Calculating power for a matched case-control study nested within a cohort

[John7]

I would like to look at the association between circulating melatonin and risk of endometrial cancer for a matched case-control study nested within a prospective cohort. With having samples for 500 cases of endometrial cancer and 500 controls, I wonder what would be my power to observe an odds ratio of 1.8. I appreciate if you show me how to do this in SAS.

Thanks so much!