to those without the variants6,7. Additionally, the risk of ovarian cancer is 44% for those with pathogenic variants in BRCA1 and 17% in BRCA28.
Prophylactic contralateral mastectomy in patients with pathogenic variants in BRCA1 and BRCA2 genes is associated with a reduction of 95% in the incidence of breast cancer9. Similarly, prophylactic bilateral salpingoophorectomy in these patients can significantly reduce the risk of developing ovarian cancer10,11. Therefore, it is currently recommended that these patients undergo prophylactic contralateral mastectomy and bilateral salpingoophorectomy12.
Additionally, identifying a carrier of a pathogenic variant in BRCA1 and BRCA2 enables the identification of other family members who may also carry the variant, allowing them to be offered appropriate therapies to reduce their risk of developing cancer13. The National Comprehensive Cancer Network (NCCN) guidelines recommend screening for BRCA1 and BRCA2 genes in specific scenarios for patients diagnosed with breast cancer12. According to NCCN criteria, patients from a similar geographic population with indications for BRCA1 and BRCA2 gene testing have a 13.5% and 9.3% chance, respectively, of having a mutation in these genes14. In a large patient database from the “Hospital do Câncer de Barretos” in Brazil, the probability is 18%15 .
A recent study has shown that the strategy of testing pathogenic variants in BRCA1 and BRCA2 genes and implementing preventive measures, such as prophylactic bilateral mastectomy and salpingoophorectomy, is cost-effective in the context of the Brazilian Public Health System (SUS)15. This finding provides strong support for implementing testing strategies for high risk patients, as it not only prevents new cases of cancer but also reduces costs to the healthcare system.
Despite extensive knowledge of the risks of developing cancer in individuals with pathogenic variants in BRCA1 and BRCA2 and the benefits of performing prophylactic surgical procedures and the existence of a formal recommendation for testing in well-defined scenarios, the access to testing BRCA1 and BRCA2 is non-existent in SUS16. To achieve this, it is crucial to understand the epidemiological, clinical, and pathological profile of women diagnosed with breast cancer, as well as the number and characteristics of women who, upon diagnosis, would be eligible for testing for pathogenic variants in the BRCA1 and BRCA2 genes.
It is believed that a significant number of women diagnosed with breast cancer meet the criteria for genetic testing for BRCA1 and BRCA2. Therefore, the purpose of this study is to identify and describe the characteristics of women diagnosed with breast cancer who meet the criteria for testing for pathogenic variants in BRCA1 and BRCA2 according to NCCN guidelines.
METHOD
Retrospective, quantitative and descriptive analysis of medical records of women diagnosed with histologically confirmed breast cancer (International Classification of Diseases, 10th Revision – ICD1017 C50) between January 2016 and December 2018, consulted at SUS and at a High Complexity Oncology Unit (UNACON) in a reference hospital located in Vale do Taquari, Rio Grande do Sul, Brazil.
Data on the epidemiological profile (age, place of residence, skin color), clinical characteristics (risk factors, family history of breast cancer and other cancers, presence of comorbidities, menopausal status), and pathological features (histological type, molecular profile, clinical stage at diagnosis) were collected from the electronic medical records of the patients and organized in Excel spreadsheets. Patients who met the criteria for testing pathogenic variants in BRCA1 and BRCA2 at the time of diagnosis according to the NCCN - 2020 guidelines were identified.
The data were analyzed using the statistical program JAMOVI (version 2.3)18 [Computer Software] (2022). The Kolmogorov-Smirnov test was used to assess the normality of the data. Non-parametric continuous data were analyzed using the Mann-Whitney U-test and presented as mean + standard deviation (SD). The number and percentage were presented as n (%) and nominal and ordinal categorical variables were analyzed using the chi-square test (x2) and Fisher's exact test. A p value of < 0.05 was considered statistically significant for the analyses.
The Institutional Review Board of Univates (COEP) approved the study, report number 4,607,477, CAAE (submission for ethical review): 44455721.9.0000.5310, in compliance with Resolution 466/201219 of the National Health Council, which waives the informed consent form for retrospective and secondary data based studies.
RESULTS
The medical records of 245 women diagnosed with breast cancer between the years 2016 and 2018 were analyzed. Of these 245 medical records analyzed, 230 women (93.9%) were white and 176 (71.8%) lived in urban areas; at diagnosis, the mean age was 56+12.8 years, mostly menopausal (59.6%), with breast cancer related comorbidities (73.8%), and systemic arterial hypertension (SAH) was the most prevalent comorbidity (46.9%). In addition, 59.6% were postmenopausal at diagnosis, 26.5% were previously screened for breast cancer, and the objective of the diagnosis of breast cancer was to detect symptoms (51.4%). Most women had no personal history of breast cancer (87.3%); 75 (30.6%) women had family history of breast cancer, 48% had first degree family member affected by breast cancer , and 110 (44.9%) had family history of other types of cancer (Table 1).
