Lumpy Mass on testicle

I discovered a lumpy mass on my testicle the other day. (It has appeared in the last month.)  It is about 1/3 the size of my right testicle, on the bottom of the testicle.  

It doesn't hurt, but is tender if I try and squeeze it.  It is attached to the testicle inside the scrotum - not separate or outside.  

I have had a vasectomy.  Is this something I need to worry about?  What could it be?

[Ash Tewari, MD, M.Ch.]

Hi skeptical1,

A mass on the testicle can be either from the testis itself or it may be from one the appendages of the testis. Ususlly a testicular mass itself is not tender. This sounds more likely to be an appendicular mass and may have arisen from the epididymis which can occur sometimes after a vasectomy. However a physical examination, testicular sonography and blood tests for tumor markers are essential to rule out cancer. It is advisable for you to get yourself examined by a urologist at the earliest.

AT

[skeptical1]

Much appreciate your time.  I will be making an appt asap.