TP53 and diffuse large B-cell lymphoma: Although current studies often define abnormal p53 expression patterns as either diffuse strong positivity in nearly all tumor cells (overexpression pattern) or a complete absence (null pattern) to indirectly reflect underlying TP53 mutation status, several studies have indicated that even lower immunohistochemical positivity thresholds (such as > 10% or 20%) for p53 expression can still significantly predict survival outcomes in patients with DLBCL [26, 49].