Postoperative biochemical remission of serum calcitonin is the best predictive factor for recurrence-free survival of medullary thyroid cancer: a large-scale retrospective analysis over 30 years.

SummaryContext The increase in thyroid screening in the general population may lead to earlier detection of medullary thyroid carcinoma (MTC). Objective We aimed to evaluate secular trends in clinicopathological characteristics and long-term prognosis of MTC and its prognostic factors. Design This was a retrospective analysis from 1982 to 2012. Patients Three hundred and thirty-one patients with MTC were included and grouped based on the year of diagnosis (1982–2000, 2001–2005, 2006–2010 and 2011–2012). Measurements These included recurrence and mortality as well as biochemical remission (BCR) of serum calcitonin. Results Mean tumour size (from 2·5 cm to 1·7 cm, P  2 cm (HR = 18·33, 95% CI 2·35–143·06; P = 0·006) and distant metastasis (HR = 4·00, 95% CI 1·31–12·21; P = 0·015) were significant prognostic factors for mortality. Conclusions Clinicopathological characteristics and recurrence of MTC improved with time. Po-BCR was the best predictive factor for recurrence-free survival.