PRIMARY OBJECTIVE:
To evaluate the therapeutic effects, benefits, and adverse effects associated with belzutifan treatment, as well as the timing of treatment response and/or disease progression.
SECONDARY OBJECTIVES
1. To evaluate the association of host intrinsic factors with toxicity and treatment response in a Brazilian cohort of patients with von Hippel-Lindau syndrome treated with belzutifan.
2. To assess hemoglobin and erythropoietin levels during the first six months of treatment, and to document the need for subcutaneous erythropoietin supplementation in patients who develop grade 2-3 anemia, fatigue, or hypoxia.
3. To evaluate the potential impact of erythropoietin supplementation on tumor growth during belzutifan treatment.
4. To assess health-related quality of life and patient perceptions regarding VHL syndrome using validated questionnaires and instruments.
5. To conduct a pharmacoeconomic analysis in the cohort of patients with access to belzutifan, assessing its impact on healthcare costs compared to the natural history of the disease.