Chronic inflammation, while originally a protective physiological response, is increasingly recognized as a key contributor to carcinogenesis. Prolonged inflammatory signaling leads to the sustained production of reactive oxygen and nitrogen species (ROS/RNS), resulting in direct and indirect DNA damage, including base modifications, strand breaks, and DNA cross-linking. Simultaneously, pro-inflammatory mediators such as NF-κB, IL-6, and TNF-α can interfere with DNA repair mechanisms, altering the efficiency of key pathways such as base excision and mismatch repair. Immune cells infiltrating chronically inflamed tissues, including macrophages and neutrophils, further exacerbate genomic instability through ROS/RNS release and cytokine production, creating a tumor-promoting microenvironment. Additionally, chronic inflammation has been implicated in the development of resistance to chemotherapy and radiotherapy by modulating DNA damage response pathways. Understanding the interplay between inflammation, genomic instability, and therapy resistance provides a framework for novel treatment strategies. Targeting chronic inflammation with non-steroidal anti-inflammatory drugs (NSAIDs), corticosteroids, or biological agents such as monoclonal antibodies offers promising avenues for cancer prevention and treatment. Targeting inflammation with NSAIDs, corticosteroids, and monoclonal antibodies shows promise in cancer prevention and therapy, particularly in lung and pancreatic cancer. These agents act by blocking key inflammatory pathways like COX-2, NF-κB, and cytokine signaling. However, potential adverse effects require further clinical evaluation.