The relationship between estrogen therapy and endometrial carcinoma is well known. The effect of estrogen replacement on other gynecologic malignancy is less clear. Estrogen receptors have been identified in all mullerian tissues. There are reports of partial responses of epithelial ovarian cancer to anti-estrogen medications suggesting that there may be a role for estrogen in the tumour growth.

The beneficial effects of estrogen replacement include vasomotor stability, prevention of vulvar and vaginal atrophy, and (epidemiologically the most important) a positive effect on the prevention of osteoporosis and a protective effect from vascular disease.

Progestogen therapy is much more controversial. Progestogens are known to protect the `at risk' endometrium from developing cancer. The effect of exogenous progestogen on breast cancer incidence has recently come into question. Certainly even a small increase in relative risk would be a major concern in a disease as common as breast cancer.

Still another reservation held about synthetic progestogens is their effect on serum lipids. These compounds tend to reverse the potential protective effects of estrogen by lowering the HDL and raising the LDL.

A policy of hormone replacement to reflect the above concerns is presented. Clearly this area is dynamic and our understanding of these hormones, their receptors and their relationship to both the development and the treatment of gynecologic tumours, is continually developing. This document attempts to use the current state of our knowledge to provide a rational policy for hormone replacement in gynecologic oncology patients.

For patients with potential estrogen sensitive tumours, hormone replacement should be directed towards symptom control and avoided for the general prophylaxis against ASHD, Osteoporosis etc.

When hormones are considered necessary, no waiting period is necessary.

Note: this represents the consensus opinion of the Gynecologic Oncology Group at the BC Cancer Agency. These recommendations have also been reviewed and accepted by the Breast Tumour Group.