Systemic alterations in phospholipid concentrations of blood plasma in patients with thyroid carcinoma: an in-vitro P-31 high-resolution NMR study

In this study in-vitro P-31 high-resolution NMR spectroscopy of human blood plasma was optimized to obtain absolute concentrations of the major plasma phospholipids: phosphatidylethanolamine plus sphingomyelin /PE+ SM), 1- and 2-acyl-lysophosphatidylcholine (LPC1 and LPC2), phosphatidylinositol (PI) and phosphatidylcholine (PC). Plasma spectra of 33 patients with thyroid ca rcinoma were acquired at 121.49 MHz using a 300 MHz spectrometer. The patie nts were rendered hypothyroid (TSH >30 mU/l) in preparation for a whole-bod y scintigraphy. The whore-body scintigraphy showed tumour tissue or metasta ses in 16 patients (group C). Owing to an inconclusive whole-body scintigra phy, 17 patients were classified as being in remission (group B). After lev othyroxine substitution 14 patients of group B were measured in euthyroidis m too (group D). Besides these sub-groups, there was a control group made u p of 23 healthy volunteers (group A). Group B showed significantly higher P E + SM and PC concentrations than group C (0.59 +/- 0.02 mmol/l PE + SM in B vs 0.48 +/- 0.02 mmol/l in C; 2.1 +/- 0.1 mmol/l PC in B vs 1.6 +/- 0.1 m mol/l in C). In comparison with group D higher concentrations of the phosph olipids PE + SM and PC as well as PI were found in group B (0.59 +/- 0.02 m mol/l PE + SM in B vs 0.48 +/- 0.03 mmol/l in D; 0.074 +/- 0.005 mmol/l PI in B vs 0.046 +/- 0.004 mmol/l in D; 2.1 +/- 0.1 mmol/l PC in B vs 1.6 +/- 0.1 mmol/l in D). The data indicate that under the condition of hypothyroid ism only patients in remission (group B) show significantly increased phosp holipid concentrations, whereas the values in patients with remaining tumou r tissue (group C) do not differ from those of the reference groups A and D . This finding is interpreted as an interference between the hormonal statu s and the systemic effects of cancer. Copyright (C) 2000 John Wiley & Sons, Ltd.