Krugmann J, Tzankov A, Dirnhofer S, Fend F, Greil R, Siebert R, Erdel M
Institute of Pathology, University of Innsbruck, Müllerstrasse 44, A-6020 Innsbruck, Austria.
J Clin Pathol. 2004 Apr;57(4):360-4. doi: 10.1136/jcp.2003.012369.
The most frequent cytogenetic alteration in gastrointestinal (GI) B cell lymphoma (BCL) is t(11;18)(q21;q21). GI B cell non-Hodgkin lymphomas lacking this translocation vary in their biology and clinical outcome. The t(11;18) negative subgroup shows increased numerical changes of chromosome 18, although its clinical relevance remains unknown.
Thirty surgically resected primary GI BCLs were examined-11 low grade marginal zone mucosa associated lymphoid tissue (MALT) lymphomas, four marginal zone lymphomas with diffuse large BCL (DLBCL), and 15 de novo DLBCLs. Chromosome 18 aberrations were examined using interphase fluorescence in situ hybridisation. Trisomy 18 was studied applying a centromere 18 probe and a dual colour probe for the MALT1 gene at 18q21.
Using the MALT1 probe, only one marginal zone MALT lymphoma had a break apart pattern, indicating t(11;18) or variants. In the GI BCLs lacking MALT1 breaks, trisomy 18q21 was seen in seven patients (four with complete trisomy 18 and three with partial trisomy of 18q21). Trisomy 18q21 was found in two of 10 low grade MALT lymphomas and five of 19 GI BCLs with large cell component. Six of 17 patients with trisomy 18q21 presented with >/= stage II and one of 12 with stage I disease. Trisomy 18q21 was associated with significantly shorter disease specific survival in the whole group and GI BCLs with large cell component, but not in the low grade group.
Trisomy 18q21, including MALT1, may be associated with advanced tumour stage and may be a predictor of poor outcome in surgically resected primary GI BCLs.
胃肠道（GI）B细胞淋巴瘤（BCL）中最常见的细胞遗传学改变是t(11;18)(q21;q21)。缺乏这种易位的胃肠道B细胞非霍奇金淋巴瘤在生物学特性和临床结局方面存在差异。t(11;18)阴性亚组显示18号染色体的数目改变增加，但其临床相关性尚不清楚。
对30例手术切除的原发性胃肠道BCL进行检测，其中11例为低级别边缘区黏膜相关淋巴组织（MALT）淋巴瘤，4例为伴有弥漫性大B细胞淋巴瘤（DLBCL）的边缘区淋巴瘤，15例为原发性DLBCL。采用间期荧光原位杂交技术检测18号染色体畸变。应用18号染色体着丝粒探针和18q21处MALT1基因的双色探针研究18号染色体三体。
使用MALT1探针时，仅1例边缘区MALT淋巴瘤出现断裂模式，提示存在t(11;18)或其变异型。在缺乏MALT1断裂的胃肠道BCL中，7例患者出现18q21三体（4例为完整的18号染色体三体，3例为18q21部分三体）。10例低级别MALT淋巴瘤中有2例、19例伴有大细胞成分的胃肠道BCL中有5例发现18q21三体。17例18q21三体患者中有6例表现为II期及以上，12例I期疾病患者中有1例。18q21三体在整个研究组以及伴有大细胞成分的胃肠道BCL中与疾病特异性生存期显著缩短相关，但在低级别组中并非如此。
包括MALT1在内的18q21三体可能与肿瘤晚期相关，并且可能是手术切除的原发性胃肠道BCL预后不良的一个预测指标。
