The IPI score for lymphoma is based on the patient’s age, general status score, clinical stage, number of extra-lymph node invasion sites, and whether lactate dehydrogenase is normal. Age less than or equal to 60 years, general condition score of 0 or 1, clinical stage 1 or 2, number of extra-lymph node invasion sites less than 2, and lactate dehydrogenase within normal range are all scored as 0, and more than these are scored as 1. These scores are summed, and if they add up to 0 or 1, they are low risk; if they add up to 2, they are low intermediate; if they add up to 3, they are intermediate to high risk; if they add up to 4 or 5, they are high risk. This score can be used to guide the choice of treatment plan and to determine the prognosis, the better the score, the worse the prognosis.