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Table 1. Sociodemographic and clinical characteristics of patients diagnosed with breast cancer between 2016 and 2018 (n=245) |
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The most common histological type was invasive ductal carcinoma, present in 215 women (87.7%), followed by lobular carcinoma in 12 (4.9%) women. The most common molecular subtype was luminal tumors, followed by HER2 positive and triple-negative tumors, present in 169 (69%), 45 (18.4%), and 28 (11.4%) patients, respectively (Table 2).
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Table 2. Pathological characteristics of women diagnosed with breast cancer between 2016 and 2018 (n=245) |
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Source: Brierley JD, Gospodarowicz MK, Wittekind C20. |
Most women were diagnosed at early stages of the disease according to the 8th edition of the TNM20 – Classification of Malignant Tumors of the American Joint Committee on Cancer (AJCC) and The Union for International Cancer Control (UICC), with 66 (26.9%) at stage IA, 3 (1.2%) at stage IB, 71 (29%) at stage IIA, and 27 (11%) at stage IIB. Advanced stages were less common, with 19 (7.8%), 21 (8.6%), and 12 (4.9%) patients diagnosed with stage IIIA, IIIB, and IIIC, respectively. Only 10 (4.1%) women were diagnosed with stage IV, and bones were the most common site of metastasis. Additionally, 16 patients (6.5%) were diagnosed with tumors in situ (clinical stage 0) (Table 2).
Regarding the pathogenic variants in BRCA1 and BRCA2 genes at diagnosis, 97 (39.6%) patients met the criteria according to the NCCN guidelines and 148 (60.4%) did not. The most frequent criteria that would indicate the necessity for further investigation were: diagnosis of breast cancer before 45 years (20%) and diagnosis of breast cancer at any age with 1st, 2nd, or 3rd degree relatives diagnosed with breast cancer before 50 years, or metastatic ovarian, pancreatic, or prostate cancer at any age (8.6%) (Table 3).
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Table 3. Eligibility Criteria for BRCA1 and BRCA2 genetic testing among women diagnosed with breast cancer between 2016 and 2018 (n=245) |
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(*) 1 – Breast cancer diagnosed before age 45; 2 – Breast cancer diagnosed between ages 46 and 50 with: unknown or limited family history; new primary breast cancer diagnosis at any age; >1 case of breast, ovarian, pancreatic, or prostate cancer in a 1st, 2nd, or 3rd degree relative diagnosed at any age; 3 – Breast cancer diagnosed at any age in Ashkenasi Jews; 4 – Breast cancer diagnosed at any age in Ashkenasi Jews. Triple-negative breast cancer diagnosed before age 60; 5 – Breast cancer diagnosed at any age with a 1st, 2nd, or 3rd degree relative diagnosed with breast cancer before 50 years, or metastatic ovarian, pancreatic, or prostate cancer at any age12. |
Among women with indication for pathogenic variants tests in BRCA1 and BRCA2, 54 (55.6%) had comorbidities at diagnosis, versus 127 (85.8%) without any indications (p < 0.001). The mean age at diagnosis for women with indication was 47.7+11.6 years, while those without indication, it was 62+11.6 years (p < 0.001). In terms of menopausal status, 33 (34%) women with indication were menopausal and 58 (59.8%) were premenopausal, while those without indication, 113 (76.3%) and 21 (14.2%) were menopausal and premenopausal, respectively (p < 0.001). There was no statistically significant difference in the skin color of women with and without indication for genetic testing. Previous breast cancer screening was more frequent in women who did not meet the criteria 42 (28.4%) (p < 0.05). However, there was no difference in the method of breast cancer diagnosis (p > 0.05) (Table 4).
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Table 4. Sociodemographic and clinical characteristics of patients diagnosed with breast cancer between 2016 and 2018 that met and did not meet the criteria for BRCA1 and BRCA2 genetic testing (n=245) |
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(*) Analyzed using the chi-square test (x2) and Fisher's exact test; p < 0.05 was considered statistically significant for all analyses. (**) Analyzed using the Mann-Whitney U-test. |
Among women with indication for testing, 47 (48.4%) had family history of breast cancer, while those without indication, only 29 (19.6%) had family history of breast cancer (p < 0.001). There was no difference between groups of family members affected by breast cancer (p > 0.05). Family history of other types of cancer was present in 44 patients (45.4%) with indication and 66 (44.6%) without indication. There was no difference between women with indication and without indication regarding residential area, comorbidities, and personal history of breast cancer (p > 0.05 for all) (Table 4).
