Signs, Symptoms, and Diagnostics

Signs and Symptoms: Generally, the most common symptoms of adenocarcinoma of the pancreas include loss of appetite, weight loss, abdominal discomfort and nausea. As these are all fairly non-specific symptoms, there is often delay in getting to the final diagnosis. The most common physical sign of pancreatic cancer is jaundice, with or without associated itching. Preceding a medical evaluation often requires a high index of suspicion by the patient or by medical personnel.

The main reason for the poor prognosis (outlook for survival) of cancer of the pancreas is that very few of these cancers are found early. Because the pancreas is located deep inside the body, early tumors cannot be seen or felt by health care providers during routine physical examinations. There are currently no blood tests or other screening tests that can accurately detect cancers of the pancreas.

A substance called CA 19-9 is present in the cells of the pancreas. It is also released into the blood by these cells and can be detected by blood tests. However, by the time blood levels are high enough to be consistently detected by available methods, the cancer is no longer in its early stages. This test is sometime used after treatment of the pancreas to determine if the tumor has recurred.

Current diagnosis methods: Generally, in the U.S., the dynamic spiral (or helical) CT scan with IV and oral contrast media enhancement is considered to be the procedure of choice for the staging of pancreatic cancer. With the latest equipment and with experienced operators and evaluators, this approach can detect up to 90-95% of pancreatic ductal adenocarcinomas. Tumors greater than ½ to one-inch can usually be detected. These CT’s can predict unresectability about 90% of the time, but are less accurate at predicting surgical resectability. Its strength in this regard is related to its ability to demonstrate pancreatic extension involving local arteries. This technique is less reliably able to show subtle local vein involvement, to detect small liver metastasis in a CT. The exam is not generally indicated for pregnant women.

Transabdominal ultrasound is a more popular procedure outside of the U.S. where operators are more experienced and generally the patient population may be less obese—a big problem in imaging structures through the abdomen. Patients suffering from obesity are more difficult to image because tissue attenuates the sound waves as they pass deeper into the body. In experienced hands, with a relatively “thin” patient and with good equipment, this ultrasound approach can often pick up smaller tumors than are even found by the CT procedure. However, a limitation is that ultrasound waves do not pass through air, therefore an evaluation of the stomach, small intestine and large intestine may be limited. Intestinal gas may also prevent visualization of deeper structures, such as the pancreas and aorta.

New diagnostic methods—recent research suggests that two imaging tests, endoscopic ultrasound retrograde cholangiopancreatography (ERCP), used together, can help find pre-cancerous changes called dysplasia among members of high-risk families. EUS uses sound waves to produce images of the pancreatic ducts. For ERCP, a contrast dye is injected into the pancreatic ducts before x-rays are taken. Both tests also use endoscopy (a lighted tube is passed down the throat to reach the part of the intestine next to the pancreas).

Researchers are also looking at tests for detecting acquired (i.e., not inherited) genetic changes in pancreatic cancer and pancreatic ductal dysplasia (pre-cancerous changes in pancreatic duct cells). One of the most common DNA changes in these conditions affects the K-ras oncogene and alters regulation of cell growth. New diagnostic tests are often able to recognize this change in samples of pancreatic juice collected at the time of ERCP.

The endoscopic ultrasound (ultrasound through a tube which is placed down the esophagus) is very good at finding small tumors in the pancreas. And laparoscopic ultrasound (ultrasound through a small tube placed through the abdomen into the region of the pancreas) is particularly sensitive at finding liver and peritoneal involvement, without having to resort to full surgery.

Pre-operative angiography (viewing contrast dye placed in select arteries) is recommended by some surgeons, although the introduction of spiral CT has provided a competing option—with some controversy about which approach may be best as a matter of course and in selected situations.

CT or ultrasound-guided percutaneous biopsy (via needle) can retrieve a bit of pancreatic tumor tissue for histologic viewing without requiring full surgery. There exists some concern about the risk of inadvertent “seeding” of the tumor into the peritoneum with this technique, but some experts feel that the potential benefit outweighs the potential harm in selected cases.

For now, EUS, ERCP, and tests for K-ras changes are options for people with a strong family history of of pancreatic cancer but not recommended for widespread testing of people at average risk who do not have any symptoms.

New technologies—In May 2002, Fujirebio Diagnostics received FDA marketing clearance for its CA 19-9 Radioimmunoassay for monitoring of pancreatic cancer patients. The CA 19-9 RIA is a simple laboratory test that enables physicians to evaluate and monitor the effectiveness of treatment and is the first blood test cleared for use in pancreatic cancer. It is the only immunoassay for CA 19-9 approved for market in the United States. Recent reports, mainly from Europe, have shown that serial measurements of serum CA 19-9 can reflect the response of patients to chemotherapy. The availability of the CA 19-9 test in the U.S. gives a new tool for early assessment of the effectiveness of the many new drugs that are becoming available for the treatment of metastatic cancer of the pancreas. CA 19-9 is already available in many countries throughout the world, and is used by oncologists in these countries to measure the effectiveness of pancreatic cancer treatment.

As we see, a number of techniques are currently used to diagnose pancreatic cancer, without one being decisively efficient in all cases of pancreatic cancer. In parallel, new treatment methods are developed both by private companies and university research centers.