Factors related to the survival of papillary and follicular thyroid carcinoma patients with distant metastases

There is limited clinical information comparing presentations and results o f treatment of papillary and follicular thyroid carcinoma patients with dis tant metastases. We retrospectively analyzed data of 1257 thyroid cancer pa tients who received their treatment and follow-up at Chang Gung Memorial Ho spital. We found 992 patients with papillary carcinoma and 205 patients wit h follicular thyroid carcinoma. Of these, 68 patients with papillary thyroi d carcinoma (6.9%) had distant metastases at the time of diagnosis or durin g the follow-up period. Of the follicular thyroid carcinoma patients, 69 (3 3.7%) had distant metastases, Of the 68 patients with papillary carcinoma, only 33 were categorized as stage IV at the time of diagnosis. Nine of the patients were categorized as clinical stage I carcinoma, 10 as stage II, an d 16 as stage III. Sixteen patients (23.5%) died during the study period, a ll but 2 of thyroid cancer. Twelve of the 68 patients were disease-free aft er treatment. Of the 69 patients with follicular thyroid carcinoma, 58 were categorized as stage IV at the time of diagnosis. Six of the patients were categorized as clinical stage I carcinoma, 2 as stage II, and 3 as stage I II at the time of diagnosis; all of these patients deteriorated to stage IV during the follow-up period. Of the 42 patients with follicular thyroid ca rcinoma involving bone, 24 presented with bone metastases during the initia l diagnosis. After treatment, 25 of 69 patients with follicular carcinoma d ied of follicular carcinoma. Only 3 patients were disease-free after the tr eatment. In patients with follicular carcinoma, only tumor size was an impo rtant prognostic factor. In this study, 8 patients categorized as clinical stages I to III at the time of operation had thyroglobulin (Tg) levels less than 5 ng/mL and developed distant metastases during the follow-up period. In conclusion, at diagnosis a large group of Asian patients with metastati c well-differentiated thyroid cancer was more likely to have follicular tha n papillary histology, and that, as expected, metastases from follicular ca ncer were present earlier and more frequently, were more likely to involve bone, were more likely to be associated with mortality, and were linked to tumor size but not gender. Also unlike some other reports, treatment produc ing a low Tg did not always produce a good outcome. More aggressive surgica l procedures may be able to improve outcomes.