An international team of oncologists has suggested that a common form of prostate cancer treatment may actually increase the subsequent risk of colon cancer.

Called androgen deprivation therapy (ADT), the treatment consists of reducing the body’s levels of testosterone. Scientists studied the effect of two forms of ADT – gonadotropin-releasing hormone agonist (GnRH) injections and orchiectomy, or removal of the testes.

Researchers found that among men over the age of 67, both types of ADT raised the risk of colorectal cancer.

The team said that this likelihood was not especially high – about 1 percent for men who have undergone orchiectomy – but that the slightly increased risk should make physicians think twice before choosing therapies.

GnRH agonists and orchiectomy also cause hot flashes and osteoporosis, according to the University of Pittsburgh Cancer Institute.

The study’s authors concluded that ADT should only be used when there is enough evidence to suggest that it will be lifesaving.

More than 217,000 American men are diagnosed with prostate cancer each year, according to the American Cancer Society.