Cancer is not a parasite in the traditional sense, as it is not an organism that lives in or on another organism and derives its nourishment from it. However, some scientists have proposed that cancer cells share certain characteristics with parasites, such as their ability to evade the immune system and exploit the host for their own growth and survival.
In 2015, a study published in the journal Oncotarget reported the discovery of a parasitic microbe called Chlamydia in the blood of cancer patients. The researchers suggested that this microbe might play a role in the development of cancer, although more research is needed to confirm this.
In summary, while cancer is not a parasite in the traditional sense, there is some evidence to suggest that certain parasitic microbes may play a role in the development of cancer. Further research is needed to fully understand the relationship between cancer and parasites.