Endocrine Abstracts

Thyroid differentiated carcinomas are of good prognosis except in case of metastatic dissemination. These distant metastasis, especially the bone one, are a major cause of altered quality of life and death. This study concerns a cohort of 21 patients treated from 1995 to 2011.The aim of our work is to study the characteristics of patients who had bone metastases in association with thyroid cancer to determine their prognostic factors. 18 of our patients were over 45 years of age with a majority of vesicular carcinoma (81%). Distribution of patients according to the anatomopathological characteristics of the tumor were: multifocality 28.6%, thyroid capsule invasion 52.2%, complete lymph node chain resection 66.7%. Bone metastases are often multiple. They are located in order of decreasing frequency: limbs 76%, spine 46%, skull 38%, pelvis 33.3% and sternum 28.5%. They have been associated with other types of metastasis, especially pulmonary metastases (13 patients) and brain (2 patients). The mean stimulated thyroglobulin (sTg) level before radioactive iodine therapy was 762.95 ± 484.64 ng/ml with extremes from 3 to 2000 ng/ml. The average number of radioactive iodine therapy (RIT) cures received by patients was 9 ± 8.25. Consequently, bone metastases fixing iodine was noticed for 20 patients. (RIT) had as a result the disappearance of bone uptake in 1 case, reduction in 2, and stabilization in 9. More intensive uptake was noted in 7 cases. Thus, the (sTg) level was declining for 4 patients, stable for 5 and rising for 12 patients. In addition, radiotherapy of bone metastatic sites was performed for 10 patients and Only 4 patients (19%) had metastases removal surgery. The 5-year survival was 74% for patients who have had radiotherapy. After an average delay of 6.4 years from time carcinoma firstly diagnosed and 3.4 years its bone metastases: a partial remission was notable for only 1 patient, a stationary state was observed for 9 patients and clinical aggravation was observed for 11 patients. Overall survival was 65% at 5 years and 49% at 10 years. With a multidisciplinary treatment adapted to each case, it was possible to obtain long survival in 10% of cases.

Conclusion

The treatment of bone metastasis in association with thyroid cancer represents a difficult challenge requiring, as a result, more extensive treatment.