Because the pancreas lies deep in the belly in front of the spine, pancreatic cancer often grows silently for months before it is discovered. Early symptoms can be absent or quite subtle. More easily identifiable symptoms develop once the tumor grows large enough to press on other nearby structures, such as nerves (which causes pain), the intestines (which affects appetite and causes nausea along with weight loss), or the bile ducts (which causes jaundice or a yellowing of the skin and can cause loss of appetite and itching). Symptoms in women rarely differ from those in men.
Once the tumor sheds cancer cells into the blood and lymph systems and metastasizes, additional symptoms usually arise, depending on the location of the metastasis. Frequent sites of metastasis for pancreatic cancer include the liver, the lymph nodes, and the lining of the abdomen (called the peritoneum). Unfortunately, most pancreatic cancers are found after the cancer has grown beyond the pancreas or has metastasized to other places.
In general, the signs and symptoms of pancreatic cancer can be produced by exocrine or endocrine cancer cells. Exocrine pancreatic cancer signs and symptoms can include
- dark urine,
- itchy skin,
- light-colored stools,
- pain in the abdomen or the back,
- poor appetite and weight loss,
- digestive problems (pale and/or greasy stools, nausea, and vomiting),
- blood clots,
- enlarged gallbladder.
- The signs and symptoms of endocrine pancreatic cancers are often related to the excess hormones that they produce and consequently to a variety of different symptoms. Such symptoms are related to the hormones and are as follows:
- Insulinomas: Insulin-producing tumors that lower blood glucose levels can cause low blood sugars, weakness, confusion, coma, and even death.
- Glucagonomas: Glucagon-producing tumors can increase glucose levels and cause symptoms of diabetes (thirst, increased urination, diarrhea and skin changes, especially a characteristic rash termed necrolytic migratory erythema).
- Gastrinomas: Gastrin-producing tumors trigger the stomach to produce too much acid, which leads to ulcers, black tarry stools, and anemia.
- Somatostatinomas: Somatostatin-producing tumors result in other hormones being overregulated and producing symptoms of diabetes, diarrhea, belly pain, jaundice, and possibly other problems.
- VIPomas: These tumors produce a substance called vasoactive intestinal peptide (VIP) that may cause severe watery diarrhea and digestive problems along with high blood glucose levels.
- PPomas: These tumors produce pancreatic polypeptide (PP) that affects both endocrine and exocrine functions, resulting in abdominal pain, enlarged livers, and watery diarrhea.
- Carcinoid tumors: These tumors make serotonin or its precursor, 5-HTP, and may cause the carcinoid syndrome with symptoms of flushing of the skin, diarrhea, wheezing, and a rapid heart rate that occurs episodically; eventually, a heart murmur, shortness of breath, and weakness develop due to damage to the heart valves.
- Nonfunctioning neuroendocrine tumors don’t make excess hormones but can grow large and spread out of the pancreas. Symptoms then can be like any of the endocrine pancreatic cancers described above.