How is neuroblastoma diagnosed?
Although neuroblastoma may be present at birth, a diagnosis usually is not made until the cancer has grown enough to produce symptoms. At this point, however, the disease may have also spread to other parts of the body. Your child's doctor will perform a complete physical examination. If the tumor is large enough, he or she may be able to feel it in the abdominal area. If your doctor suspects a neuroblastoma, he or she will order tests that scan the chest and abdomen, such as
computed tomography (CT) and magnetic resonance imaging (MRI). If these tests reveal any tumors, your doctor will want to take a small tissue sample, called a biopsy, from the tumor to examine under a microscope. Determining whether and how far the cancer has spread from its original location is called "staging," and helps determine treatment. The stages of neuroblastomas are classified as localized resectable, localized unresectable, regional, disseminated, or stage IV. A localized resectable neuroblastoma has not spread to other tissues and can be surgically removed in its entirety. A localized unresectable neuroblastoma has not spread to other tissues, but can't be completely removed surgically. A regional neuroblastoma has spread to the lymph nodes, as well as other organs and/or tissues in the area immediately around the original tumor, but hasn't spread to more distant areas of the body. Disseminated neuroblastoma has spread to more distant areas of the body, including the lymph nodes and the bone, liver, skin, bone marrow, and/or other organs. Type IV neuroblastoma, also called ÒspecialÓ neuroblastoma, has spread only to the liver, skin, and/or to a limited portion of the bone marrow. Neuroblastoma that is diagnosed as recurrent continues to spread after treatment, or comes back at a later time.
A staging system has been developed for neuroblastoma to help the physician determine the best treatment for the disease. The stage is based on how far the disease has spread from its original site. In stage 1, the cancer is found only in the place where it started. In stage 2a, the cancer is on one side and can only be partially removed. It has not spread to the lymph nodes. In stage 2b, there is cancer on one side with complete or incomplete removal but with lymph nodes that are positive for spread from the same side. It has not spread to lymph nodes on the other side of the body. In stage 3, the cancer has spread to tissues on the other side of the body and/or it has spread to lymph nodes relatively near the original cancer but on the other side of the body. Stage 4 indicates that the cancer has spread to distant lymph nodes, bone, liver, skin, bone marrow or other organs. Finally, stage 4 indicates that the primary tumor has not directly spread to the opposite side of the body. Lymph nodes on the same side of the body may be involved, but nodes on the other side are not involved. Neuroblastoma may have spread to the liver or skin and may involve the bone marrow.