结直肠癌及癌前病变中DNA倍体分析及其临床意义

Clinical Significance of DNA Ploidy in Patients with Colorectal Carcinoma and Its Precancerous Lesions

目的:检测结直肠癌及癌前病变细胞内的DNA含量及DNA指数,探讨其辅助诊断和预测癌变危险度的意义。方法:应用流式细胞仪(FCM)对400例结直肠组织细胞的细胞核进行DNA倍体分析,其中正常结直肠黏膜组30例,增生性息肉组30例,绒毛状腺瘤组190例,结直肠癌组150例,检测其异倍体检出率和DI值。结果:结直肠癌组的DNA异倍体检出率显著高于正常直肠黏膜组3、增生性息肉组及绒毛状腺瘤组(P<0.01),绒毛状腺瘤伴重度不典型增生组的DNA异倍体检出率显著高于正常直肠黏膜组3、增生性息肉组、无不典型增生的绒毛状腺瘤组及伴轻度、中度不典型增生的绒毛状腺瘤组(P<0.01)。随着结直肠癌的组织学分化程度降低,其DNA异倍体DI值呈增加趋势并有显著性差异(P<0.01)。结论:DNA含量和倍体的检测有助于了解肿瘤细胞的增殖情况及恶性程度,对诊断结直肠良恶性肿瘤、预测癌变危险度、判断预后均具有重要的参考价值。

Objective： To investigate the diagnostic value of DNA content and DNA index for patients with colorectal carcinoma and its precancerous lesions. Methods： Flow cytometry was used to measure DNA ploidy in fresh colorectal tissues from 400 cases including 150 patients with colorectal cancer, 30 patients with proliferative polyps, 190 patients with villous adenoma and 30 normal controls. The positive rates of heteroploidy and DNA index （DI） were analyzed. Results： The positive rate of heteroploidy in colorectal carcinoma was much higher than that in proliferative polyps, villous adenoma and normal controls （P〈0.01）. The positive rate of heteroploidy in villous adenoma with major atypical proliferation was much higher than that in proliferative polyps, normal controls, villous adenoma without atypical proliferation, villous adenoma with mild atypical proliferation and villous adenoma with moderate atypical proliferation （P〈0.01）. When the histological differentiation degree of colorectal cancer decreased, the index of DNA heteroploidy gradually increased and the difference was significant （P〈0.01）. Conclusion： DNA content and DNA ploidy are valuable indicators of the proliferation potential and degree of malignancy in tumor cells. The detection of DNA ploidy is helpful for determin- ing the diagnosis and prognosis of colorectal tumors, in addition to predicting carcinogenesis.