Lymphoma is cancer occurring in the lymphatic system. The condition occurs when the white blood cells are affected by the lymphatic cells as a result of which the entire lymph nodes get replaced by follicular lymphoma. Since lymphoma is present in the very blood stream, it has higher chances of spreading to other parts of the body or metastasizing. Lymphoma has treatments. Although it can affect people of all ages, it is most common in children and young adults between the ages of 15 to 24 years old.