Li Bai-zhou, Lu Hong-fen, Zhou Xiao-yan, Yang Wen-tao, Kong Yun-yi, Fan Yue-zhen, Shi Da-ren
Department of Pathology, Cancer Hospital of Fudan University, Department of Oncology, Shanghai Medical College of Fudan University, Shanghai 200032, China.
Zhonghua Bing Li Xue Za Zhi. 2008 Sep;37(9):604-8.
To study the frequency of certain specific genetic aberrations, including t (11; 18)/API2-MALT1, t (1; 14)/IgH-bcl-10 and t (14; 18)/IgH-MALT1, in mucosa-associated lymphoid tissue (MALT) lymphoma of different sites.
One hundred and ninety-six cases of MALT lymphoma from Cancer Hospital of Fudan University were enrolled into the study. The samples consisted of MALT lymphomas from stomach (53 cases, including 44 cases of low-grade MALT lymphoma and 9 cases of MALT lymphoma with diffuse large B-cell lymphoma component), ocular adnexa (50 cases), salivary gland (20 cases), lung (20 cases), intestine (17 cases), skin (17 cases), liver (8 cases), thyroid (5 cases) and other sites (2 cases from tongue, 1 case from pancreas, 1 case from larynx, 1 case from vocal cords and 1 case from kidney). Fluorescence in-situ hybridization for API2-MALT1 fusion gene, bcl-10, MALT1 and IgH genes was performed on paraffin sections.
Among the 196 cases of MALT lymphoma, 25 cases (12.8%) possessed API2-MALT1 fusion gene. The positive rates in various sites were significantly different (P = 0.002), as follows: 45.0% (9/20) in lung, 22.7% (10/44) in stomach (without large cell component), 15.0% (3/20) in salivary gland, 2 of 17 cases in intestine and 2.0% (1/50) in ocular adnexa. The fusion gene was not detected in the 9 cases of gastric MALT lymphoma with large cell transformation. It was also negative in the MALT lymphomas from skin, thyroid and other sites. One of the pulmonary MALT lymphoma cases showed simultaneous aberrations of IgH and MALT1 genes, such as t (14; 18)/IgH-MALT1. Two of the gastric MALT lymphoma cases without large cell transformation and one of the pulmonary MALT lymphoma cases showed aberrations in both IgH and bcl-10 genes, such as t (1; 14)/IgH-bcl-10. Six cases of MALT lymphoma, including 2 cases from salivary gland, 2 cases from liver, 1 case from thyroid and 1 case from stomach (large cell transformation), showed trisomy 18. On the other hand, 3 cases, including 2 cases from stomach and 1 case from intestine, showed MALT1 gene amplification.
In general, specific genetic aberrations have a relatively low frequency of occurrence in MALT lymphomas. The positive rates however show a remarkable difference in tumors of different anatomic sites. This phenomenon may suggest that MALT lymphomas in different sites, though sharing similar morphologic features, may have a divergent tumorgenesis.
研究特定基因畸变，包括t(11;18)/API2-MALT1、t(1;14)/IgH-bcl-10和t(14;18)/IgH-MALT1在不同部位黏膜相关淋巴组织（MALT）淋巴瘤中的发生频率。
纳入复旦大学附属肿瘤医院196例MALT淋巴瘤病例。样本包括来自胃的MALT淋巴瘤（53例，其中44例为低级别MALT淋巴瘤，9例为伴有弥漫性大B细胞淋巴瘤成分的MALT淋巴瘤）、眼附属器（50例）、唾液腺（20例）、肺（20例）、肠（17例）、皮肤（17例）、肝（8例）、甲状腺（5例）及其他部位（舌2例、胰腺1例、喉1例、声带1例、肾1例）。对石蜡切片进行API2-MALT1融合基因、bcl-10、MALT1和IgH基因的荧光原位杂交检测。
196例MALT淋巴瘤中，25例（12.8%）存在API2-MALT1融合基因。各部位阳性率差异有统计学意义（P = 0.002），具体如下：肺45.0%（9/20）、胃（无大细胞成分）22.7%（10/44）、唾液腺15.0%（3/20）、肠17例中有2例、眼附属器2.0%（1/50）。9例伴有大细胞转化的胃MALT淋巴瘤未检测到融合基因。皮肤、甲状腺及其他部位的MALT淋巴瘤也为阴性。1例肺MALT淋巴瘤病例显示IgH和MALT1基因同时畸变，如t(14;18)/IgH-MALTl。2例无大细胞转化的胃MALT淋巴瘤病例和1例肺MALT淋巴瘤病例显示IgH和bcl-10基因均有畸变，如t(1;14)/IgH-bcl-10。6例MALT淋巴瘤，包括唾液腺2例、肝2例及甲状腺和胃（大细胞转化）各1例，显示18号染色体三体。另一方面，3例，包括胃2例和肠1例，显示MALT1基因扩增。
总体而言，特定基因畸变在MALT淋巴瘤中的发生率相对较低。然而，不同解剖部位肿瘤的阳性率存在显著差异。这一现象可能提示不同部位的MALT淋巴瘤尽管形态学特征相似，但可能具有不同的肿瘤发生机制。
