Introduction
Medullary thyroid cancer (MTC) is an aggressive subtype of thyroid malignancy. While the incidence of differentiated thyroid cancer (DTC) has been increasing globally, trends in the incidence and prognosis of MTC are less clear. The objective of this study is to analyse the incidence, management and survival of patients with MTC in the Irish population.
Methods
A retrospective analysis of patients diagnosed with MTC between 1994-2019 was performed using the Irish National Cancer Registry (NCRI). Comparisons were made between patients diagnosed between 1994-2007 and 2008-2019. Kaplan-Meier survival analysis was used to determine the overall and disease-specific survival. Univariate and multivariate Cox regression analysed factors predictive of outcome.
Results
A total of 152 patients were diagnosed with MTC. Median age was 53 years. 53.3% of patients were male and 46.7% were female. Five-year overall and disease-specific survival were 67% and 73.2% respectively. On multivariate regression, the only significant predictors of both overall survival (OS) & disease specific survival (DSS) were surgical management (HR 0.18, p=0.013) and chemotherapy (HR 4.29, p=0.014).
Conclusion
This review presents changing trends in the incidence, management and survival of patients with medullary thyroid cancer over a 25 year period in Ireland. A trend towards improved overall survival is noted in patients diagnosed in the later cohort.