Carcinoid tumors are slow-growing cancers affecting the cells that produce hormones. They usually start in the lungs or digestive system, but may also be found in the testicles, ovaries or pancreas. 

People at a higher risk of developing carcinoid tumors include those with certain genetic diseases, women, African-Americans, and people over 40 years of age. Symptoms of carcinoid tumors vary but are usually related to changes in the cells that make hormones. They may include stomach pain, diarrhea, constipation, feelings of nausea, trouble breathing, blood in the stool, and weight loss. 

Treatment of carcinoid tumors may involve surgery to remove the growth, but medication may also be prescribed to slow further growth. Drug classes commonly prescribed as part of treatment for carcinoid tumors include antigrowth hormones and antineoplastic monoclonal antibodies.