Why is further staging of lymphoma necessary? The purpose of staging is because the prognosis of different types of lymphoma varies, and clinical treatment differs. The current pathological criteria for the diagnosis of lymphoma are based on the 2008 WHO (World Health Organization) publication “Classification of Tumors of the Lymphoid Hematopoietic Tissue”. This classification is based on the cellular origin, including B cells and T/NK cells. The classification is very complex, with more than 20 types of mature B-cell lymphomas and nearly 20 types of T- and NK-cell lymphomas being the most common, making the diagnosis of pathology a great challenge. Pathologists require immunohistochemical staining for the diagnosis of lymphoma, and in many cases, molecular testing. Even so, a small number of patients cannot be diagnosed definitively and require further clinical observation. Therefore, it is recommended that all patients who come to the consultation should bring wax blocks or 15-20 white slices (unstained sections) to facilitate the diagnosis and help the pathologists make a more accurate diagnosis, so that clinicians can make more targeted treatment plans.