I have a 5 cm long 2 cm wide firm lump on volar forearm. Slightly closer to the wrist end and Slightly to the right mid forearm. This lump is only visible/palpable when I make a fist or flex. I can move it side to side by not up and down and it seems to be attached to my tendon because when I move it I can see my whole tendon all the way down to the wrist move. I have carpal tunnel like symptoms in that wrist but the lump is not tender. About 8 months ago I had horrible constant wrist pain that lasted for months but that went away and I noticed the lump shortly after. Orthapedic surgeon assessment was herniation with muscular extrusion of flexion or a mass of flexor tendon. My mri isn’t for another 2 weeks. From my understanding muscle hernias in forearm are rare, do you think it’s a tumor? Have you ever seen a tumor behave this way?