Romanian Journal of Morphology and Embryology 2010, 51(3):473–481 ORIGINAL PAPER The study of p53 and CA19-9 prognostic molecular markers in colorectal carcinomas GEORGETA AFREM 1) , ŞTEFANIA CRĂIŢOIU 2) , CL. MĂRGĂRITESCU 3) , S. S. MOGOANTĂ 4) 1) Department of Medical Expertise and Recovery of Work Capacity, Dolj 2) Department of Histology 3) Department of Pathologic Anatomy 4) Department of Surgery IV University of Medicine and Pharmacy of Craiova Abstract Immunohistochemistry represents a relatively new identification technique of cellular and tissular antigens due to an antigen–antibody binding interactions, applied more and more in the pathology laboratories for positive and differential diagnosis of premalignant and malignant lesions and also for evolutive prognosis of tumoral formations. Immunohistochemistry coloration is based on the antigen– antibody affinity, the antibody binding situs being identified either by antibody coloration direct methods or by using an indirect method where the marking is supplied by antibodies called secondary or even tertiary. The present study is based on the immunohistochemical investigation of some molecular markers with a prognosis value in colorectal cancers (CCR), like the antibody p53 immune expression and of some factors supposed to have prognosis value, such as CA19-9 (carcinoembryonic antigen, carbohydrate antigen or Lewis antigen). In the last decade, the studies have tried to define the prognosis of the molecular markers that allow the identification of the patients with recurrent risk after surgical treatment and who can benefit from chemotherapy in an efficient way. The purpose of the study on immunohistochemical markers is to aim towards the treatment based on molecular phenotypes of colorectal tumors. In 2000, according to the Consensus Conference of the Colorectal Working Group of the American Joint Committee on Cancer Prognostic Factors (AJC), there were established four categories of prognosis factors in colorectal cancers based on the practical importance and the number of studies referring to them. The present study is centered on the prognosis factors from the second B category (p53 oncoprotein expression) and the fourth category (CA19-9 immunomarker expression). Keywords: molecular markers in CCR, p53 antibody, CA19-9 antibody. Introduction According to the last world report in 2009 of the Cancer Statistics [1], colon cancer has an estimated incidence of 106 100 cases/year in both sexes (52 010 men and 54 090 women) and a number of 49 920 deaths/year in both sexes (25 240 men and 24 680 women). Globally, it is estimated that in both locali- zations (colon + rectum ), cancer is on third place regarding incidence both in men and in women, with a percentage of 10% of the total number of cancers and also on third place both in men and in women regarding the mortality rate , with 9% of the total cancer deaths. There was established that there was a significant statistical growth of incidence rates for colorectal cancer in both sexes between 1983–2002, apart from the USA, where there was established a decrease of the incidence in both sexes [2]. On average, the survival rate of one, three and five years is approximately of 90%, 78%, respectively 40–70%, and the free interval of the disease is approximately of 68 months [3]. Colorectal cancer is a multi factor disease, involving various etiopathology, whether we refer to a family aggregation, or to an exposure to a series of environ- mental risk factors (including nutrition), other times being involved a series of inflammatory causes of the digestive tract or the association between these risk factors. In the last decades, studies have tried to define the prognosis molecular markers that allow the identifi- cation of patients with a recurring risk after the surgical treatment and that may be eligible for effective chemo- therapy treatment. Some of these markers may predict whether a tumor responds to a certain type of chemo- therapy or it may predict the degree of the systemic toxicity for a certain type of treatment. In this direction, there was studied the individual expression of proteins and of some genes at the level of messenger RNA, by using PCR and immunohistochemistry techniques. The asserted purpose of some of these studies is to aim at the treatment based on molecular phenotypes of colorectal tumors in these patients [4]. From this point of view, our study was focused on the immunohistochemical investigation of some prog- nosis markers useful for therapy individualization in such patients.