A Question of Etiquette

I have a quandary that occurred last week at the gym.

What is the correct way to respond to seeing an elderly gentleman naked and spotting that his gonads are frankly wrong?

I’m no medical doctor but I do possess a pair myself and with the internet you’re probably never more than two clicks away from plummage even if you don’t want to see it. However even my amateur knowledge are advanced enough to know that each one should be roughly the size of a baby’s head. Once I’d clapped eyes on these monsters my mind started racing, had nobody ever told him they weren’t natural, had his wife never seen another pair before and assumed they all looked like that, had the man never ejaculated in his life before, should I suggest he see a doctor, had he seen me staring, could he even sit down or cross his legs, had he read Buster Gonad, did he have a wheelbarrow, how on earth did he run at the gym?

What is the correct polite response? I just got changed and walked away still none the wiser and I’m scared to google to find out just in case it comes with images.