Oestrogen therapy ’causes ovarian cancer to grow five times faster’

WASHINGTON - A new study has revealed that oestrogen therapy used by menopausal women causes a type of ovarian cancer to grow five times faster.

Researchers at the University of Colorado Cancer Center found that menopausal estrogen replacement therapy (ERT) also significantly increases the likelihood of the cancer metastasizing to the lymph nodes.

Monique Spillman and her team measured ovarian cancer growth in the abdomen of mice using novel techniques for visualizing the cancer.

In mice with ER+ ovarian cancer cells, which were tagged with a firefly-like fluorescent protein that allowed them to be tracked, the introduction of estrogen therapy made the tumors grow five times faster than in mice that did not receive the ERT.

“We were able to identify estrogen-regulated genes specific to ER+ ovarian cancer that are not shared with ER+ breast cancers. We believe these genes can be specifically targeted with new anti-estrogen therapies that could more effectively treat ER+ ovarian cancers,” Spillman said.

The study dealt only with estrogen replacement, which is linked to higher risks of ovarian cancer, not combined estrogen/progesterone therapy that is used with women who retain their uteruses. It did not test whether the estrogen replacement actually could cause the development of these cancer cells.

“We cannot make clinical recommendations based on what is happening in mice,” cautioned Spillman.

“Every woman is different and needs to talk to her doctor about the decision to use hormone replacement therapy.”

The study was released online Oct. 19, 2010. Cancer Research. (ANI)