Final answer:
Radiation from nuclear medicine can potentially cause cancer due to alterations in DNA that may lead to cancerous mutations, but the risk is generally low, especially with targeted radiotherapy that aims to maximize the therapeutic ratio and minimize exposure to normal tissue.
Step-by-step explanation:
The radiation delivered by nuclear medicine has a small chance of causing cancer because it involves radioactive emissions that can damage living tissues, specifically DNA within cells potentially promoting cancer if the DNA damage leads to mutations. Radiation therapy is a treatment that uses high-energy radiation to kill cancer cells by damaging their DNA, but unfortunately, it can also affect normal cells. The risk of inducing cancer from radiation is linked to the dose and quality of radiation. A principle known as the linear hypothesis suggests that there is no safe level of radiation and that even low doses might increase the risk of cancer, though the risk at low doses is small and some researchers argue that it might be overestimated or even beneficial (hormesis).
Furthermore, radiotherapy techniques strive to maximize the therapeutic ratio, which is the ratio of abnormal cells killed to normal cells affected, to minimize collateral damage to healthy tissues. Radiopharmaceuticals are a more targeted approach where radioisotopes are attached to antibodies, concentrating the radiation in cancerous tissue and thereby potentially reducing exposure to normal tissue. However, there is still a risk involved since organs responsible for eliminating these substances can receive a significant dose of radiation.