569. INCIDENCE AND ONCOLOGICAL IMPLICATIONS OF THYROID INCIDENTALOMAS IN ESOPHAGEAL CANCER PATIENTS

Abstract

Abstract Although thyroid incidentalomas are regularly encountered during imaging of esophageal cancer, their oncological significance remains unknown. The aim of this study was to describe the incidence and etiology of thyroid incidentalomas observed during the diagnostic workup of esophageal cancer patients. This retrospective cohort study included all esophageal cancer patients referred to or diagnosed in the Amsterdam UMC between January 2012 and December 2016. Radiology and multidisciplinary team meeting reports were reviewed for thyroid incidentalomas. In case of thyroid incidentaloma, the 18FDG-PET/CT or CT was reassessed by a radiologist blinded for the original report. The primary outcome was the incidence and etiology of thyroid incidentalomas. This study included 1,110 esophageal cancer patients, with a median age of 66 years. Most patients were male (77.2%) and had an adenocarcinoma (69.4%). Thyroid incidentalomas were reported in 115 patients (10.4%)/ In 23 (20.0%) patients, additional diagnostics were required to characterize the lesion and two thyroidal lesions proved malignant. One patient was diagnosed with an esophageal cancer metastasis and one patient with a primary thyroid carcinoma. Only the primary thyroid carcinoma resulted in treatment alteration. The other malignant thyroid incidentaloma was in the context of generalized disseminated esophageal disease and no longer eligible for curative treatment. In this study, thyroid incidentalomas were regularly observed, although their oncological significance is limited. Therefore, further etiological examination of thyroidal incidentaloma should only be considered when clinical consequences are to be expected.