Differentiated Thyroid Carcinoma: Distant Metastasis as an Unusual Sole Initial Manifestation

Abstract
Objective: The objective of this study was to identify the characteristic features of patients with distant metastasis as the only manifestation of well-differentiated thyroid cancers and to analyze the treatment outcomes. Methods: A retrospective review of all patients with well-differentiated thyroid cancers and distant metastasis as the sole initial presentation was carried out. Data regarding age, gender, tumor histology, site, symptoms, and treatment outcomes were collected. Results: There were 10 patients who presented with distant metastasis as the only presentation.The mean age was 56.1 years. Eight (80%) patients had osseous metastasis, one (10%) had pulmonary and one (10%) had both. Follicular thyroid carcinoma was more common and seen in six (60%) patients. Seven (77.8%) out of nine patients had demised within five years of initial presentation. Conclusion: Distant metastases without a neck lump as the initial presentation of well-differentiated thyroid cancers are extremely rare. No specific guidelines are available to manage such patients due to lack of relevant data in the literature.