RESUMEN
CONTEXT: Lenvatinib is approved for the treatment of radioiodine-refractory differentiated thyroid cancer (RR-DTC). The definition of predictive factors of survival is incomplete. OBJECTIVE: To identify pre- and post- treatment survival predictors in a real-life cohort of RR-DTC treated with lenvatinib. DESIGN: Multicenter, retrospective, cohort study. SETTING: Three Italian thyroid cancer referral centers. PARTECIPANTS: 55 RR-DTC treated with lenvatinib. MAIN OUTCOME MEASURES: Progression-free survival (PFS) and overall survival (OS). RESULTS: Lenvatinib was the first-line kinase-inhibitor in 96.4% of subjects. Median follow-up was 48 months. Median PFS and OS were 26 (95% CI 19.06-32.93) and 70 months (95% CI 36-111.99), respectively. Pre-treatment setting: Eastern Cooperative Oncology Group (ECOG) performance status was independently related to PFS (p < 0.001; HR 18.82; 95% CI 3.65-97.08: score 0-1 as reference) and OS (p = 0.001; HR 6.20; 95% CI 2.11-18.20; score 0-1 as reference); radioactive iodine (RAI)-avidity was independently related to PFS (p = 0.047; HR 3.74; 95% CI 1.01-13.76; avid disease as reference). Patients with good ECOG status (0-1) and RAI-avid disease obtained objective response in 100% of cases and achieved a median PFS of 45 months without any death upon a median follow-up of 81 months. Post-treatment setting: best radiological response independently predicted PFS (p = 0.001; HR 4.6; 95% CI 1.89-11.18; partial/complete response as reference) and OS (p = 0.013; HR 2.94; 95% CI 1.25-6.89; partial/complete response as reference). CONCLUSIONS: RR-DTC with good performance status and RAI-avid disease obtain the highest clinical benefit from lenvatinib. After treatment initiation, objective response was the only independent survival predictor.
RESUMEN
BACKGROUND: A basal serum calcitonin (Ct) increase >100 pg/mL in patients with a thyroid nodule is consistent with the diagnosis of medullary thyroid cancer (MTC). In cases where the CT test have a slight to moderate increase, the calcium gluconate stimulation test is helpful to increase diagnostic accuracy. However, reliable cut-offs for calcium-stimulated Ct are still lacking. The aim of this study was to evaluate the sex-specific calcium-stimulated Ct cutoffs for the diagnosis of MTC in a multicenter series. A comparison between different Ct assays has been also performed. METHODS: 90 subjects undergone calcium-stimulated Ct for a suspected MTC in 5 Endocrine Units between 2010-2021 were retrospectively analyzed. Serum Ct concentrations were assessed by immunoradiometric (IRMA) or chemiluminescence (CLIA) assays. RESULTS: MTC was diagnosed in 37 (41.1%) and excluded in 53 (58.9%) patients. The best calcium-stimulated Ct cut-off to identify MTC was 611 pg/mL in males (AUC =0.90, 95% CI (0.76;1) and 445 pg/mL in females (AUC=0.79, 95% CI (0.66;0.91). Logistic regression analysis showed that both basal (OR 1.01, P=0.003) and peak Ct after stimulation (OR 1.07, P=0.007) were significantly associated with MTC, together with sex (OR=0.06, P<0.001). The "Ct assay" variable was also considered in the logistic regression model, but it was not significantly associated with MTC (OR=0.93, P=0.919). CONCLUSIONS: This study indicates that calcium test could be helpful to identify patients with early-stage MTC and those without MTC. A Ct value of 611 pg/mL in males and 445 pg/mL in females are proposed as the optimal Ct cut-offs at the stimulation test.
