Globally, more than one million new cases of gastric cancer are anticipated by 2024, representing a significant unmet clinical need. It is the fourth most prevalent cancer in men and the seventh most prevalent cancer in women. The pathogens Helicobacter pylori (H. pylori) and Epstein-Barr virus (EBV) have been linked to a significant number of cases of gastric cancer. On the other hand, the recorded results were not particularly impressive because the gastrointestinal tract (GI) is frequently diagnosed at a very advanced stage, traditional treatments are not very effective, and they have several adverse side effects. In the pursuit of improved systemic therapy, the use of targeted medications has greatly benefited GI care. Immunotherapies, vascular endothelial growth factor, epidermal growth factor receptor, and human epidermal growth factor receptor-2 obstruct the programmed death receptor 1/programmed death-ligand 1 pathway. Advanced gastrointestinal tract (GI) malignancies are increasingly treated at the molecular level. Extended gene RAS and BRAF testing were required to predict the efficacy of trastuzumab (HER2-targeted therapy) and pembrolizumab (anti-PD-1 therapy) for metastatic gastroesophageal (GEJ) malignancies. For metastatic colorectal malignancies, extensive RAS and BRAF testing is required to predict the efficacy of EGFR-targeted therapies. Mismatch repair (MMR) or microsatellite instability (MSI) testing must be performed on all advanced gastrointestinal (GI) malignancies to determine if pembrolizumab or nivolumab with or without ipilimumab will be effective. These advanced tumors are treated with targeted drugs for GI malignancies, and it is now common knowledge that patients must be identified through routine molecular profiling. This article provided a clinical summary of the most recent advances in targeted treatment for GEC and the supporting clinical data, such as their efficacy and safety profiles.