Immunohistochemistry predictive markers for primary colorectal cancer tumors: where are we and where are we going?

The aim of our study is to highlight and organize the recently published immunohistochemistry (IHC) predictive biomarkers of primary colorectal cancers (CRCs) that could lead to practical implementation. We reviewed articles that examined CRC samples with significant statistic correlation between the IHC marker expression and disease progression over time, relationships with the available clinical features and those who detect the prognosis of drug effects. Our analysis showed that nine markers could correlate with medical treatment response of CRCs in different stages. When using better overall survival (OS) and better disease-free survival (DFS) as a grouping factor, there were 14 markers that could be used in assessing CRC prognosis. By using poor prognostic for the OS and the DFS as a grouping factor, we found 43 markers. Subgroup analysis was also performed based on the 32 markers recently confirmed to predict metastasis evolution or the recurrence risks. Venous invasion could be predictable for tumors, statistically significant metastasis susceptibility was observed for markers and also the capacity to evaluate recurrence. CRCs integrate a variety of localizations and there are proofs that distinguish the sites of tumors. The studies reporting data specifically for rectal cancer separating it from colon cancer contained seven IHC markers. In order to be able to implement a predictive biomarker in clinical practice, it must comply with certain criteria as clinical value and analytical proof. Unique biological signature of CRC can be distinguished by identifying biomarkers expression. Several markers have shown potential, but the majority still need to render clinical utility.

Colon cancer: clinical, macroscopic and microscopic aspects.

Although in developed countries the incidence of colorectal cancer is decreasing through the introduction of well-designed screening systems, the worrying worldwide increase of the mortality rate by colorectal neoplasm indicates the need for a thorough characterization of this pathology. Clinical, endoscopic, histopathological and immunohistochemical data provide important information for creating categories of patients that can benefit from intensive screening methods and for establishing the prognosis based on these data. Approximately 80% of the colorectal cancer develops from adenomas, which shows that early detection of premalignant lesions is an important step in reducing global incidence and mortality. Our study aims at providing information about the clinical, imaging and histopathological characterization of colorectal neoplasm and premalignant lesions. A total of 98 patients were evaluated, including 72 patients diagnosed with colorectal cancer and 26 with premalignant lesions. Patients underwent colonoscopy with biopsy specimens that were examined histopathologically. From the epidemiological data, we observe a higher incidence in men with a men/women ratio of 2/1, with a median age in colorectal cancer patients of 63.93 years. Different data on signs and symptoms were observed according to the colonoscopy location, with a slight difference between symptoms of patients with premalignant lesions compared to those diagnosed with colorectal neoplasm. Endoscopy showed that the rectum was the most frequent location, followed by the left colon, the tumor having a vegetative aspect in most cases. Histopathology confirms that the most common subtype is adenocarcinoma, described in 67 of the studied cases. The moderate differentiation degree is present in more than half of the cases.