Prognostic factors in well-differentiated thyroid carcinoma in patients treated and followed in the same institution.

AIM: To test the prognostic significant of clinicopathologic factors in patients affected by well-differentiated thyroid carcinoma (WDTC).

METHODS: A retrospective review of patients treated for WDTC (thyroidectomy and a radioactive iodine (1131) thyroid ablation) at our Institute with a minimum of 10 years of follow-up was carried out. The unfavourable prognosis at the end of the follow-up was defined as persistence/recurrence of WDTC or death due to the cancer.

RESULTS: 234 patients (162 female, 72 male), mean age of 47.6 +/- 166 years, were included in this study (mean follow-up 158.4 +/- 34.8 months): 78 (33.4%) subjects had persistence/recurrence of neoplasia while 5 (2.1%) died for cancer. The multivariate regression showed that prognostic factors were old age, size of cancer, detectable thyroglonulin levels six months after metabolic ablation, and DeGroot staging system.

DISCUSSION: Our mortality rate is lower (2.1%) than reported in literature (10%): this could be explained by the different pathological classification and treatment. The mortality rate appears higher in patients treated with emitiroidectomy and TSH suppressive therapy than in those with total thyroidectomy and I131 ablation. Even if we have chosen an "aggressive" therapy and our mortality rate is lower, one third of patients have persistence/recurrence of cancer: it seems that tumour recurrence rate better reflects clinical problems related to cancer.

CONCLUSION: WDTC has with a good disease-specific survival but a significant recurrence rate. The most important predictors are the old age and the size of lesion. We suggest a radical surgery followed by radiometabolic ablation in all patients with WDTC.