P53与ras癌基因产物对直肠癌的诊断价值

目的提高直肠癌术前活检的诊断率。方法5年来手术治疗的168例直肠癌病人中，有20例（11．9％）第一次手术前活检不能明确诊断。对其中17例患者的活检组织石蜡标本（实验组）和10例正常肠粘膜活检标本（对照组）进行常规病理、P53与ras癌基因产物检测。结果实验组中P53与ras基因表达阳性率分别为71％与47％，阳性率均高于常规病理，有显著性差异。17例标本中，11例为不典型增生，5例仅有慢性炎症。不典型增生的P53与ras基因表达分别为11例和7例，而慢性炎症则全部为阴性。二者之间，两种基因表达阳性率均有显著差异。实验结果还显示P53与ras基因表达有较好的一致性。对照组的10例正常肠粘膜的活检标本P53与ras基因检测结果均阴性，与实验组比较，P53阳性率有显著差异。结论P53与ras基因表达检测，可以作为常规病理的补充，提高直肠良恶性病变的鉴别力。

Diagnostic Value of the Expression of Protein Products of Oncogene P53 and ras in Rectal Carcinoma

Objective To improve the diagnosis of the preoperative biopsy in rectal carcinoma. Methods Of 168 cases of rectal carcinoma that had been treated operatively in the past five years, 20 cases (11.9%) failed to be diagnosed definitely at their first preoperative biopsy. The paraffin specimens of biopsy tissues of 17 out of these 20 cases (experimental group) and those of 10 cases of normal rectal mucosa (control group) were examined by routine pathology, and the expression of protein products of oncogene P53 and ras. Results in the experimental group, the positive rates of P53 and ras expression were 71% and 47% respectively and were higher than those of the routine pathology, the differences being statistically significant. Among the examined specimens of the 17 cases, 11belonged to atypical hyerplasia and 5 were chronic inflammation only. The ntunber of positive expressions of P53 and ras were 11 and 7 cases in the atypical hyperplasia respectively, but they were all negative in the chronic inflammation. The differences between atypical hyperplasia and chronic inflammation were statistically significant. The resultS also showed that the expressions of P53 and ras oncogenes bore obvious uniformity. In the control group of 10 cases of normal rectal mucosa, the expressions of P53 and ras were all negative. The dfference of positive rates of P53 expression between experimental group and control group was significant. Conclusions The techniques of detecting the expressions of protein products of oncogene P53 and ras can be a supplementary means of routine pathology to improve the diagnosis of the biopsy to rectal carcinoma.