Clinical features of bone metastasis for differentiated thyroid carcinoma: A study of 21 patients from a Tunisian center

INTRODUCTION: The differentiated thyroid cancers have a good prognosis unless the presence of metastasis. These distant metastases, especially in bone, are a major cause of impaired quality of life and death requiring intensive management. The aim of our work was to study the patients' data, the disease characteristics and to analyze the therapeutic management of these patients. RESULTS: This study concerned a cohort of 21 patients treated for differentiated thyroid cancer during the period from 1995 to 2011. Eighteen of our patients were aged over 45 years. A majority of them had follicular carcinoma. Bone metastases were often multiple and located at the axial skeleton. They were associated with other types of metastases, especially lung metastasis. A majority of patients received 131I treatment, following surgery or external beam radiotherapy for a palliative purpose. Overall survival was 65% at 5 years and 49% at 10 years. A long-term survival was achieved in 10% of the patients benefiting from a multidisciplinary care adapted to each case. CONCLUSION: Bone metastases often have a pejorative turning in the natural history of differentiated thyroid cancers. The right selection of individuals with better prognosis, for whom more aggressive curative treatment was indicated, requires a better understanding of the features of bone involvement.