The suspected link seems to be a negative one. This paper I found concludes: Discussion Our systematic review highlights the dearth of available evidence rega

The suspected link seems to be a negative one. This paper I found concludes: Discussion Our systematic review highlights the dearth of available evidence regarding the risk of skin cancers in relation to dietary omega-3 PUFAs. For SCCs, the combined results of the two informative articles 34,37 showed a nonsignificant 14% reduction among those with relatively high consumption of n-3 PUFAs. Only one article has addressed the association of fatty fish and melanoma, and it suggested a significant halving of risk in those with diets rich in oily fish. 35 Meta-analysis of the two studies with data available for BCC showed no association between n-3 PUFAs or oily fish and BCC. 36,38 https://pubmed.ncbi.nlm.nih.gov/24265065/ https://pubmed.ncbi.nlm.nih.gov/24265065/