Review Epidemiology of Cancers of the Small Intestine: Trends, Risk Factors, and Prevention Adam Barsouk 1, Prashanth Rawla 2,*, Alexander Barsouk 3 and Krishna Chaitanya Thandra 4 1 Hillman Cancer Center, University of Pittsburgh, Pittsburgh, PA 15232, USA;
[email protected] 2 Department of Medicine, Sovah Health, Martinsville, VA 24112, USA 3 Hematologist-Oncologist, Allegheny Health Network, Pittsburgh, PA 15212, USA;
[email protected] 4 Department of Pulmonary and Critical Care Medicine, Sentara Virginia Beach General Hospital, Virginia Beach, VA 23454, USA;
[email protected] * Correspondence:
[email protected]; Tel.: +1-732-982-7357 Received: 22 February 2019; Accepted: 14 March 2019; Published: 17 March 2019 Abstract: The latest data from the United States and Europe reveal that rare small intestine cancer is on the rise, with the number of cases having more than doubled over the past 40 years in the developed world. Mortality has grown at a slower pace, thanks to improvements in early diagnosis and treatment, as well as a shift in the etiology of neoplasms affecting the small intestine. Nevertheless, 5-year survival for small intestine adenocarcinomas has lingered at only 35%. Lifestyle in developed nations, including the rise in obesity and physical inactivity, consumption of alcohol, tobacco, and red and processed meats, and occupational exposures may be to blame for the proliferation of this rare cancer. Identification of hereditary and predisposing conditions, likely to blame for some 20% of cases, may help prevent and treat cancers of the small intestine. Studies of the neoplasm have been limited by small sample sizes due to the rarity of the disease, leaving many questions about prevention and treatment yet to be answered.