Are some people more prone to getting varicocele?

Lacking venous valve: Boys or men who lack venous valves in the spermatic vein or veins between testicle and left renal vein are more prone to developing a varicocele. They are only discovered at approaching puberty or later by presence of a scrotal swelling that feels like a bag of worms when subject is standing up or as part of an infertility workup.

No, ....: There has been no known acquired factors to make men prone to develop varicocele, and it's a disorder of congenital venous valve defects of spermatic veins. Don't worry.