Thyroid Cancer: 20-Year Comparative Mortality and Survival Analysis of Six Thyroid Cancer Histologic Subtypes by Age, Sex, Race, Stage, Cohort Entry Time-Period and Disease Duration (SEER*Stat 8.3.2) A Systematic Review of 145,457 Cases for Diagnosis Years 1993-2013.

Background: -Incidence and prognosis of cancers of the endocrine glands vary greatly by stage and histologic type, and, thyroid cancer accounts for most (92%) of the cancers of the endocrine glands. It is the 8^th most common of cancers and has been rising in incidence since 1975. It remains a formidable health threat in the United States in 2016 with estimated cases of 64,300 and 1980 deaths.

Objective: -Provide 20-year comparative mortality analysis of thyroid cancer in a recent group of 145,457 staged cases (97.5%) of a total of 149,202 patients during the 1993-2013 entry time-period in six histologic subtypes by age, sex, race, stage and disease duration.

Methods: -Population-based data from SEER registries, ¹ 1973-2013, (SEER*Stat 8.3.2.) were analyzed.

Results: - Tables 1 - 8 provide basic SEER epidemiologic, demographic, case-statistics, and comparative mortality follow-up data of 4 principal and 2 supplementary thyroid cancer oncotypes by age, sex, race, stage and disease duration of patients in the 1993-2013 time-period. [Table: see text] [Table: see text] [Table: see text] [Table: see text] [Table: see text] [Table: see text] [Table: see text] [Table: see text] Conclusions.-Thyroid cancer when localized has a very good prognosis, with no significant excess mortality after diagnosis in papillary and papillary follicular variant cancers (PFV). Because nearly two thirds of thyroid cancers are localized, and excess death rate (EDR) is small in patients with regional cancer under age 50, overall excess mortality for all ages also virtually disappeared after 10 years in papillary and follicular cancer. Overall, the 5-year survival rate is greater than 90% for papillary and follicular carcinomas. Nevertheless, because of the marked predominance of papillary carcinoma, the continued increase in its relative frequency and annual projected deaths, thyroid carcinoma remains a significant health concern in the current era.