Erythrocyte stearic to oleic acid ratio in patients with ocular melanoma.

The main characteristics of malignant cells include increased metabolism and capacity for division which are associated with high membrane fluidity. Membrane fluidity is in turn controlled by multiple factors which include the ratio of saturated to unsaturated fatty acids in the cell wall i.e. the Saturation Index (SI). The SI is known to be reduced in neoplastic cells as well as in the circulating erythrocytes of patients with some malignant tumours but not others. It has been suggested that the SI may be useful as a marker of malignancy.