Sorrentino D, Ferraccioli G F, Labombarda A, De Vita S, Avellini C, Beltrami C A, Bartoli E
Department of Internal Medicine, University of Udine, Italy.
Clin Exp Rheumatol. 1996 Jan-Feb;14 Suppl 14:S51-4.
MALT, or mucosa associated lymphoid tissue, is normally not present in gastric tissue. Its presence is often associated with persistent antigenic stimulation. MALT is a precursor of gastric MALT lymphoma, a low-grade lymphoma whose incidence recently appears to have increased. Although much epidemiologic and clinical evidence has linked both MALT and MALT lymphoma to Helicobacter pylori infection, it is not known whether other agents and or mechanisms may also play a role and whether there is a clearly defined pre-neoplastic lesion. In particular, the clinical significance of B-cell clonality remains unknown. In a recent study we attempted to define the role of H. pylori and MALT in the genesis of B-cell clonality in a northern Italian patient population referred to us for simple dyspepsia. The results show that B-cell clonality is unexpectedly frequent in these patients regardless of the presence of H. pylori infection. These observations raise the possibility that agents and mechanisms other than H. pylori may be involved in the genesis of MALT lymphoma. Indeed, other studies conducted by our group in patients with Sjögren's syndrome indicate that genetic/immunologic factors and possibly viruses may play a role. The high prevalence of B-cell clonality in an otherwise healthy population suggests either that most of these patients are at risk of developing MALT lymphoma (in which case this condition at the moment may be greatly underdiagnosed) or that B-cell clonality is a very early step in the development of neoplasia, which requires several other factors and which will occur only in a restricted fraction of these patients. Careful follow-up studies will provide an answer to this question.
黏膜相关淋巴组织（MALT），即黏膜相关淋巴样组织，在正常胃组织中并不存在。其出现通常与持续性抗原刺激有关。MALT是胃MALT淋巴瘤的前体，胃MALT淋巴瘤是一种低度淋巴瘤，其发病率近来似乎有所上升。尽管大量的流行病学和临床证据已将MALT及MALT淋巴瘤与幽门螺杆菌感染联系起来，但尚不清楚其他因素和/或机制是否也起作用，以及是否存在明确界定的肿瘤前病变。特别是，B细胞克隆性的临床意义仍不明确。在最近一项研究中，我们试图确定幽门螺杆菌和MALT在一群因单纯消化不良转诊至我们这里的意大利北部患者B细胞克隆性发生过程中的作用。结果显示，无论是否存在幽门螺杆菌感染，这些患者中B细胞克隆性的出现频率都出乎意料地高。这些观察结果增加了以下可能性，即除幽门螺杆菌外的其他因素和机制可能参与了MALT淋巴瘤的发生。实际上，我们小组对干燥综合征患者进行的其他研究表明，遗传/免疫因素以及可能的病毒可能起作用。在其他方面健康的人群中B细胞克隆性的高患病率表明，要么这些患者中的大多数有患MALT淋巴瘤的风险（在这种情况下，目前这种病症可能被严重漏诊），要么B细胞克隆性是肿瘤形成过程中非常早期的一个步骤，这需要其他几个因素，并且仅在这些患者中的一小部分中才会发生。仔细的随访研究将为这个问题提供答案。
