This is a medical question of type : stages 
 What are the stages of Childhood Liver Cancer ? 
 Key Points
                    - After childhood liver cancer has been diagnosed, tests are done to find out if cancer cells have spread within the liver or to other parts of the body.     - There are two grouping systems for childhood liver cancer.    - There are four PRETEXT and POSTTEXT groups:         - PRETEXT and POSTTEXT Group I     - PRETEXT and POSTTEXT Group II     - PRETEXT and POSTTEXT Group III     - PRETEXT and POSTTEXT Group IV        - There are three ways that cancer spreads in the body.    - Cancer may spread from where it began to other parts of the body.
                
                
                    After childhood liver cancer has been diagnosed, tests are done to find out if cancer cells have spread within the liver or to other parts of the body.
                    The process used to find out if cancer has spread within the liver, to nearby tissues or organs, or to other parts of the body is called staging. In childhood liver cancer, the PRETEXT and POSTTEXT groups are used instead of stage to plan treatment. The results of the tests and procedures done to detect, diagnose, and find out whether the cancer has spread are used to determine the PRETEXT and POSTTEXT groups.
                
                
                    There are two grouping systems for childhood liver cancer.
                    Two grouping systems are used for childhood liver cancer:         - The PRETEXT group describes the tumor before the patient has treatment.    - The POSTTEXT group describes the tumor after the patient has treatment.
                
                
                    There are four PRETEXT and POSTTEXT groups:
                    The liver is divided into 4 sections. The PRETEXT and POSTTEXT groups depend on which sections of the liver have cancer.     PRETEXT and POSTTEXT Group I     In group I, the cancer is found in one section of the liver. Three sections of the liver that are next to each other do not have cancer in them.       PRETEXT and POSTTEXT Group II     In group II, cancer is found in one or two sections of the liver. Two sections of the liver that are next to each other do not have cancer in them.       PRETEXT and POSTTEXT Group III     In group III, one of the following is true:            -  Cancer is found in three sections of the liver and one section does not have cancer.     - Cancer is found in two sections of the liver and two sections that are not next to each other do not have cancer in them.              PRETEXT and POSTTEXT Group IV     In group IV, cancer is found in all four sections of the liver.
                
                
                    There are three ways that cancer spreads in the body.
                    Cancer can spread through tissue, the lymph system, and the blood:         - Tissue. The cancer spreads from where it began by growing into nearby areas.     - Lymph system. The cancer spreads from where it began by getting into the lymph system. The cancer travels through the lymph vessels to other parts of the body.     - Blood. The cancer spreads from where it began by getting into the blood. The cancer travels through the blood vessels to other parts of the body.
                
                
                    Cancer may spread from where it began to other parts of the body.
                    When cancer spreads to another part of the body, it is called metastasis. Cancer cells break away from where they began (the primary tumor) and travel through the lymph system or blood.         - Lymph system. The cancer gets into the lymph system, travels through the lymph vessels, and forms a tumor (metastatic tumor) in another part of the body.    - Blood. The cancer gets into the blood, travels through the blood vessels, and forms a tumor (metastatic tumor) in another part of the body.        The metastatic tumor is the same type of cancer as the primary tumor. For example, if childhood liver cancer spreads to the lung, the cancer cells in the lung are actually liver cancer cells. The disease is metastatic liver cancer, not lung cancer.