Incidence and Mortality
Estimated new cases and deaths from thyroid cancer in the United States in 2014:
New cases: 62,980.
Carcinoma of the thyroid gland is an uncommon cancer but is the most common malignancy of the endocrine system. Differentiated tumors (papillary or follicular) are highly treatable and usually curable. Poorly differentiated tumors (medullary or anaplastic) are much less common, are aggressive, metastasize early, and have a much poorer prognosis...
Management of adenocarcinoma histology, which accounts for 90% to 95% of all gastric malignancies, is discussed in this summary. There are changing epidemiologic patterns in the United States regarding the anatomic location of esophagogastric cancers, with a trend of decreased occurrence of distal or noncardia gastric cancers. However, in persons aged 25 to 39 years, there has been a significant increase in the incidence of noncardia gastric cancers from 0.27 cases per 100,000 individuals (1977-1981) to 0.45 cases per 100,000 individuals (2002-2006). Additional studies are needed to confirm the observed increases in noncardia gastric cancers in this specific age group.
In contrast to the overall stable trend for noncardia gastric cancers, earlier studies demonstrated an increased incidence of adenocarcinomas of the gastric cardia of 4% to 10% per year from the mid-1970s to the late 1980s. Similarly, the incidence of gastroesophageal junction adenocarcinomas increased sharply, from 1.22 cases per 100,000 individuals (1973-1978) to 2.00 cases per 100,000 individuals (1985-1990). Since that time, incidence has remained steady, with an incidence of 1.94 cases per 100,000 individuals (2003-2008). More recent data demonstrate that the incidence of gastric cardia cancers has been relatively stable, although an increase has been observed, from 2.4 cases per 100,000 individuals (1977-1981) to 2.9 cases per 100,000 individuals (2001-2006) in the Caucasian population. The reasons for these temporal changes in incidence are unclear.
In the United States, gastric cancer ranks 14th in incidence among the major types of cancer malignancies. While the precise etiology is unknown, acknowledged risk factors for gastric cancer include the following:[5,6,7]