Clinical outcomes in older adults with advanced thyroid cancer

BACKGROUND: Age is a prognostic factor in thyroid cancer. However, little is known about benefits and risks of systemic therapy in older adults with advanced thyroid cancer. PATIENTS AND METHODS: We performed a retrospective review of patients ≥ 65 years of age with advanced thyroid cancer referred to medical oncology at our institution for consideration of systemic therapy between 2010-2025 (n = 114). Clinicopathologic, treatment, adverse event, and outcomes data were analyzed. RESULTS: 65/114 patients received first-line systemic therapy. Median overall survival (OS) was 4.04 years (95% CI 3.09-not estimable) in the whole cohort and 3.91 years (95% CI 2.84-not estimable) in the treated cohort. First-line time-to-treatment discontinuation (TTD) in the treated cohort was 1.59 years (95% CI 0.75-4.45). Age, male sex, and anaplastic histology predicted shorter OS in the whole cohort. Age, male sex, increasing Charlson comorbidity index, and BRAF and/or TERT mutation predicted worse OS and/or TTD amongst treated patients. For patients receiving lenvatinib (n = 37), adverse events led to significant proportions of patients requiring dose reductions (65%), treatment breaks (78%), emergency department (ED) visits (16%), and drug discontinuation (14%). Adverse events led to treatment breaks (56%), ED visits (67%), and drug discontinuation (22%) in patients receiving dabrafenib + trametinib (n = 9). Female sex, geriatric oncology referral, polypharmacy, and BRAF mutation predicted higher number of ED visits. CONCLUSION: Although survival outcomes were comparable to those described in younger adults, adverse events were common and impactful in older adults.