Survival in patients with medullary thyroid cancer after less than the recommended initial operation

Abstract

Background and objectives: We aimed to evaluate the disease specific-survival (DSS) of patients with Medullary Thyroid Cancer (MTC) confined to the central neck based on the extent of the initial operation.

Methods: This retrospective review of patients with MTC from the SEER registry from 2004 to 2012 excluded patients with lateral neck involvement or distant metastases.

Results: The cohort (n = 766) included 85(11%) less than total thyroidectomies (TT), 212(28%) TT alone, and 469(61%) TT with lymph node excision. Mean tumor size was similar (2.2cm for <TT, 1.9 for TT alone, and 2.2 for TT with nodes, p=0.13). Patients receiving a TT with nodal excision were more likely to have multifocal tumors (8% <TT, 22% TT alone, and 27% TT with nodes, P < 0.001), and extrathyroidal extension (1% <TT, 4% TT alone, and 9% TT with nodes, P = 0.005). Even after controlling for significant predictors of DSS, extent of the initial operation did not predict survival (HR 0.28 for <TT, 95% CI 0.26-3.11 and HR 0.62 for TT alone, 95% CI 0.17-2.22 compared to TT with nodes, P = NS for all).

Conclusion: According to population-based SEER registry data, the extent of initial resection may not significantly change DSS in patients with MTC confined to the central neck.

Keywords: SEER; disease specific survival; extent of operation; medullary thyroid cancer; thyroidectomy.