Evaluating the Prognostic Factors Associated with Cancer-specific Survival of Differentiated Thyroid Carcinoma Presenting with Distant Metastasis

Abstract

BackgroundBecause patients with differentiated thyroid carcinoma (DTC) presenting with distant metastasis (DM) have a particularly poor prognosis, examining the prognostic factors in this group is essential. We aimed to evaluate the prognostic factors affecting cancer-specific survival (CSS) in DTC patients presenting with DM.MethodsOf the 1227 DTC patients, 51 (4.2 %) presented with DM at diagnosis. All patients underwent a total thyroidectomy, followed by radioiodine (RAI) ablation and postablation whole body scan (WBS). Patients were considered to have an osseous metastasis if one of the metastatic sites involved a bone, while RAI avidity was determined by any visual uptake in a known metastatic site on the first WBS. Factors predictive of CSS were determined by univariate and multivariate analyses by the Cox proportional hazard model.ResultsIn univariate analysis, older age (relative risk [RR] 1.050, 95 % confidence interval [CI] 1.010–1.091, P = 0.014), DM discovered before WBS (RR 3.401, 95 % CI 1.127–10.309, P = 0.030), follicular thyroid carcinoma (RR 3.095, 95 % CI 1.168–8.205, P = 0.025), osseous metastasis (RR 4.695, 95 % CI 1.379–15.873, P = 0.013), non-RAI avidity (RR 3.355, 95 % CI 1.280–8.772, P = 0.014), and external beam radiotherapy to DM (RR 3.241, 95 % CI 1.093–9.614, P = 0.034) were significant poor prognostic factors for CSS. In the multivariate analysis, after adjusting for other factors, osseous metastasis (RR 6.849, 95 % CI 1.495–31.250, P = 0.013) and non-RAI avidity (RR 7.752, 95 % CI 2.198–27.027, P = 0.001) were the two independent poor prognostic factors for CSS. Older age almost reached statistically significance (RR 1.055, 95 % CI 0.996–1.117, P = 0.068).ConclusionsDTC patients presenting with DM accounted for 4.2 % of all patients. Because osseous metastasis and RAI avidity were independent prognostic factors, future therapy should be directed at improving the treatment efficacy of osseous and/or non-RAI-avid metastases.

Follicular thyroid carcinoma with distant metastasis: outcome and prognostic factor

“…Dedifferentiation of thyroid cancer may be related to poorer outcome and iodine avidity is thought to be one of the indicators of thyroid tumor differentiation. Several papers have reported finding a significant relationship between iodine avidity and the outcome of DTC patients with DM [10,11,12,13]. But we could not show iodine avidity was not related to age sis.…”

Patterns of metastasis in follicular thyroid carcinoma and the difference between early and delayed presentation

“…1,19 Resecting the osseous metastasis where possible using an aggressive surgical approach may improve survival in cases with FTC. 20 In our study, all patients with osseous involvement underwent excision and stabilisation, which probably explains the improved survival.…”

Pulmonary metastases in differentiated thyroid cancer: efficacy of radioiodine therapy and prognostic factors

“…Distant metastases are an uncommon event in DTC and a wide range in prevalence (4-23%) has been reported (1,2,3,4,5,6). Lungs are the most frequent site of distant metastasis in DTC and the resulting respiratory failure may be the most common cause of death.…”