| Theme |
Malignant Lymphoma of the GI Tract |
| Title |
The Concept and Differential Diagnosis of Lymphoma of Mucosa-Associated Lymphoid Tissue (MALT) and Reactive Lymphoid Hyperplasia (RLH) |
| Author |
Hideharu Miyabayashi |
The 2nd Department of Internal Medicine, Shinshu University School of Medicine / Endoscopic Division, Nagono Cancer Detection Center |
| Author |
Tsutomu Katsuyama |
Department of Laboratory Medicine, Shinshu University School of Medicine |
| [ Summary ] |
The concept of MALT lymphoma has abolished RLH with clearly tumorous growth, making RLH only part of the special inflammatory disorders at present. RLH is classfied as benign lymphoid hyperplasia (BLH) with severe infiltration of non-atypical lymphoid cells and a few inflammatory cells and atypical lymphoid hyperplasia (ALH) with a few atypical lymphoid cells and destruction of lymphoid follicle formation on histological findings.
Though it is difficult to differentiate RLH and MALT lymphoma of superficial type, specimens obtained by endoscopic mucosal resection are useful for histological diagnosis and molecular biological study,and flowcytometry or polymerase chain reaction for immunoglobulin heavy chain allow confirmation of B-cell proliferation. The borderline between low grade MALT lymphoma and RLH with atypical infiltration may not be clearly divisible, such that these borderline diseases may be judged as a state of gastric lymphoproliferative disease for determination of therapies and diagnositic methods. |