Got no links or science to prove this ... all I have is intuition and my experience.
Kinda think skin cancer may be linked to some chemical exposure, more likely to sun exposure, and to good old heredity, i.e. your complexion. I'm a very white White Boy ... Irish - German dna, and I can get skin cancer from just going out to the mailbox once a day. Wife is Italian-American, is outdoors some but not a lot, and has never had skin cancer. Her sister otoh spent a lot of time tanning outdoors and in tanning beds when she was younger. Pretty sure she is cancer-free nowadays, but her skin is leathery, parchment looking. What she had spent a lot of time doing to look more attractive has had the opposite effect.
Dermatologist has me routinely scheduled for 2 x year visits, and most years I find something else and request 1 or 2 other appointments. History of Basal and Squamous ... no Melanoma so far ... AND four "Mohs Procedures." That latter has to not only be done by a Dermatologist, BUT by a Dermatologist who is specially certified to do Mohs. The Basals and Squamous are removed and sent off to Pathology; sometimes only by a skin scraping and no more post-op care than a band-aid, sometimes by a scalpel and a suture or two, which requires some relative inactivity so you don't pop the stitch before things heal.
Here's the thing ............ if you stay ahead of this, most skin cancers begin as "pre-cancers," sorta like you might be told after a colonoscopy. For colonoscopy virgins, it is not unlikely the doctor will find and snip some polyps, which are sent to Pathology. If they are found to be cancerous, more work is in store. Many are, however, found to be benign, and you're routinely only scheduled for another colonoscopy 3-5 yrs later ... you're "good to go."
Skin cancers, and pre-cancers, tend to be flatter, and, thank-you-very-much, are right there to be seen, without a hose up your ass. I tend to get them on my face, and they begin as dry, scaly patches that are easier to feel than to see. With my usual appointments, the doctor can tell at a glance if they are "pre - " or more worrisome. The stuff he doesn't think are worth excision + Pathological review are just "burned" off by a frozen Nitrogen spray then+there. Minor, temporary, irritation+reddening, disappears soon.
He also prescribes (5% Flurorouracil Cream) I can use at home to intercept pre-cancers and minimize my need for doctor visits. Shit is effective IF you stay on top of things ... my Doc usually gets annoyed when he sees I wasn't attentive enough between visits, but the fault is more with me, not the ointment. Similar to the Nitrogen ... minor irritation+reddening ... quick to subside.
Now, here's the maybe(?) bad thing. I have only heard this once, yrs ago, at a previous doctor's office, and it was in idle conversation from his Nurse, not him. If sun or other uv light decides to trigger skin cancer on you, it can happen in other parts of you than where the exposure was. Seems(?) to be true in my case. Out with the dogs most of the year, wearing tee shirt + gym shorts. Some pre-cancers on my exposed forearms, but that's it. my Doc will spray them if at all. My real history is up on the face, even though I wear a wide brim hat. Single biggest one I ever had, one that required some digging and multiple sutures was on my upper chest but below the neckline of my tees. Not sure if that Nurse was right or not, but my history does not contradict her ... something to think about