Staging is the process of finding out how widespread a cancer is. The stage of a liver cancer is the most important factor in considering treatment options. The tests described above (in the section "How Is Liver Cancer Diagnosed?") are the ones used to determine the stage of the cancer.

A staging system is a standardized way for the cancer care team to summarize information about how far a cancer has spread. A major system used to describe the stages of liver cancer is the American Joint Committee on Cancer (AJCC) TNM system. But there are several other systems, and none is universally accepted.

The American Joint Committee on Cancer (AJCC) TNM System

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 spread to the organs next to the tumor.
• N describes the extent of spread to nearby (regional) lymph nodes.
• M indicates whether the cancer was metastasized (spread) to other organs of the body (The most common sites of liver cancer spread are the lungs and bones.).

Numbers or letters appear after T, N, and M to 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.

T Groups

• TX: Primary tumor cannot be assessed.
• T0: No evidence of primary tumor.
• T1: Single tumor (any size) without invasion into blood vessels.
• T2: Single tumor (any size) with invasion into blood vessels, OR multiple tumors where none are greater than 5 cm (about 2 inches) across.
• T3: Multiple tumors that are greater than 5 cm (about 2 inches) across, OR a tumor involving a major branch of the portal or hepatic vein(s)
• T4: Tumor invading a nearby organ (other than the gallbladder), OR tumor invading the visceral peritoneum (covering surrounding the liver).

N Groups

• NX: Regional 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.

M Groups

• MX:Distant spread cannot be assessed.
• 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.

The T, N, and M groups are then combined to give an overall stage:

Stage I: T1, N0, M0: There is a single tumor (any size) that does not invade blood vessels.

Stage II:T2, N0, M0: There is a single tumor (any size) that does invade blood vessels; OR there are several tumors, and all are less than 5 cm (2 inches) in diameter.

Stage IIIA: T3, N0, M0: There are several tumors, and at least one is larger than 5 cm (2 inches) in diameter; OR a tumor invades a branch of the major liver blood vessels (portal vein or hepatic vein).

Stage IIIB: T4, N0, M0: A tumor invades a nearby organ (other than the gallbladder); OR tumor has penetrated the outer covering of the liver.

Stage IIIC:Any T, N1, M0: The cancer has invaded nearby lymph nodes. (Tumors can be any size or number.)

Stage IV: 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.)

Localized Resectable, Localized Unresectable, and Advanced Liver Cancer

For treatment purposes, doctors often classify liver cancers by whether or not they can be entirely cut out (resected). Resectable is the medical term meaning "able to be removed by surgery."

Less than 30% of patients with liver cancer have resectable tumors that can be completely removed by surgery. This would include most stage I and some stage II cancers in the TNM system.

Cancers that have not spread beyond the liver but cannot be completely removed by surgery are classified as localized unresectable. This would include some early stage cancers, as well as stage IIIA and IIIB 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 (due to cirrhosis, for example), surgery might not leave enough liver tissue behind for it to function properly. Also, curative surgery may not be possible if your cancer has 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 throughout most of the liver and/or have spread to lymph nodes or other organs are classified as advanced. These would include stage IIIC and stage IV cancers in the TNM system. Most advanced liver cancers cannot be treated with surgery.

Survival Rates Based on Extent of Liver Cancer

Since symptoms of liver cancer often do not appear until the disease is advanced, only a small number of liver cancers are found in the early stages and can be removed with surgery. The 5-year survival rate for patients with resectable early stage cancer is in the range of 30% to 60%. This percentage drops for more advanced cancers or with more severe liver disease. The 5-year survival rate for people with advanced liver cancer (cancer that has spread widely throughout the liver or to distant sites) is less than 5%, and the average survival time is often measured in months.

The overall 5-year survival rate from liver cancer is less than 10%. One reason for this low survival rate is that most patients with liver cancer also have other liver problems such as cirrhosis, which itself can be fatal.

The 5-year survival rate refers to the percentage of patients who live at least 5 years after their cancer is diagnosed. Five-year rates are used to produce a standard way of discussing prognosis. Of course, some people live much longer than 5 years.

Child-Pugh Score (Cirrhosis Staging System)

Because people with liver cancer often have 2 diseases, their cancer and cirrhosis, doctors treating liver cancer need to know the extent of the cirrhosis. They use a system called the Child-Pugh score. This system depends on 5 factors, the first 3 of which are 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 in the abdomen
• whether the liver disease is affecting brain function

Based on the score, 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 generally too sick for any treatment.