Suggest Cause And Remedy For Tumor On The Upper Thighs

I have a mass or tumor on the inside upper thigh of both legs. One is around the size of a baseball and has been steadily growing for around 6 months. The other is just starting and is growing...it has been there for around 1- 1 and a half months. Any ideas what they could be? The larger one has become painful within the past couple of months.