Dogusoy G, Karayel F A, Göcener S, Göksel S
University of Istanbul, Cerrahpaşa Medical Faculty, Department of Pathology, Istanbul, Turkey.
Pathol Oncol Res. 1999;5(1):36-40. doi: 10.1053/paor.1999.0036.
The aim of this study is to present a histopathologic and immunohistochemical analysis of primary gastric lymphomas which were reclassified according to the concept of mucosa associated lymphoid tissue (MALT). The resected specimens from 41 patients with primary gastric lymphoma were investigated retrospectively. Immunohistochemical study was done to analyze the immunophenotype and bcl-2 and p53 proteins expression. Twenty three of the cases had tumors mainly located in the antrum. Histologically, 12 were low grade and 20 were high grade B-cell lymphoma of MALT, 9 other B-cell nonHodgkin's lymphomas. Helicobacter pylori was identified in 72% of the cases. According to Musshoff's modification, most of the MALT lymphoma cases had stage I or II disease. There was significant difference between low and high grade cases, in respect to depth of invasion in gastric wall. Immunohistochemically, the neoplastic cells in all MALT lymphomas expressed B-cell phenotype. Bcl-2 protein was found to be expressed in 59% and p53 protein expression was detected in 72% of cases. Among the B-cell lymphoma of MALT, bcl-2 positivity decreased and p53 positivity increased significantly as the histological grade advanced. So, an inverse correlation was observed between the expression of bcl-2 and p53. In conclusion, most primary gastric lymphomas are low or high grade B-cell MALT lymphomas and appear to arise in MALT acquired as a reaction to Helicobacter pylori infection. Expression of bcl-2 and p53 in gastric lymphomas may be associated with transformation from low-grade to high-grade disease.
本研究旨在对根据黏膜相关淋巴组织（MALT）概念重新分类的原发性胃淋巴瘤进行组织病理学和免疫组织化学分析。对41例原发性胃淋巴瘤患者的切除标本进行回顾性研究。进行免疫组织化学研究以分析免疫表型以及bcl-2和p53蛋白表达。其中23例肿瘤主要位于胃窦部。组织学上，12例为低度、20例为高度MALT型B细胞淋巴瘤，另外9例为B细胞非霍奇金淋巴瘤。72%的病例中检测到幽门螺杆菌。根据Musshoff改良法，大多数MALT淋巴瘤病例为Ⅰ期或Ⅱ期疾病。在胃壁浸润深度方面，低度和高度病例之间存在显著差异。免疫组织化学方面，所有MALT淋巴瘤中的肿瘤细胞均表达B细胞表型。59%的病例中发现bcl-2蛋白表达，72%的病例中检测到p53蛋白表达。在MALT型B细胞淋巴瘤中，随着组织学分级升高，bcl-2阳性率显著降低，p53阳性率显著升高。因此，观察到bcl-2和p53表达之间呈负相关。总之，大多数原发性胃淋巴瘤为低度或高度B细胞MALT淋巴瘤，似乎起源于因幽门螺杆菌感染而获得的MALT。胃淋巴瘤中bcl-2和p53的表达可能与疾病从低度向高度转变有关。
