Most if not all melanoma patients have low Vitamin D which means their bodies were dysfunctional in deeper ways which led to the cancer. The following is from a researcher: 
“…Then you have melanoma

Very deadly. Not caused by sunlight exposure. If you believe otherwise, you need to read up on the literature 

Cancer, including skin cancer, is fundamentally rooted in broken apoptosis (programmed cell death) and autophagy function, which is inextricably tied to circadian biology

And here’s what few people touch on

What do people who receive a skin cancer diagnosis also do for the entire duration of their lives?

• Live under toxic artificial light 24/7 = broken apoptosis and autophagy = begging for cancer

• Disrupt their circadian rhythm, which is CAUSATIVE of many cancers in the literature 

• Stare at an artificially blue lit device, especially at night while in bed

• Wear sunglasses

• Get a lot of direct sunlight through glass windows, which creates the skin cancer causing combination of UV-A and blue light together in isolation because of how glass manipulates the full light spectrum 

• Avoid the sun (chronically deficient D3 and broken melatonin cycles), next to not red and infrared light, etc

• Lack of melanin because they avoid the sun or artificially manipulate its full spectrum

• Melanin dysfunction for all of the above reasons, including a high non-native EMF environment which destroys the mitochondria by disrupting the voltage gated channels required for mitochondrial function

• High nnEMF abuse with the inverse square law working against them (think phone to head, lap on laptop, Airpods in ears, which amplifies the damage on melanin, the mitochondria, opsins, etc”

https://pubmed.ncbi.nlm.nih.gov/29657326/