How is liver cancer staged?
The stage of cancer is a description of how widespread it is. The stage of a liver cancer is one of the most important factors in considering treatment options.
A staging system is a standard way for the cancer care team to sum up information about how far a cancer has spread. Doctors use staging systems to get an idea about a patient's prognosis (outlook) and to help determine the most appropriate treatment.
There are several staging systems for liver cancer, and not all doctors use the same system.
The American Joint Committee on Cancer (AJCC) TNM system
This staging system is based on the results of the physical exam, imaging tests (ultrasound, CT or MRI scan, etc.) and other tests, which are described in the section “How is liver cancer diagnosed?” as well as by the results of surgery if it has been done.
The TNM system for staging contains 3 key pieces of information:
- T describes the number and size of the primary tumor(s), measured in centimeters (cm), and whether the cancer has grown into nearby blood vessels or organs.
- N describes the extent of spread to nearby (regional) lymph nodes.
- M indicates whether the cancer has metastasized (spread) to distant parts of the body. (The most common sites of liver cancer spread are the lungs and bones.)
Numbers or letters that appear after T, N, and M provide more details about each of these factors:
- The numbers 0 through 4 indicate increasing severity.
- The letter X means "cannot be assessed" because the information is not available.
TX: Primary tumor cannot be assessed
T0: No evidence of primary tumor
T1: A single tumor (any size) that hasn't grown into blood vessels
T2: Either a single tumor (any size) that has grown into blood vessels, OR more than one tumor where no tumor is larger than 5 cm (about 2 inches) across
T3a: More than one tumor, with at least one tumor larger than 5 cm across
T3b: At least one tumor (any size) that has grown into a major branch of a large vein of the liver (the portal or hepatic vein)
T4: The tumor (any size) has grown into a nearby organ (other than the gallbladder), OR the tumor is growing into the thin layer of tissue covering the liver (called the visceral peritoneum)
NX: Regional (nearby) lymph nodes cannot be assessed.
N0: The cancer has not spread to the regional lymph nodes.
N1: The cancer has spread to the regional lymph nodes.
M0: The cancer has not spread to distant lymph nodes or other organs.
M1: The cancer has spread to distant lymph nodes or other organs. Liver cancer most often spreads to the lining of the belly (peritoneum), the lungs, and to bones.
Once the T, N, and M groups have been determined, they are then combined to give an overall stage, using Roman numerals I to IV (1 to 4):
Stage I: T1, N0, M0: There is a single tumor (any size) that has not grown into any blood vessels. The cancer has not spread to nearby lymph nodes or distant sites.
Stage II: T2, N0, M0: Either there is a single tumor (any size) that has grown into blood vessels, OR there are several tumors, and all are 5 cm (2 inches) or less across. The cancer has not spread to nearby lymph nodes or distant sites.
Stage IIIA: T3a, N0, M0: There is more than one tumor, and at least one is larger than 5 cm (2 inches) across. The cancer has not spread to nearby lymph nodes or distant sites.
Stage IIIB: T3b, N0, M0: At least one tumor is growing into a branch of a major vein of the liver (portal vein or hepatic vein). The cancer has not spread to nearby lymph nodes or distant sites.
Stage IIIC: T4, N0, M0: A tumor is growing into a nearby organ (other than the gallbladder), OR a tumor has grown into the outer covering of the liver. The cancer has not spread to nearby lymph nodes or distant sites.
Stage IVA: Any T, N1, M0: Tumors in the liver can be any size or number and they may have grown into blood vessels or nearby organs. The cancer has spread to nearby lymph nodes. The cancer has not spread to distant sites.
Stage IVB: Any T, Any N, M1: The cancer has spread to other parts of the body. (Tumors can be any size or number, and nearby lymph nodes may or may not be involved.)
Other liver cancer staging systems
The staging systems for most types of cancer depend only on the extent of the cancer, but liver cancer is complicated by the fact that most patients have damage to the rest of their liver along with the cancer. This also affects treatment options and prognosis.
Although the TNM system defines the extent of liver cancer in some detail, it does not take liver function into account. Several other staging systems have been developed that include both of these factors:
- The Barcelona Clinic Liver Cancer (BCLC) system
- The Cancer of the Liver Italian Program (CLIP) system
- The Okuda system
These staging systems have not been compared against each other. Some are used more than others in different parts of the world, but at this time there is no single staging system that all doctors use. If you have questions about the stage of your cancer or which system your doctor uses, be sure to ask.
Child-Pugh score (cirrhosis staging system)
The Child-Pugh score is a measure of liver function, especially in people with cirrhosis. Many people with liver cancer also have cirrhosis, and in order to treat the cancer, doctors need to know how well the liver is working. This system looks at 5 factors, the first 3 of which are results of blood tests:
- Blood levels of bilirubin (the substance that can cause yellowing of the skin and eyes)
- Blood levels of albumin (a major protein normally made by the liver)
- The prothrombin time (measures how well the liver is making blood clotting factors)
- Whether there is fluid (ascites) in the abdomen
- Whether the liver disease is affecting brain function
Based on these factors, liver function is divided into 3 classes. If all these factors are normal, then liver function is called class A. Mild abnormalities are class B, and severe abnormalities are class C. People with liver cancer and class C cirrhosis are often too sick for surgery or other major cancer treatments.
The Child-Pugh score is actually part of the BCLC and CLIP staging systems mentioned previously.
Localized resectable, localized unresectable, and advanced liver cancer
Formal staging systems such as those described before can often help doctors determine a patient's prognosis (outlook). But for treatment purposes, doctors often classify liver cancers more simply, based on whether or not they can be entirely cut out (resected). Resectable is the medical term meaning "able to be removed by surgery."
Localized resectable cancers
These cancers can be completely removed by surgery. This would include most stage I and some stage II cancers in the TNM system, in patients who do not have cirrhosis. Only a small number of patients with liver cancer have tumors in this group.
Localized unresectable cancers
Cancers that have not spread to the lymph nodes or distant organs but cannot be completely removed by surgery are classified as localized unresectable. This would include some early-stage cancers, as well as stage IIIA, IIIB, and IIIC cancers in the TNM system. There are several reasons that it might not be possible to safely remove a localized liver cancer. If the non-cancerous part of your liver is not healthy (because of cirrhosis, for example), surgery might not leave enough liver tissue for it to function properly. Or curative surgery may not be possible if your cancer is spread throughout the liver or is close to the area where the liver meets the main arteries, veins, and bile ducts.
Cancers that have spread to lymph nodes or other organs are classified as advanced. These would include stage IVA and IVB cancers in the TNM system. Most advanced liver cancers cannot be treated with surgery.
Last Medical Review: 09/25/2013
Last Revised: 09/25/2013