In testicular cancer, how often is there not a palpable mass on the testicle and the cancer is inside the testicle.difference between on and in common?

Not meaningful diff.: This may be a semantic distinction more than a biological one. The cancer arises within the testicle, but may extend to the surface of that organ and bulge away from its surface. Thus, the tumor may FEEL to be on the testicle even though it has arisen from within it. Not all testicular cancer extends to the surface of the testicle. Palpation is clearly inferior to ultrasound examination here.