Menopausal hormone therapy carries increased cutaneous melanoma risk

The use of unopposed oestrogen in menopausal women may contribute to a heightened risk of cutaneous melanoma, a study has found.

Researchers used data from the Australian Longitudinal Study on Women's Health and followed 18,850 postmenopausal women for a median of 13.2 years. They retrieved information on menopausal hormone therapy prescriptions from the Australian Pharmaceutical Benefits Scheme, while data on clinically diagnosed cases of invasive and in situ cutaneous melanoma were drawn from the Cancer Registry and hospital data. 

During the follow-up, a total of 301 invasive and 55 in situ cases of cutaneous melanoma occurred. In the middle-aged cohort, 6,400 women never used hormone therapy during the follow-up, 3,668 used oestrogen therapy, and 157 used oestrogen combined with a progestogen. The corresponding numbers in the older cohort were 5,974, 2,327, and 48.

Multivariable Cox proportional hazards models showed that the use of oestrogen therapy conferred a 26-percent increased risk of cutaneous melanoma (hazard ratio [HR], 1.26, 95 percent confidence interval [CI], 0.98–1.61) and 16-percent greater risk of invasive disease (HR, 1.16, 95 percent CI, 0.88–1.52).

There was no association detected between exposure to oestrogen–progestogen combination and the risk of cutaneous melanoma (HR, 0.99, 95 percent CI, 0.37–2.67).

Additional studies are needed to establish the potential impact of different types of hormone therapy on cutaneous melanoma risk.