What Causes Tingling Sensation On Right Thigh?

I have an area of skin on my right thigh which has a constant tingling sensation. It sometimes feels numb and is sensitive to touch.

I have no obvious skin changes although it feels as though there is bruising.

This has been going on for about 3 months. It started off feeling as though i had a small lump about the size of my thumb nail. It has now spread to an area about the size of my hand.

Can you offer any insight as to what this may be and is it something I should be concerned about?