Ductal carcinoma and histological grade 2 was the most prevalent histological type among patients with and without indication for BRCA1 and BRCA2 genetic testing, however there was no difference between groups (p > 0.05). Women with indication for genetic testing were more likely to have luminal tumors, followed by triple-negative and HER2-positive tumors, present in 59.8%, 22.7%, and 16.5% respectively. In contrast, among those without indication, the most common molecular subtype was also luminal tumors, present in 75% of the cases, followed by HER2-positive tumors (19.6%), and less frequently, triple-negative tumors (4.1%) (p < 0.001). The clinical stages IIA and IA were the most frequent, however there was no significant difference between groups with and without indication (p > 0.05) (Table 5).
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Table 5. Pathological characteristics of patients diagnosed with breast cancer between 2016 and 2018 that met and did not meet the criteria for BRCA1 and BRCA2 genetic testing (n=245) |
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Source: Brierley JD, Gospodarowicz MK, Wittekind C20. (*) Analyzed using the chi-square test (x2) and Fisher's exact test; p value of < 0.05 was considered statistically significant for all analyses. |
DISCUSSION
This study enabled to determine the number of women diagnosed with breast cancer who met the criteria of the NCCN guidelines for genetic testing of pathogenic variants in BRCA1 and BRCA2 in Brazil’s southern region; the epidemiological, clinical, and pathological characteristics of these women were analyzed. As expected, a considerable number of women diagnosed with breast cancer in the Vale do Taquari region, located in the state of Rio Grande do Sul met the criteria for genetic testing.
During the years 2016-2018, a total of 245 women were diagnosed with breast cancer and received treatment at the UNACON, with an average age of 56 years at diagnosis and the majority were white (93.9%). This finding aligns with the population demographics of the Vale do Taquari region, where UNACON is located, which has a significant population of German and Italian descent. Furthermore, this result is consistent with data from Population-Based Cancer Registries (RCBP), where the median age at breast cancer diagnosis was 56 years in Brazil between 2000 and 201021.
The majority of the women (51%) had suspected breast cancer diagnosis due to symptoms or changes found during physical examination, and only 31% were diagnosed as a result of an abnormal screening test. Additionally, only 28.2% of the women were submitted to prior screening before their diagnosis. These findings highlight the necessity to increase adherence to breast cancer screening programs among women in this region through ongoing awareness efforts which are not limited to international awareness campaigns such as "Outubro Rosa".
Nevertheless, most women (74.6%) were diagnosed at early stages of breast cancer (stages 0-IIb), the majority (29%) at stage IIa. National data from the Hospital Cancer Registry (RHC) indicate that 65% of the women are diagnosed at early stages21, which is lower than the findings of this study. The high proportion of white women may have contributed to this difference, as studies have shown that this ethnicity is more likely to be diagnosed with breast cancer at early stages than black women22,23. It is noteworthy that, as stated by Amin MB24, the prognosis for early stages of the disease is favorable, with a 5-year disease-free survival rate of 98-100% for stage I and 85-98% for stage II24.
Similar to previous studies, the most frequently observed histological subtype was invasive ductal carcinoma (IDC) and the most common molecular subtype was luminal tumors, with IDC representing 87.2% of cases, which is higher than the commonly reported range of 70-80% in the literature25. Additionally, the prevalence of other molecular subtypes, such as HER2-positive tumors (23%) and triple-negative subtypes (13%), was consistent with findings reported by Parise et al.26.
According to UNACON-SUS, 39.7% of the women diagnosed with breast cancer between 2016 and 2018 met the criteria for genetic testing for pathogenic variants in the BRCA1 and BRCA2 genes according to the NCCN guidelines from 2020, consistent with previous studies, where approximately 40% of breast cancer patients met these criteria, with range of 35-47.9% reported in the literature27,28. The current findings concur with the study by Borges et al28 which found that the most common criterion for genetic testing was a diagnosis of breast cancer before the age of 45, present in 21% of their sample and 20% of the sample investigated. However, the criterion of a triple-negative tumor subtype diagnosis before the age of 60 was the second most prevalent in their study, present in 12% of patients, while it was the least frequent in only 6% of the patients investigated.
The analysis revealed that women who met the criteria for genetic testing for pathogenic variants in the BRCA1 and BRCA2 genes (with a mean age of 47.7 years) were significantly younger than those without indication for testing (with a mean age of 62 years). Additionally, the majority of these women were premenopausal at diagnosis, with a mean age of menopause of 49 years. This age difference meets the NCCN guidelines of early age at the diagnosis as criterion for genetic testing.
Women who met the criteria for genetic testing for pathogenic variants in the BRCA1 and BRCA2 genes were more likely to have a family history of cancer than those who did not meet the criteria; this supports the use of family history as a criterion for genetic testing according to the NCCN guidelines. Specifically, 15.5% of women had an indication for genetic testing based on a family history of cancer. Additionally, a personal history of prior breast cancer was more common among women who met the criteria for genetic testing.
