Small bowel malignancies: Why are they so rare?

Cancer of the small-bowel is rare and comprises 2.4% of gastrointestinal malignancies. This is despite of its large mucosal surface area and its location between the stomach and the large bowel, two of the most common cancer sites. Nevertheless, there is a similarity between the disease and colorectal cancer. Therefore, it is of great interest to study the protective mechanisms of this organ and how tumor arises when these protectors fail. Among the risk factors for small bowel malignancies are Inflammatory Bowel Disease (IBD), familial syndromes, and lifestyle parameters (alcohol consumption, smoking, and high fat and animal protein diet). Due to the unusual symptoms, the rarity of the disease, and the difficulty in small bowel imaging, a correct diagnosis is often delayed. The treatment of choice, which allows full recovery, as in other malignancies of the gastrointestinal tract, is surgical resection of the tumor.