Medicus April 2016

C L I N I C A L E D G E

HORMONE REPLACEMENT THERAPY POST GYNAECOLOGICAL CANCER

Dr Stuart Salfinger Sub-Specialist Gynaecologic Oncologist Dr Pippa Robertson O&G Registrar King Edward Memorial Hospital

G ynaecological cancer accounts for 9.4 per cent of new cancers in women in Australia with treatment often resulting in an iatrogenic menopause from loss of ovarian function. Previously it has been thought that prescribing Hormone Replacement Therapy (HRT) could theoretically cause recurrence of residual disease or trigger new hormone dependent disease, which has raised safety concerns regarding its use. This, combined with limited studies, has resulted in confusion and apprehension when seeking to prescribe HRT to a woman experiencing a decreased quality of life from premature menopause whilst also dealing with the physical and psychological impacts of a cancer diagnosis. This is most relevant to younger women undergoing treatment for gynaecological cancers, in particular those who have been treated for borderline ovarian tumours, non-epithelial ovarian carcinoma and cervical carcinoma where surgery and/or radiation can render them menopausal. In fact, only few gynaecological cancers appear to be an absolute contraindication to HRT and prescribing it can help to minimise debilitating symptoms and maintain a higher quality of life, which is a vital part of cancer care. It can be more challenging (and controversial) in young women having risk reduction surgery where they may be rendered menopausal by this treatment and also carry a risk of breast cancer. Endometrial Carcinoma Endometrial cancer accounts for 44.5 per cent of gynaecological cancers and 9.4 per cent of all cancer in females in the Australian population. Thirty-seven per cent of cases occur in those under the age of 60 with a survival rate of 86-91 per cent in this group.

diagnosed, 20-25 per cent had not yet experienced menopause; 75 per cent of these cancers are stage 1 when diagnosed. Current treatment is based on staging but usually involves a total hysterectomy and bilateral salpingo-oophorectomy and in some cases, pelvic and para-aortic lymph node dissection. For those pre-menopausal women, this results in early sudden onset menopause, which is often severe. As 90 per cent of cases are estrogen dependent and risk factors for endometrial cancer include unopposed estrogen therapy and obesity (thought to be from a progesterone deficiency resulting from anovulation and conversion of androgens to estrogens in peripheral adipose tissue), one would assume that HRT is contraindicated in these women. However, this theory has been debunked in several clinical trials. In a prospective trial by Ahyan et al, 50 patients with Stage 1 and 2 endometrial cancer, matched with controls, were commenced on HRT four to eight weeks post operatively. This showed no recurrence in the HRT group and one recurrence in the control group. Another study by Suriano et al looked at 249 patients with stage 1, 2 and 3 endometrial cancer. Of these, 75 patients who were commenced on estrogen replacement therapy within six months of starting surgery were well matched against patients who had not commenced treatment. This showed a 14 per cent recurrence in those not on therapy and 1 per cent in those who were. A large randomised double blinded prospective trial of estrogen HRT vs placebo in stage 1 or 2 endometrial cancer was undertaken in 1997-2003 by Barakat et al. Initially no adverse outcome was found from HRT. However, the study was hampered by the publication of the Women’s Health Initiative in 2002, which led to a significant drop-out of patients. Subsequently the trial was ceased, as the accrual numbers were unable to be achieved. However, this and

Endometrial cancer is the most common and, of those

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