| 特集名 | 大腸のリンパ増殖性病変の現状 -- 悪性リンパ腫を中心に | |
|---|---|---|
| 題名 | 病理 (総説) (4) 悪性リンパ腫との鑑別を要するリンパ増殖性病変 (非腫瘍性) | |
| 発刊年月 | 2004年 09月 | |
| 著者 | 二村 聡 | 東京慈恵会医科大学病理学講座 |
| 著者 | 池上 雅博 | 東京慈恵会医科大学病理学講座 |
| 【 要旨 】 | 要旨はありません。 | |
| Theme | Present status of lymphoid proliferative disease of the colo-rectum with special reference to malignant lymphoma | |
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| Title | Benign lymphoproliferative disorders and differential diagnoses | |
| Author | Satoshi Nimura | Department of Pathology, the Jikei University School of Medicine |
| Author | Masahiro Ikegami | Department of Pathology, the Jikei University School of Medicine |
| [ Summary ] | The gastrointestinal tract normally contains large quantities of lymphoid tissue in the form of primary lymph nodules, secondary lymph nodules (lymph follicles), Peyer's patches, and individual cells within the lamina propria mucosae. Lymphoid aggregates are frequently stimulated to develop germinal centers for antibody production. A majority of lymph follicles display germinal centers polarized into two zones : a light-staining zone that faces the lamina propria mucosae, composed predominantly of small cleaved cells and antigen-presenting dendritic cells ; and a dark-staining zone at the opposite pole of the lymph follicle and farthest from the mucosal surface, composed of non-cleaved large cells. A high rate of mitosis, apoptotic cells, and tigible body macrophages are present in the dark zone. The mantle zone is often wider around the light rather than the dark zone. Presence of polarity (i.e. dark and light zones) is a useful finding for differential diagnoses between benign lymphoid hyperplasia and follicular lymphoma. Moreover, immunohistochemical staining for bcl-2 proteins in paraffin sections resolves the diagnostic dilemma. The neoplastic cells in the vast majority of cases of follicular lymphoma express bcl-2 proteins, whereas the cells in benign germinal centers do not. A potential pitfall in these interpretations is the presence of bcl-2-positive T-cells, which sometimes are seen in substantial numbers in benign germinal centers. Correlation of morphologic features with a clinical history and results of ancillary studies, such as immunohistochemistry, serologic tests, cultures, and genetic analysis, may be helpful in differentiating benign lymphoproliferative disorders from malignant lymphomas. |
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