Cross-gender massage means a female is working on a male and vise Versa. Surely, having a regulation doesn't mean that it is adhered to privately. But in massage parlors held in casinos, this is the rule they adhere to.

That was back in the 90-s though when I lived in Vegas. I don't know what do they do nowadays when a person can change gender by a flick of his/her/their finger. )))