Halczy-Kowalik L, et al. - Given that poor oxygenation and nutrient scarcity favors the growth of squamous cell carcinoma of the oral cavity mucosa and that tumor growth is accompanied by reprogramming of lipid biosynthesis, researchers sought to report on the quantitative or qualitative relationship of the fatty acids (FAs) content in squamous cell carcinoma (SCC) of the oral mucosa, in the adjacent tumor microenvironment (ATME) and in the blood serum. All thirty patients with squamous cell carcinoma grade 1–3 had 8 of 25 identified fatty acids. The tumor had the highest percentages of C16:0 and C18:1n9, tumor adjacent tissue had highest percentages of C18:1n9 and C16:0, and blood serum had the highest percentages of C16:0 and C18:0. Independent of the tumor grade, tumor adjacent tissues showed higher frequencies and amounts of C22:1n13, C22:4n6, C22:5n3 and C24:1 than blood serum. As per findings, oral cavity SCC adjacent to the tumor microenvironment and blood serum of the patients show intensive lipid changes. Although, tumor grade influenced the number and magnitude of associations between particular FAs in all three environments, ie, tumor, ATME and serum, the dependency of FAs percentage from tumor grade was the most noticeable in ATME.