Dr Aditya Reelkar is the Best Gastrointestinal Cancer Surgeon in Dadar, Mahim West, Mahim and Mumbai. Gastrointestinal (GI) cancer refers to malignant tumors in the digestive system, including the esophagus, stomach, liver, pancreas, and intestines. Initial symptoms can include unexplained weight loss, persistent indigestion, or heartburn. Other symptoms, such as difficulty swallowing, persistent abdominal pain, blood in the stool, or jaundice, can indicate more advanced disease. Risk factors include lifestyle choices like smoking and poor diet, obesity, heavy alcohol use, and a family history of GI cancer. What is gastrointestinal surgery? Gastrointestinal surgery is a treatment for diseases of the parts of the body involved in digestion. This includes the esophagus (ee-sof-uh-gus), stomach, small intestine, large intestine, and rectum. It also includes the liver, gallbladder, and pancreas.