Diez M, Medrano M, Mugüerza J M, Ramos P, Hernandez P, Villeta R, Martín A, Noguerales F, Ruiz A, Granell J
Hospital Principe de Asturias, Alcalá de Henares, 28808 Madrid, Spain.
Anticancer Res. 2000 Sep-Oct;20(5C):3907-12.
The prevalence of genetic alterations is different in primary carcinomas from the proximal colon when compared with carcinomas from the distal colorectum. The objective of this work was to explore the existence of possible differences in the informative weight of the risk of tumor recurrence provided by p53 immunostaining depending on the localization of the neoplasm.
Nuclear immunohistochemical expression of p53 protein was determined in formalin-fixed paraffin-embedded archival tumor tissue samples from 190 primary colorectal adenocarcinomas. The relative prognostic importance on the risk of recurrence of each variable was assessed in a Cox's proportional hazard regression analysis. Multiplicative interaction terms between p53 and tumor site were included in the multivariate models in order to test their joint effect on survival.
One hundred and one patients (53.1%) manifested nuclear accumulation of the protein. P53 overexpression was more frequent in distal than in proximal tumors (58.5% ve s 41.7%) (p = 0.03). Disease-free survival was lower in p53-positive cases (75% versus 38%) (p = 0.006), but significance of the association varied according to the localization of the tumor (p = 0.004 in proximal carcinomas and p = 0.049 in distal carcinomas). Multivariate analysis identified p53 positivity and distal tumor localization as the factors significantly associated with a high risk of recurrence Interaction between p53 expression and localization was present. P53 exhibited different prognostic value in distal and proximal colon. While adjusted hazard ratio for positive p53 was 1.99 in distal cancers, it was 8.04 for proximal tumors.
The prognostic with value of tumor recurrence associated overexpression of p53 protein is influenced by the location of the tumor. The negative predictive weight is significantly higher in proximal than in distal cancers.
与远端结直肠癌相比，近端结肠癌中原发性癌基因改变的发生率有所不同。本研究的目的是探讨根据肿瘤定位，p53免疫染色提供的肿瘤复发风险信息权重是否存在差异。
在190例原发性结直肠癌的福尔马林固定石蜡包埋存档肿瘤组织样本中，测定p53蛋白的核免疫组化表达。在Cox比例风险回归分析中评估每个变量对复发风险的相对预后重要性。多变量模型中纳入了p53与肿瘤部位之间的相乘交互项，以检验它们对生存的联合效应。
101例患者（53.1%）表现出该蛋白的核蓄积。p53过表达在远端肿瘤中比近端肿瘤更常见（58.5%对41.7%）（p = 0.03）。p53阳性病例的无病生存率较低（75%对38%）（p = 0.006），但这种关联的显著性因肿瘤定位而异（近端癌中p = 0.004，远端癌中p = 0.049）。多变量分析确定p53阳性和远端肿瘤定位是与高复发风险显著相关的因素。p53表达与定位之间存在相互作用。p53在远端和近端结肠中表现出不同的预后价值。在远端癌中，p53阳性的调整风险比为1.99，而在近端肿瘤中为8.04。
p53蛋白过表达与肿瘤复发相关的预后价值受肿瘤位置影响。近端癌的阴性预测权重显著高于远端癌。
