Understanding Primary Liver Cancer: Breaking down the Liver Cancer Stages

When diagnosed with primary liver cancer, most patients are naturally anxious to learn about the severity of their disease—in other words, the stage of liver cancer they have. The cancer stage provides an indication of the disease's outcome and the types of treatment that may be necessary. Being well-informed about liver cancer stages can help patients prepare for what is to come physically, mentally and emotionally. It is also important to know about the severity of background liver disease, which is often present in conjunction with the cancer.

The most common staging system for primary liver cancer in the United States follows the American Joint Committee on Cancer (AJCC) staging manual. The 8^th and latest edition of the staging manual details both clinical and pathological staging systems for liver cancer.

The clinical stage is the stage given regardless of the type of treatment. It is based on physical examinations, imaging tests, diagnostic tests and biopsies.

The pathological stage is the stage given after surgical resection of the tumor or liver transplantation, if these treatments are carried out. It is based on information obtained from the surgery, together with any tests done before surgery. The pathological stage tends to be more reflective of the patient’s outlook than the clinical prognosis stage, as it is based on more accurate information on the size and spread of cancer.

Both the clinical stage and pathological stage are based on:

• Size of primary tumor
• Nodal involvement
• Presence of distant metastases

The size of the primary tumor, nodal involvement and presence of distant metastases are described using the AJCC TNM system.

Primary tumor (T)

This category is based on the size of the tumor, the number of tumors and whether or not the cancer has spread to nearby structures such as the veins in the liver. It is described with the letter ‘T’ followed by ‘X’, 0, 1a, 1b, 2, 3 or 4.

TX: Size of the tumor cannot be measured.

T0: No tumor is present.

T1a: A single tumor 2 cm (⅘ of an inch) or smaller, with or without vascular invasion.

T1b: A single tumor larger than 2 cm (⅘ of an inch), without vascular invasion.

T2: Either a single tumor larger than 2 cm (⅘ of an inch) with vascular invasion OR multiple tumors with none over 5 cm (about 2 inches).

T3: Multiple tumors with at least one being more than 5 cm (about 2 inches).

T4: Any size of tumor or multiple tumors growing into a major branch of a large vein of the liver (portal or hepatic) OR Any size of tumor or multiple tumors directly invading adjacent organs (other than the gallbladder)

Nodal involvement (N)

This category looks at how many lymph nodes the cancer has spread to, if any. It is described with the letter ‘N’ followed by ‘X’, 0 or 1. This is a brief and simplified description of nodal involvement:

NX: The lymph nodes cannot be assessed.

N0: No cancer has advanced to the neighboring lymph nodes.

N1: Cancer has spread to the neighboring lymph nodes.

Distant metastases (M)

This category determines if the cancer has spread to more distant parts of the body, such as the lungs or bones, after imaging tests, physical examination or biopsy. It is described with the letter ‘M’ followed by 0 or 1.

M0: Cancer has not advanced to other parts of the body.

M1: Cancer has advanced to distant organs.

Depending on the TNM assessment, the cancer is clinically staged according to the categories below.

While the TNM system is widely used, it does not account for damage to the liver other than the presence of the tumor(s). As such, other staging systems, such as the Barcelona Clinic Liver Cancer (BCLC) system, have been developed to account for other factors, such as liver function, to give more information about treatment options and survival outlook. In such staging systems, the Child-Pugh score is used to measure liver function, especially in people with cirrhosis. It looks at factors such as blood bilirubin, blood albumin levels, presence of fluid in the abdomen, how fast your blood clots and whether the liver disease is affecting brain function.

Different staging systems have different names for the stages. The BCLC staging system, for example, has five stages:

• Stage 0: Very early
• Stage A: Early
• Stage B: Intermediate
• Stage C: Advanced
• Stage D: End-stage

Different countries will use different systems to stage liver cancer, so if you are unsure, it is best to clarify this with your doctor.

Learning your liver cancer stage can be a challenging and emotional experience, but it is an essential part of your cancer journey. Understanding the stages of liver cancer can give you a greater sense of control and help you feel more prepared for what lies ahead. It's natural to feel a range of emotions after receiving a diagnosis, and having a strong support system to lean on throughout the process can provide some comfort. Rest assured that your healthcare team will be with you every step of the way, answering your questions and providing guidance as you navigate your treatment.