The Manchester Scoring System for predicting BRCA1/2 mutations underperforms in Arabic Omani breast cancer patients

Risk assessment models that are applied to assess the lifetime risk of cancer and pathogenic variant risk are more commonly used in Western populations. Using these models, without validation, for non-Western populations has been questioned. This study aimed to evaluate the use and consistency of the Manchester Scoring System as a risk assessment model for the Omani population. A retrospective, file-based analysis was performed on breast cancer patients seen in a genomics department over a two-year period. Personal cancer history and family history were used to analyze the Manchester scores of 409 breast and/or cancer patients. The results show that, overall, the Manchester scores were low. If this risk assessment model had been used to determine eligibility for a priori service and genetic testing decisions, 12 BRCA pathogenic cases would have been missed. At this time, the Manchester Scoring System does not seem to be the best risk assessment model for use in the Omani population, unless the eligibility threshold of ≥6 is used, which could provide a better sensitivity for the Omani population. We propose using concepts of the Manchester Scoring model to create a scoring system that is more suitable for the Omani and Arabic population.