A significant number of women had no documentation of family history of breast cancer in their medical records. This information is crucial not only to determine the indication for genetic testing for pathogenic variants in the BRCA1 and BRCA2 genes, but also for recommending earlier initiation of screening tests for family members. However, the lack of such information in medical records is a known limitation of retrospective studies like this one.
Women who met the criteria for genetic testing for pathogenic variants in the BRCA1 and BRCA2 genes were less likely to have been submitted to previous screening tests, possibly because these women were significantly younger than those without indication for testing, consistent with the Ministry of Health primary healthcare network recommendations, which advise screening tests only after 50 years of age. This also explains why women with indication were more likely to have been diagnosed through symptoms of the disease rather than through screening tests, in contrast to those without indication for testing.
The prevalence of comorbidities at the time of cancer diagnosis was significantly lower among women who met the criteria for genetic testing for pathogenic variants in the BRCA1 and BRCA2 genes when compared to those without indication for testing, particularly concerning systemic arterial hypertension (SAH). This finding concurs with Bluethmann et al29 which found that the incidence of comorbidities increases with age. This may be explained by the fact that women with indication for genetic testing were diagnosed at an earlier age compared to those without indication.
The study found a statistically significant difference in the molecular subtype of the tumor as assessed by protein expression in immunohistochemistry, similar to the study by Borges et al27. Specifically, the diagnosis of triple-negative tumors was more common among women who met the criteria for genetic testing for pathogenic variants in the BRCA1 and BRCA2 genes when compared to those without indication for testing, and there were fewer tumors of the luminal subtype (22.7% versus 4% and 59.8% versus 75%). Subsequently, there was no difference between the groups in terms of histological type and tumor grade (p = 0.836 and 0.248, respectively).
Previous studies by Alemar et al14 and Lourenção et al15 estimate that 17 to 22 women diagnosed with breast cancer during this period are unaware of their carrier status for germline mutations in the BRCA1 and BRCA2 genes because of poor access to genetic testing at SUS. Given the high risk of new primary tumor incidence in both ipsilateral and contralateral breast6,7 and ovarian tumors8, knowledge of the carrier status of pathogenic variants in these genes is crucial for the discussion of risk reduction surgeries, such as contralateral mastectomy and bilateral prophylactic salpingoophorectomy, which have been shown to effectively reduce the incidence of new cases of breast cancer (ipsilateral and contralateral) and ovarian cancer in these women9-12.
Additionally, identifying a patient who carries a pathogenic variant in the BRCA1 and BRCA2 genes allows the identification of other family members who also carry the variant and offers them the opportunity for therapies to reduce their risk of developing cancer13. A study by Lourenção et al15 demonstrated that the strategy of genetic testing for pathogenic variants in the BRCA1 and BRCA2 genes, followed by preventive strategies such as risk-reducing surgeries (prophylactic bilateral mastectomy and salpingoophorectomy) proved to be cost-effective in the context of SUS, resulting in more quality-adjusted life years (QALYs) and with an incremental cost-effectiveness ratio of R$11,900.31 (U$5,504.31)/QALY.
Based on the NCCN criteria for indication of genetic testing for mutations in the BRCA1 and BRCA2 genes, it was found that 40% of patients consulted at a UNACON in a reference hospital in Rio Grande do Sul met the criteria for genetic testing at the time of their breast cancer diagnosis but were unable to access the test because of its unavailability at SUS. It is estimated that a significant number of these patients are carriers of pathogenic variants in the BRCA1 and BRCA2 genes without being aware of the condition, and thus they are not offered therapies that could reduce the risk of developing new neoplasms.
CONCLUSION
A significant number of SUS patients consulted at a reference oncology center in the state of Rio Grande do Sul met the criteria for genetic testing to detect pathogenic variants in the BRCA1 and BRCA2 genes per the NCCN guidelines. Given that this testing is a cost-effective strategy for SUS, changes must be made to the current public health policies to ensure that patients diagnosed with breast cancer receive the best possible care.
CONTRIBUTIONS
All the authors contributed substantially to the study design, acquisition, analysis and interpretation of the data, wording and critical review. They approved the final version to be published.
DECLARATION OF CONFLICT OF INTERESTS
There is no conflict of interests to declare.
FUNDING SOURCES
Universidade do Vale do Taquari (Univates).
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Recebido em 14/7/2023
Aprovado em 21/9/2023
Scientific-Editor: Anke Bergmann. Orcid iD: https://orcid.org/0000-0002-1972-8777
Este é um artigo publicado em acesso aberto (Open Access) sob a licença Creative Commons Attribution, que permite uso, distribuição e reprodução em qualquer meio, sem restrições, desde que o trabalho original seja corretamente citado.
©2019 Revista Brasileira de Cancerologia | Instituto Nacional de Câncer | Ministério da Saúde