1936P - Treatment outcomes of patients with anaplastic thyroid carcinoma (atc): Multicentric data from spanish national registry (regetne-tiroides)

Background

Anaplastic thyroid carcinoma (ATC) is a rare and highly aggressive malignancy with a poor prognosis. Conventional chemotherapy (CT) in the metastatic setting has demonstrated limited efficacy and significant toxicity. However, the landscape of ATC management is rapidly changing, with emerging therapeutic options such as immunotherapy (IO) and targeted therapy (TT) driven by improved molecular profiling and identification of actionable targets, offering potential to alter the course of this disease.

Methods

Retrospective descriptive multicenter analysis of patients (pts) diagnosed with ATC between 2000-2024 across 9 hospitals in Spain using data from the REGETNE registry. Baseline demographic and clinical characteristics, molecular profiling, type of systemic treatment, treatment sequence and overall survival (OS) were analyzed.

Results

95 pts (mean age: 67 years, 54% female) were included. At diagnosis, 7.4% were stage IVA, 38.9% IVB, and 52.6% IVC. The most common sites of metastasis at diagnosis were lung (32.6%), non-regional lymph nodes (20%), bone (4.2%), and liver (2.1%), with one patient having brain involvement. Next-generation sequencing (NGS) was performed in 61% of pts, revealing frequent alterations including BRAF (17.9%), P53 (12.6%), PAX8 (9.4%), NRAS (4.2%), TERT (3.2%), KRAS (1.1%) and other mutations such as ALK rearrangement (2.1%), PI3K (2.1%), PTEN (1%), and MET fusion (1%). There were no RET mutations reported. 74.7% of patients received systemic therapy. 13.7% received multikinase inhibitors (MKI) and IO at some point during their disease course. Notably, 41.1% of patients with BRAF mutations received TT. First-line systemic treatment consisted of CT (69%), clinical trials (12.6%), MKI (7%), and TT or IO (5.6% each), whereas 2^nd line treatment (received by 33.68% of pts) consisted of CT (34.3%), clinical trials (31.2%), IO (12.5%), and TT or MKI (9.3% each). Only 15.8% and 1.1% of patients reached a 3^rd or 4^th line of treatment, respectively. After a median follow-up of 6.9 months (0-180.8m) median OS was 8.6m (95% CI 5.9m-11.4m).

Conclusions

Despite BRAF TT options in ATC, median OS is still very poor. New therapeutic options are urgently needed in this population.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

GETNE.

Funding

Has not received any funding.

Disclosure

J. Hernando Cubero: Financial Interests, Personal, Advisory Board: Eisai, Ipsen, Novartis, AAA, Angelini, Pfizer, Roche. A. Garcia Alvarez: Financial Interests, Personal, Advisory Board: ADACAP (Novartis); Other, Other, Expenses (Travel, Congress inscription): Advanz, Eisai, Ipsen, ADACAP (Novartis). I. Ceballos Lenza: Financial Interests, Personal, Invited Speaker: Pfizer, Novartis, Merck, MSD, BMS, Roche, AstraZeneca; Financial Interests, Personal, Advisory Board: Seagen, Novartis; Non-Financial Interests, Principal Investigator: BMS, GSK. M. Plana Serrahima: Financial Interests, Personal, Invited Speaker, X: MSD; Financial Interests, Personal, Invited Speaker: Eisai. E. Gallardo: Financial Interests, Personal, Advisory Board: Sanofi, Janssen, Astellas, Pfizer, Bayer, Roche, Ipsen, Eisai, EUSA Pharma, BMS, AstraZeneca, Merck, Merck, Daiichi Sankyo, Techdow, Novartis, Lilly, Pfizer, Advanced Accelerator Applications, GSK, Recordati; Financial Interests, Personal, Invited Speaker: Sanofi, Janssen, Astellas, Pfizer, Bayer, Roche, Ipsen, Eisai, EUSA Pharma, BMS, Merck, Daiichi Sankyo, MSD, Menarini, Rovi, Leo Pharma, Boehringer Ingelheim, Advanced Accelerator Applications; Financial Interests, Institutional, Local PI: Astellas, Medivation, Ipsen, Janssen, Pfizer, Lilly, Pfizer-Merck, MSD, BMS, Bayer, Daiichi Sankyo, Roche, AstraZeneca, Novartis, Seattle Genetics, Incyte, Aveo, Exelixis, Immunicum, Mediolanum, Clovis, QED Therapeutics, Debiopharm, Macrogenics; Non-Financial Interests, Principal Investigator, National (Spanish) coordinator for clinical trials: Anthos; Non-Financial Interests, Leadership Role, Member of the Board: SOGUG; Non-Financial Interests, Leadership Role, Member of the Board of Long Survivors Working Group: SEOM. J. Capdevila Castillon: Financial Interests, Personal, Invited Speaker: Novartis, Pfizer, Ipsen, Exelixis, Bayer, Eisai, Advanced Accelerator Applications, Amgen, Sanofi, Lilly, Merck Serono; Financial Interests, Personal, Advisory Board: Pfizer, Ipsen, Exelixis, Bayer, Eisai, Advanced Accelerator Applications, Amgen, Sanofi, Lilly, Merck Serono, Esteve, ITM; Financial Interests, Personal, Research Grant: AstraZeneca, Advanced Accelerator Applications, Bayer, Eisai, Novartis, Pfizer; Financial Interests, Institutional, Research Grant: Roche, Gilead; Financial Interests, Institutional, Coordinating PI: ITM, Boeringher. T. Alonso Gordoa: Financial Interests, Personal, Advisory Board: Ipsen, Pfizer, Roche, Sanofi, Bayer, Eisai, Novartis Advanced Accelerator Applications, Lilly, Bristol Myers Squibb, Astellas; Financial Interests, Personal, Invited Speaker: Janssen-Cilag; Non-Financial Interests, Project Lead: Ipsen, Pfizer, Johnson & Johnson. All other authors have declared no conflicts of interest.