Impact of Thyroglobulin on Survival and Prognosis of Differentiated Thyroid Cancer

Abstract

Proper assessment of risk factors contributes to the principle management of differentiated thyroid carcinoma post operatively. Aim of the study: to investigate the effect of Thyroglobulin (Tg) levels on prognosis together with other risk factors for Differentiated Thyroid Cancer (DTC). Patients and methods: Medical records of all patients with DTC presented to Clinical Oncology and Nuclear Medicine Department referred from Diabetes & Endocrine unit (Internal Medicine Hospital) and Surgery Department Mansoura University from 2011-2016 were retrospectively reviewed. Patients with distant metastasis or who lost follow-up were excluded. So data of 220 patients were analyzed. Data collected included pre-surgical assessment, also surgical interference either total or near total thyroidectomy with or without lymph node neck dissection were reviewed. Different prognostic factors that affect progression free survival (PFS) include age, umorsize, ymph node status, ex, m ultifocality, capsular infiltration, vascular invasion and Tg level were evaluated through multivariate analysis. Results: Most of the patients included were <45 years (69.1%). Incidence of the disease was higher in female ( 80%) with papillary type predominance (80.9%). About 59.5% of cases presented with tumor size ≤ 2 cm and multifocality was reported in 13.6%. While 30% had lymph node metastasis, 11% had vascular invasion. Capsular infiltration was observed in 15% and most of them showed Tg level ≤ 10 ng/ml (68.2%). About 70% received ablative radioiodine. The 5-year Progression Free Survival (PFS) was 85%. On multivariate analysis of variable prognostic factors on PFS , we found that tumor size, age, lymph node status, capsular infiltration, Tg level and vascular invasion significantly affect ed PFS (P = 0.01, 0.005, 0.004, 0.005, 0.02, 0.003) respectively. While sex, pathological type and multifocality were not (P = 0.9, 0.4, 0.6) respectively. Conclusion: Postoperative Tg level is a statistically significant prognostic factor together with other risk factors .