e18135 Background: Anaplastic thyroid carcinoma (ATC) is a rare and highly aggressive malignancy with limited treatment options and poor survival outcomes. Real-world data on systemic therapies, including targeted treatments and chemotherapy, remain limited. Methods: This retrospective analysis included 10 patients with ATC treated at a tertiary cancer center between 2019 and 2025. Five patients received dabrafenib/trametinib and five received chemotherapy as first-line systemic therapy (cisplatin–doxorubicin, n=3; paclitaxel–carboplatin, n=2). Clinical characteristics, treatment response, progression-free survival (PFS), and overall survival (OS) were evaluated using the Kaplan–Meier method. Results: The median age was 60 years (IQR: 54.7–67.7), and 50% of patients were male. At diagnosis, 10% had stage IVB disease and 90% had stage IVC disease. Primary tumor resection was performed in 60% of patients. The most common metastatic sites were lymph nodes (80%) and lungs (30%). BRAF mutations were identified in 50% of patients, and the median PD-L1 expression was 22.5% (IQR: 10.5–27.5) (Table 1). Objective responses were observed in three patients in the chemotherapy group and two in the dabrafenib/trametinib group. Disease control was achieved in four and five patients, respectively. The median follow-up duration was 11.9 months (IQR: 3.7–12.1). In both treatment groups, three patients died and four experienced disease progression. The median PFS in the overall cohort was 5.7 months (95% CI: 5.2–6.2). Median PFS was 5.1 months (95% CI: 3.0–7.1) with chemotherapy and 5.7 months (95% CI: 4.5–6.9) with dabrafenib/trametinib (p = 0.06). The median OS was 11.9 months (95% CI: 6.5–17.3) overall, 7.7 months (95% CI: 6.5–8.9) with dabrafenib/trametinib, and 12.6 months (95% CI: 0–26.0) with chemotherapy (p = 0.23). Conclusions: Systemic therapies provided limited but clinically relevant benefit in patients with anaplastic thyroid carcinoma. Nevertheless, survival outcomes remained poor, highlighting the need for improved therapeutic strategies for this aggressive disease. Baseline demographic and clinical characteristics of patients with anaplastic thyroid carcinoma. Variable Patients n=10 Age, median (IQR) 60 (54.7–67.7) Age ≥65 years 4 (40%) Female 5 (50%) Male 5 (50%) Stage IVB 1 (10%) Stage IVC 9 (90%) Primary tumor resection 6 (60%) Primary tumor radiotherapy 2 (20%) Palliative radiotherapy 9 (90%) Bone metastasis 3 (30%) Lymph node metastasis 8 (80%) Lung metastasis 4 (30%) Liver metastasis 1 (10%) Other metastasis 1 (10%) No driver mutation 5 (50%) BRAF mutation 5 (50%) PD-L1 expression, median (IQR) 22.5 (10.5–27.5) Dabrafenib/Trametinib 5 (50%) Chemotherapy 5 (50%) Progression 8 (80%) Death 6 (60%) Data are presented as n (%) or median (IQR). Abbreviations: ATC, anaplastic thyroid carcinoma; ChT, Chemotherapy; IQR, interquartile range.
Alan et al. (Thu,) studied this question.