Development and Evaluation of a Web-Based Outcome Database for Advanced Melanoma with Rare BRAF Mutations.

Rare B-rapidly accelerated fibrosarcoma gene (BRAF) mutations in advanced melanoma, and other malignancies, represent a significant clinical challenge due to sparse evidence on the efficiency of targeted therapy. Conventional genomic databases do not integrate detailed outcome data on treatments for patients with these mutations, requiring innovative informatics approaches.For the use case of patients with rare BRAF-mutated melanoma, we developed a "Treatment Outcome Tool" as a web-based database on rare cancers that aggregates anonymized, expert-validated clinical data. Unstructured interviews with dermato-oncologic experts guided the design, ensuring that the system allows users to query specific or combined rare BRAF mutations and retrieve key outcome measures, such as progression-free survival, overall response rate, and disease control rate with BRAF and/or mitogen-activated proteinkinase kinase (MEK) inhibition. Data are collected via a structured input form. After rigorous review and quality assurance by dedicated experts, data are then transferred to an externally accessible R/Shiny platform, where they can be assessed. The usability of the developed database was then evaluated by the System Usability Scale (SUS) of contributing dermato-oncologic experts.The first productive database version was implemented in October 2024. As of May 2025, the database contained data from 130 patients with 23 BRAF mutations. Evaluation of the "Treatment Outcome Tool" by 14 international dermato-oncologic experts yielded a median SUS score of 92.5, confirming excellent usability.Our database fills a critical gap in personalized oncology therapy by directly correlating rare BRAF mutation profiles with treatment outcomes. Our tool had usability and was found to be of high clinical value. The generic informatics framework chosen by us has the potential to be expanded to other rare tumors, ultimately enhancing evidence-based clinical practice and fostering international collaboration in cancer research.