Efficacy of external beam radiotherapy and targeted therapy with vandenanib in patients with inoperable and progressive medullary thyroid cancer

The study objective is to evaluate modern-era radiotherapy (external beam radiotherapy, EBRT) and target therapy (TT) outcomes for advanced medullary thyroid cancer (MTC). Materials and methods. Seventy eight consecutive patients with stage IV MTC were evaluated. All of them with relapsing locally advanced or metastatic MTC, 16 had clinically relevant mediastinal involvement, and 59 had distant metastasis; 26 patients received conformal EBRT or intensity-modulated radiotherapy in monomode, 16 patients – conformal EBRT with simultaneous TT with vandenanib, 36 patients – TT in monomode. Median EBRT dose was 60 Gy. Results. Kaplan–Meier estimates of the median overall survival rate was 14 months for radiotherapy in monomode, 48 months – for conformal EBRT + simultaneous TT with vandenanib, 50 months – for TT in monomode. EBRT and TT allows for significantly shorter periods (median 3.8 weeks), to relieve the symptoms of compression-mediated organs and structures of the neck and mediastinum than in the TT (median 10.2 weeks) (p