• Stage 2A: AThe tumor is confined to one area, but has not been completely resected macroscopically. No histologic metastasis is found in lymph nodes outside the tumor on the same side of the body.
• Stage 2B: BThe tumor is confined to one area, and it may or may not be possible to completely resect it macroscopically . It has spread to lymph nodes outside the tumor on the same side of the body, but no histologic metastasis is found in lymph nodes on the other side of the body.

• The tumor cannot be completely resected and has crossed the midline to the other side of the body. It may or may not have spread to local lymph nodes on the same side of the body.
• The tumor is confined to one area but has spread to lymph nodes on the other side of the body.
• The tumor is in the middle of the body, is growing toward both sides and cannot be completely resected, or has spread to lymph nodes on both sides of the body.

The tumor has spread to either of the following distant sites: distant lymph nodes, bone, bone marrow, liver, skin, or other organs (excluding tumors of stage 4S).

The child is younger than 1 year old. The primary tumor is localized (defined as Stage 1, 2A, or 2B). The tumor has spread to the skin, liver, and/or the bone marrow. Although distant metastasis is found, tumors in infants respond well to treatment and some undergo spontaneous regression. The prognosis is favorable.