ETA2024 Oral Presentations Oral Session 12: Clinical thyroid cancer research (7 abstracts)
1Gustave Roussy, Service Doncologie Endocrinienne/Endocrine Oncology Unit, Villejuif, France; 2University Lyon I. Endocan Tuthyref, Endocrinology Department-Inserm, U 1052, Lyon, France; 3Institut Bergonié. Endocan Tuthyref, Department of Nuclear Medicine and Thyroid Oncology, Bordeaux, France; 4University Hospital of Lille, Endocan Tuthyref, Department of Endocrinology and Metabolism, Lille, France; 5Chu de Nantes-Hopital Laennec Saint-Herblain, Endocan Tuthyref, Endocrine Department, Linstitut du Thorax, Nantes, France; 6Institut Curie, Endocan Tuthyref, Département de Médecine Nucléaire, St Cloud, France; 7Grenoble Alpes University Hospital, Endocan Tuthyref, Department of Oncology, Grenoble, France; 8Pitié-Salpêtrière Hospital, Paris Vi University, Cancer Institute, Endocan Tuthyref, Department of Nuclear Medicine, Paris, France; 9Chu La Cavale Blanche, Endocan Tuthyref, Endocrine Department, Brest, France; 10Chu Angers, Endocan Tuthyref, Department of Endocrinology, France, France; 11University Lyon I, Endocan Tuthyref, Endocrinology Department-Inserm, U 1052, Lyon, France; 12Gustave Roussy, Université Paris-Saclay, Département de Biostatistique et Épidémiologie, Villejuif, France; 13Service Doncologie Endocrinienne/Endocrine Oncology Unit, Gustave Roussy, Endocan Tuthyref, Département Dimagerie, Villejuif, France; 14Gustave Roussy, Université Paris-Saclay, Endocan Tuthyref, Département de Biostatistique et Épidémiologie, Villejuif, France; 15Pitié-Salpêtrière Hospital, Paris Vi University, Cancer Institute, Endocan Tuthyref, Department of Nuclear Medicine, Thyroid and Endocrine Tumors Unit, Paris, France; 16Service Doncologie Endocrinienne/Endocrine Oncology Unit, Gustave Roussy,Endocan Tuthyref, Département Dimagerie, Villejuif, France
Background: Radioiodine-refractory differentiated thyroid cancer (RAI-R DTC) patients with distant metastases show poor survival rates. However, patients outcome can be very heterogeneous, with cases spanning from microscopic slowly growing metastases to symptomatic, rapidly progressive disease. The aim of this study was to assess the overall survival (OS) of RAI-R DTC patients with distant metastases and to identify the prognostic factors associated with OS.
Patients and methods: A retrospective analysis of consecutive cases of distant metastatic RAI-R DTC, diagnosed between 1990 and 2022 in 10 referral centers in France, was performed. Survival was estimated using the Kaplan-Meier method and the associated prognostic factors were assessed by Coxs model.
Results: The study cohort included 899 patients: 52.1% females, with a median age of 65 years (range:20-90) at RAI-R DTC diagnosis. The median follow-up was 4.8 years (range:0.1-40.1) and almost all patients (95.9%) underwent primary tumour resection. Thyroid tumors were papillary in 55.6%, follicular in 12.2%, oncocytic in 10.6% and poorly differentiated in 21.6% of the patients. Metastases were synchronous to primary diagnosis in 325 (39.4%), macroscopic (>1 cm) in 425 (48.2%) and multiple organs were involved in 83.4% of the cases. The most represented distant metastatic sites were the lung (84.3%), mediastinal lymph nodes (48.1%) and bone (46.8%). In a subgroup of 332 patients (37%) driver mutation status was assessed: 63% BRAFV600E mutation, 29.5% RAS mutation (NRAS 21%, HRAS 5%, KRAS 3.5%) and 6% gene fusions (involving RET (3%), NTRK (2%) and ALK (1%). More than half of the patients (58%) were treated with systemic therapies at some point during the follow-up. After the diagnosis of RAI-R DTC, median OS was 9.5 years the 5- and 10-year OS rates were 74.8% and 48.1%, respectively. In multivariate analysis, some factors were associated with a poorest survival: age ≥55 years (Hazard-ratio (HR)=2.54 95%CI 1.84-3.57), multiple metastatic sites (Hr = 2.80 95%CI 1.80-4.64), macroscopic metastatic volume (Hr = 1.98 95%CI 1.54-2.55), presence of 18FDG-PET uptake (Hr = 2.08 95%CI 1.30-3.52), whereas primary tumor resection (Hr = 0.50 95%CI 0.31-0.86), differentiated tumor type (Hr = 0.53 95%CI 0.41-0.68) and metachronous metastatic presentation (Hr = 0.64 95%CI 0.50-0.82) were associated with a longer OS.
Conclusions: The independent clinical, histological and radiological prognostic factors identified can stratify the OS of RAI-R DTC patients and support clinical decisions in this challenging context.