Hard, 1cm round lump under skin front upper thigh unchanged for 7 years. is it cancer? female age 35.

Probably not!: A 1cm lump that has not changed for 7 years is very unlikely to be cancer! Why? Because cancer grows, especially if it is not treated. What you describe sounds like a benign mass or cyst. An ultrasound and/or biopsy would give you a diagnosis, but it might not be necessary. Ask your primary care provider to take a look at this next time you're in. And read about lipomas to see if that fits!