Up to one third of men will have a common condition causing a small, painless lump in the scrotum called a spermatocele. A spermatocele is a benign cyst in which there is an accumulation of sperm that comes from the head of the epididymis.  It may also be referred to as an epididymal cyst as it is found within the long, tightly coiled tube called the epididymis that lies above and behind each testicle.