Onkogeeniset refers to substances or agents that can cause cancer. The term originates from the Greek word "onkos," meaning mass or tumor, and "genesis," meaning origin. Onkogeeniset agents can be diverse, encompassing various factors that contribute to the development of malignant neoplasms. These can include certain chemicals found in tobacco smoke, industrial pollutants, and even some naturally occurring toxins. Viruses, such as human papillomavirus (HPV) and hepatitis B virus (HBV), are also considered onkogeeniset as they can integrate their genetic material into host cells, disrupting normal cellular processes and leading to uncontrolled cell growth. Radiation, both ionizing (like X-rays and gamma rays) and non-ionizing (like ultraviolet radiation from the sun), can damage DNA and increase the risk of cancer. Genetic predispositions, where individuals inherit specific gene mutations, can also make them more susceptible to developing cancer, though these are not typically classified as external onkogeeniset agents. Understanding onkogeeniset factors is crucial for cancer prevention, early detection, and the development of targeted therapies. Research into the mechanisms by which these agents induce cancer continues to be a major focus in oncological studies.