PROGNOSTIC BIOMARKERS OF GASTROINTESTINAL NEOPLASIA

Abstract

In the era of personalized treatment, oncologists are striving to tailor medical treatment to the characteristics of the individual patient, emphasizing the importance of a continuous search for accurate biomarkers. Prognostic biomarkers reflect the intricate underlying biology that enables cancer to progress. Intratumoral heterogeneity includes genetic, epigenetic and functional heterogeneity. Genetic intratumoral heterogeneity is a consequence of clonal evolution and a cause of disease progression. During the oncogenesis process, genetic aberrations accumulate continuously, result of this process is that tumors are genetically heterogeneous, with a plurality of coexisting clones that vary over time. Herewith specific mutations are associated with particular stages of tumor development, correlates with specific histopathological disease stages. Many patients with colorectal cancer have disease recurrence after resection of the tumor despite adjuvant therapy, while some patients don’t have a relapse despite the absence of treatment. Identifying reliable predictors of outcome after resection is a universal problem. So the reassessment of the current criteria and better prognostic and predictive biomarkers for the selection of patients who might benefit from adjuvant chemotherapy are urgently needed. A prognostic biomarker reflects the natural history of the tumor and provides information on the likely outcome and prognosis, independent of a specific treatment. Predictive biomarkers indicate the sensitivity or resistance of the tumor to a given treatment. Some markers can be both prognostic and predictive. Gene mutations and epigenetic aberrations that modify the intracellular signaling pathways may be important factors in oncogenesis. In this context, oncogenes, genes – tumor suppressors and small non-coding RNA have attracted attention as potential biomarkers and regulators of oncogenesis and evaluate in clinical trials.