Pancreatic cancer symptoms usually do not appear in the early stages. If they do they may be mistaken for signs of another condition. Additionally, the pancreas is deep inside the body, behind several other organs. This makes it difficult to feel or see without proper equipment. These factors mean pancreatic cancer is hard to diagnose.
Several diagnostic tests are usually required to find and stage (determine extent of) pancreatic cancer. Accurate diagnosis and staging are important because they help your doctors choose the best type of treatment.
Diagnostic tests for pancreatic cancer
One or more of the following tests may be used to test for pancreatic cancer. These tests also may be used to find out if the cancer has spread and if treatment is working.
One way to diagnose pancreatic cancer is by imaging the pancreas and surrounding areas. These tests can be used to uncover potential tumors, see if a tumor has spread and determine whether treatment is working. During some types of imaging tests, tissue samples for biopsy can be obtained if cancer is detected. Common imaging tests for pancreatic cancer include:
- CT scan: A painless, outpatient procedure that uses a series of X-rays taken from different angles to provide an image of the pancreas. Unless other factors make its use unsuitable, a CT scan optimized for imaging the pancreas is the primary option for diagnosis and staging of pancreatic cancer.
- MRI scan: A painless, outpatient procedure that uses magnets, rather than x-rays, to provide an image of the pancreas. While CT scans are more commonly used, an MRI can sometimes help visualize tumors that are hard to see.
- Endoscopic ultrasound: A special endoscope with an ultrasound probe is inserted into the mouth and directed to the first part of the small intestine to show the pancreas on a video screen. If cancer is suspected, a small piece of tissue can be taken for biopsy.
- Endoscopic retrograde cholangiopancreatography (ERCP): A special endoscope is inserted through the mouth and directed to the first part of the small intestine. A smaller tube is then inserted through the endoscope into the bile ducts. A dye is injected through the tube, and an X-ray is taken. If cancer is suspected, a small piece of tissue can be taken for biopsy. If the ducts are blocked by a tumor, a stent may be inserted to relieve blockage. This may help alleviate stomach pain and digestive problems.
This is the removal of a small piece of tissue to view under a microscope to determine if there’s cancer. While imaging tests can indicate the presence of pancreatic cancer, a biopsy is almost always needed to confirm a diagnosis.
In most cases, biopsies are obtained during either an endoscopic ultrasound or endoscopic retrograde cholangiopancreatography (ERCP) for localized pancreas cancer.
For patients with metastatic disease, a biopsy of the most accessible site is often preferred, such as a liver biopsy through CT-guided fine-needle aspiration.
Blood samples can be taken and examined for levels of substances that indicate the function of the liver, such as bilirubin, or other organs that may be affected by a pancreatic tumor. Blood samples may also be used to check the levels of tumor markers, such as CA-19-9. High levels of these markers may indicate the presence of pancreatic cancer. Levels can be used to monitor treatment.
Pancreatic Cancer Staging
If you are diagnosed with pancreatic cancer, your doctor will determine the stage of the disease. Staging is a way of classifying cancer by how much disease is in the body and where it has spread. This helps the doctor plan the best way to treat the cancer. Once the staging classification is determined, it stays the same even if treatment is successful or the cancer spreads.
Pancreatic cancer stages
(Source: 8th Edition of the American Joint Committee on Cancer (AJCC) Staging Manual)
Stage 0: Abnormal pancreatic cells are found only in the lining of the pancreas. These cells have the potential to become cancer. Stage 0 also is called carcinoma in situ.
Stage I: Cancer has formed and is in the pancreas only. This stage is divided into IA and IB, based on tumor size.
- Stage IA: The tumor is 2 centimeters or smaller
- Stage IB: The tumor is larger than 2 centimeters
Stage II: Cancer is large or has spread to lymph nodes. This stage is divided into IIA and IIB.
- IIA: The tumor is larger than 4 centimeters
- IIB: Cancer has spread to the nearby lymph nodes
Stage III: Cancer has spread to nearby major blood vessels or to four or more lymph nodes near the pancreas.
Stage IV: Cancer has spread to distant organs beyond the pancreas, such as the liver, lung and peritoneal cavity.
While the staging guidelines above are an important part of every pancreatic cancer diagnosis and treatment plan, MD Anderson doctors more commonly rely on a “functional” staging system that is based on the likelihood that the cancer can be removed by surgery.