Analysis of malignant biology and gene disorder in gastric MALT lymphomas

由于粘膜相关淋巴组织（MALT）低级别b细胞淋巴瘤新实体的建立，对胃淋巴瘤进行了重新评价，并期待MALT淋巴瘤的最佳治疗方案。连续40例手术治疗的胃b细胞淋巴瘤经组织病理学重新分类为MALT淋巴瘤（n=26，低级别18例，高级别8例）和非MALT淋巴瘤（n=14），分析两组临床病理及预后，并进行比较研究。与非MALT淋巴瘤相比，MALT淋巴瘤患者术后无症状或症状模糊，不论是否发生高级别转化、是否累及淋巴结或术后化疗，其病史较长，预后较好。在仔细检查组织学之前，MALT淋巴瘤表现为范围较大，粘膜和粘膜下层的浅表扩散，以及肿瘤边缘的逃避。MALT淋巴瘤患者的5年生存率为94%，显著高于非MALT淋巴瘤的59%。然而，64%的高级别MALT淋巴瘤和59%的非MALT淋巴瘤之间没有显著差异。胃MALT淋巴瘤在生物学上应该与传统的非MALT淋巴瘤不同，因此迄今为止最佳的手术治疗方法是全胃切除术并2级淋巴结清扫。新近研究的幽门螺杆菌感染的MALT淋巴瘤发病机制将因此在未来的治疗方案的临床过渡。

Since new entity of low-grade B-cell lymphoma of mucosa associated lymphoid tissue (MALT) was established, re-evaluation of gastric lymphoma was carried on and optimal treatment protocol of MALT lymphoma has been anticipated. Consecutive 40 surgical cases of gastric B-cell lymphoma were histopathologically reclassified as MALT lymphoma (n=26 ; 18 low-grade and 8 high-grade) and non-MALT lymphoma (n=14), analyzed clinicopathologically including prognosis, and comparatively investigated between two groups. Compared to non-MALT lymphomas, patients of MALT lymphoma often presented no symptoms or vague symptoms with longer history and better prognosis after surgery irrespective of high-grade transformation, lymph node involvement or postoperative chemotherapy. MALT lymphomas exhibited larger extent, superficial spread of the mucosa and submucosa, and evasive margins of the tumor until scrutinized histology. 5-yr survival rate of patients with MALT lymphoma was 94%, significantly higher than 59% of non-MALT lymphoma. However, no significant difference was obtained between 64% of high-grade MALT lymphoma and 59% of non-MALT lymphoma. Gastric MALT lymphomas should be biologically different from conventional non-MALT lymphomas, leading to the optimal surgical treatment of total gastrectomy with level 2 lymph node dissection so far. Newly investigated pathogenesis of MALT lymphoma by Helicobacter Pylori infection would consequently take the clinical transitions of treatment protocol in the future.