摘要目的进一步限定壶腹周围肿瘤染色体9p21区域缺失范围。方法选择染色体9p21区域5个微卫星多态性标记，通过聚合酶链反应、聚丙烯酰胺凝胶电泳和银染法，检测35例壶腹周围肿瘤组织及其外周血杂合性丢失（LOH）状况。结果 50%（4/8）胰腺癌有至少一个微卫星位点的LOH，其中D9S974（37.5%）和D9S942（28.6%）丢失频率较高，并且有连续性丢失现象。62.5%（5/8）壶腹癌在部分或全部位点出现LOH，其中D9S942（42.9%）丢失频率最高，其次为IFNA（37.5%）和D9S171（37.5%）。14.2%（1/7）胰岛素瘤有一个位点LOH。结论壶腹周围肿瘤染色体9p21最小共同缺失区位于D9S974和D9S942位点之间，距离小于15kb，其中可能存在一个新的涉及该肿瘤发生的相关抑癌基因。

abstractsObjective　To further define the extent of chromosome 9p21 deletion in periampullary neoplasms.Methods　The loss of heterozygosity at 5 microsatellite polymorphic markers on chromosome 9p21 was detected by polymerase chain reaction (PCR), polyacrylamide gel electrophoresis (PAGE) and silver staining in 35 specimens of periampullary neoplasms and their matching blood samples.Results　Fifty percent (4/8) of pancreatic cancer cases showed the loss of heterozygosity at one or more microsatellite loci, with the more frequent sites of D9S974 (37.5%) and D9S942 (28.6%), and some showing consecutive allelic loss. Sixty-two point five percent (5/8) of ampullary carcinoma cases showed loss of heterozygosity at one or more of the loci, frequent site of loss being D9S942 (42.9%) and the next most frequent being IFNA (37.5%) and D9S171 (37.5%). Loss of one locus was observed in 14.2% (1/7) of insulinoma. Conclusion　The minimal common region of chromosome deletion in periampullary neoplasms is defined between the D9S974 and D9S942 loci within a 15?kb interval in 9p21, suggesting the involvement of a novel tumor suppressor gene in their carcinogenesis.