Prevalence of germline testing criteria in breast cancer patients in the Brazilian public health system: A retrospective study.

Abstract

10597 Background: Identification of a germline mutation in a breast cancer predisposition gene has implications for the patients and their families. The National Comprehensive Cancer Network (NCCN) has published guidelines for genetic testing. In Brazil, this assessment is covered by health insurance in accordance with criteria defined by the National Supplementary Health Agency (ANS). For the majority of the population, served by the public health system (SUS), the assessment is not routinely available. Methods: In order to determine the prevalence rates of NCCN and ANS criteria for germline testing in breast cancer (primary outcome) we retrospectively analyzed data from patients treated at two SUS oncology centers in Belo Horizonte, Minas Gerais, Brazil, between 01/01/18 and 12/31/19. The secondary outcomes were comparisons between the groups with and without germline testing criteria (NCCN and ANS) regarding overall survival, clinical and epidemiological characteristics. The association between qualitative variables was calculated using the Chi-square and Fisher tests. The Kaplan-Meier method was used to analyse the survival data and the differences between the groups were tested using the log-rank test. The level of significance was 5%. Results: A total of 357 patients were included in the final analysis. The presence of germline testing criteria were found in 126 patients (35%) according to NCCN guidelines and in 82 patients (23%) according to ANS guidelines. None of them were tested for germline mutations. The most common criteria were women up to 60 years old with triple negative tumors (n = 43, 12% of all patients) and diagnosis of cancer up to 45 years old (n = 75, 21% of all patients) according to ANS and NCCN criteria, respectively. When the group of patients who met at least one criterion for germline testing were compared with the group who did not met any criteria, we found in the first group: more ductal carcinomas and less lobular tumors (p = 0.009), more grade 3 tumors (p = 0.002), more triple negative tumors (p < 0.001), more neoadjuvant treatments (p = 0.008) and less hormonal therapies (p = 0.011). After a median follow up of 13.5 months there were 22 deaths in the cohort, 7 in the group with testing criteria (5.7%) and 15 in the group without testing criteria (6.4%). There was no statistical significant difference between the groups in terms of overall survival (p = 0.77). Conclusions: To our knowledge this is the first study to evaluate the prevalence of NCCN and ANS criteria for germline testing in patients with breast cancer treated in the Brazilian public health system. Our results show that more than a third of those patients are candidates for germline testing. Moreover, the data highlight a serious shortcoming in the management of breast cancer and must be considered in the development of public health policies for routine germline testing in that population.