CR2 and neoplasm: Additionally, immunohistochemistry for markers of B lymphocyte or non-germinal center lymphocyte (CD20, CD79a, PAX5), markers of reactive T lymphocytes surrounding tumor cell of MALT (CD3, CD5, CD8) and indicators for differential diagnosis of primary renal MALT lymphoma and other blood system tumors (CD21, CD23, BCL-6, and CD10) contributed to explore abnormal changes in terms of molecular pathology.