Long-term outcome of reoperations for medullary thyroid carcinoma

Most patients with medullary thyroid carcinoma (MTC) have persistent disease after primary surgery, as evidenced by calcitonin elevation. Previous reports showed that reoperation on selected patients yields immediate calcitonin normalization in one-third of patients. Long-term follow-up data are needed to assess the outcome in such patients. This report aims to provide 8- to 10-year follow-up on reoperations for persistent or recurrent MTC.

An Internal Review Board (IRB) approved database on patients treated for MTC has been prospectively maintained. This database was reviewed to report follow-up data on calcitonin levels and survival.

Between 1992 and 2006, 148 patients underwent reoperations for recurrent or persistent MTC (55 patients had 59 reoperations for palliation, and 93 patients had 105 reoperations for cure). Of the 93 patients operated on for cure (44 with hereditary MTC, 49 with the sporadic form), 8-10-year follow-up data were available on 56. Four patients died of disease (4.3% of 93). Two died of unrelated causes, and were excluded from calcitonin outcome analysis. Fourteen patients of 54 (26.0%) have unstimulated calcitonin levels of <10 pg/ml at 8-10 years. Eleven additional patients (20.4%) have levels<100 pg/ml. None of these 25 patients (46.4%) have radiologic recurrence.

Previous reports demonstrated the low morbidity of reoperation for MTC in experienced hands, and success was determined by lowering of calcitonin levels. Follow-up data demonstrate that at least one third of such patients have long-term eradication of their disease following reoperation, as evidenced by biochemical and imaging studies.