多原发大肠癌微卫星不稳定性的研究

Microsatellite instability in multiple primary colorectal cancers

目的探讨微卫星不稳定性（ＭＳＩ）在多原发及单发大肠癌中的变化规律方法应用ＰＣＲ－ＳＳＣＰ技术对２４例多原发大肠癌和对照２１例单发大肠癌石蜡组织切片提取ＤＮＡ，并进行染色体不同位点微卫星不稳定性基因标志的检测结果多原发大肠癌中微卫星不稳定性的发生率为７１％（１７／２４），单发大肠癌微卫星不稳定性的发生率为３８％（８／２１），二者有明显差异（Ｘ２＝６．８２，Ｐ＜０．０２）ＭＳＩ阳性的多原发大肠癌主要发生在年轻的男性患者，与单发大肠癌相比（ｘ２＝４．６４，Ｐ＜０．０５），有统计学意义．多原发大肠癌ＭＳＩ阳性癌肿在右半结肠发生率及分布在ＤｕｋｅｓＡ，Ｂ期居多，但与单发大肠癌相比并无明显差异结论微卫星不稳定性在多原发大肠癌的发生发展中起重要作用。

AIM To study the changeable patterns of microsatelliteinstability (MSI) in multiple primary colorectal carcinomas(MPCC) and solitary colorectal tumors.METHODS Silver staining single strand con formationpolymorphism-polymerize chain reaction (PCR-SSCP ) wasused to screen MSI markers at 4 loci on chromosome 2, 5and 17 in paraffin--embedded tissues of MPCC (n = 24) andsolitary colorectal tumors (n=21).RESULTS The abnormal shifting of the single--strand DNAwas identified in 17 (71 % ) out of 24 cases of MPCC, and 8(38% ) out of 21 cases of solitary colorectal tumors. Frequency of positive MSI in MPCC was significantly higherthan that in the solitary tumors (P < 0 .05). Young malepatients, tumors located in the right--side colon, andDukes A and B stages were more commonly found in MPCCthan in the solitary tumors, but there was no significantdifference.CONCLUSION MSI may play an imPOrtant role in MPCCcarcinogenesis, development, and might be used as anadditional marker for the diagnosis of MPCC in the largebowel.