Aprox 3wks back of rhs hand=constant numbness with moderate pain. have a soft med size lump btwen thumb/index fingr closer 2wrist. past wk pain>tia

CTS / Ganglion cyst: Without more information (which fingers are most affected-exact location and texture of the lump) i'm giving you the most common cause. Irritation and swelling of the median nerve usually causes parasthesias in the thumb, index finger, middle finger and 1/2 the ring finger (depending on anatomic varients) ganglion cysts initially come and go with pressure leading to bulging of fluid.