Is there such a thing as urethral cancer, and if so, how do you avoid getting it?

Yes, but rare: Urethral cancer is rare and etiology is not well defined and it is not practical to suggest specific steps to avoid urethral cancer. However, avoiding smoking, excess alcohol, chemical dyes would reduce the risk of cancer in general.

There is such a: Thing as "urethral cancer" - the urethra being the tube that connects the bladder to the world, and it is shorter in women than in men. All of us would choose to avoid getting this, but I am aware only of constant irritation, such as a catheter, trauma, or repeated infections as associations. People with spinal cord injuries and neurogenic bladders at risk here perhaps. No known preventitive.