Pancreatic Cancer

Symptoms of pancreatic cancer such as pain and weight loss are nonspecific, leading to a later diagnosis by which time the disease has spread. By the time of diagnosis, 90% of patients have locally advanced tumors that have involved retroperitoneal structures, spread to regional lymph nodes, or metastasized to the liver or lung.

Most patients have severe upper abdominal pain, which usually radiates to the back. Weight loss is common. Adenocarcinomas of the head of the pancreas cause obstructive jaundice (which can cause pruritus) in 80 to 90% of patients. Cancer in the body and tail may cause splenic vein obstruction, resulting in splenomegaly, gastric and esophageal varices, and gastrointestinal hemorrhage.

The cancer causes diabetes in 25 to 50% of patients, leading to symptoms of glucose intolerance (eg, polyuria and polydipsia). Pancreatic cancer can also interfere with production of digestive enzymes by the pancreas (pancreatic exocrine insufficiency) in some patients and with the ability to break down food and absorb nutrients (malabsorption Overview of Malabsorption Malabsorption is inadequate assimilation of dietary substances due to defects in digestion, absorption, or transport. Malabsorption can affect macronutrients (eg, proteins, carbohydrates, fats)... read more ). This malabsorption causes bloating and gas and a watery, greasy, and/or foul-smelling diarrhea, leading to weight loss and vitamin deficiencies.

The preferred tests are an abdominal helical CT using pancreatic technique or MRI/MRCP; these are followed by endoscopic ultrasonography with fine-needle aspiration (EUS/FNA) for tissue diagnosis and to assess surgical resectability. CT or MRI/MRCP is typically chosen based on local availability and expertise. Even if these imaging tests show apparent unresectable or metastatic disease, EUS/FNA or a percutaneous needle aspiration of an accessible lesion is done to obtain a tissue diagnosis. If CT shows a potentially resectable tumor or no tumor, MRI/MRCP or endoscopic ultrasonography may be used to stage disease or detect small tumors not visible with CT. Patients with obstructive jaundice may have endoscopic retrograde cholangiopancreatography (ERCP) as the first diagnostic procedure.

Routine laboratory tests should be done. Elevation of alkaline phosphatase and bilirubin indicate bile duct obstruction or liver metastases. Pancreas-associated antigen CA 19-9 may be used to monitor patients diagnosed with pancreatic carcinoma and to screen those at high risk (eg, those with hereditary pancreatitis; ≥ 2 first-degree family members with pancreatic cancer, Peutz-Jeghers syndrome Peutz-Jeghers Syndrome Peutz-Jeghers syndrome is an autosomal dominant disease with multiple hamartomatous polyps in the stomach, small bowel, and colon along with distinctive pigmented skin lesions. Most (66 to 94%)... read more , or BRCA2 or HNPCC Lynch Syndrome Lynch syndrome is an autosomal dominant disorder responsible for 2 to 3% of cases of colorectal cancer. Symptoms, initial diagnosis, and treatment are similar to other forms of colorectal cancer... read more mutations). However, this test is not sensitive or specific enough to be used for population screening. Elevated levels should drop with successful treatment; subsequent increases indicate progression. Amylase and lipase levels are usually normal.

Prognosis for pancreatic cancer varies with stage but overall is poor (5-year survival: < 2%), because many patients have advanced disease at the time of diagnosis.

About 80 to 90% of cancers are considered surgically unresectable at time of diagnosis because of metastases or invasion of major blood vessels. Depending on location of the tumor, the procedure of choice for resection of the cancer is most commonly a Whipple procedure (pancreaticoduodenectomy). Adjuvant therapy with gemcitabine-based combinations is now recommended (1 Treatment reference Pancreatic cancer, primarily ductal adenocarcinoma, accounts for an estimated 57,600 cases and 47,050 deaths in the US annually ( 1). Symptoms include weight loss, abdominal pain, and jaundice... read more ) and external beam radiation therapy is typically given, resulting in about 40% 2-year and 25% 5-year survival. This combination is also used for patients with localized but unresectable tumors and results in median survival of about 1 year. Gemcitabine and other drugs may be more effective than 5-fluorouracil–based chemotherapy, but no drug, singly or in combination, is clearly superior in prolonging survival. Patients with hepatic or distant metastases may be offered chemotherapy as part of an investigational program, but the outlook is dismal with or without such treatment and some patients may choose to forego it.

If an unresectable tumor is found at operation and gastroduodenal or bile duct obstruction is present or pending, a double gastric and biliary bypass operation is usually done to relieve obstruction. In patients with inoperable lesions and jaundice, endoscopic placement of a bile duct stent relieves jaundice. Duodenal stenting is frequently done. However, surgical bypass should be considered in patients with unresectable lesions if life expectancy is > 6 to 7 months because of complications associated with stents.