ALTERATIONS OF PHOSPHATIDYLCHOLINE CONCENTRATIONS IN THE SERUM OF PATIENTS WITH MAMMARY-CANCER

As determined by reversed-phase liquid-solid extraction, concentration of total phosphatidylcholines in the serum of 53 patients with mammar y cancer was significantly (P<0.003) increased to 2.24+/-0.59 mg/ml wh en compared with the normal value of 1.86+/-0.36 mg/ml. In 31 fraction s of their individual molecular species separated by high-performance liquid chromatography there was a shift to compounds composed of longe r fatty acids that were significantly more abundant than in normal ser um. The concentration of fractions containing stearic, oleic, linoleic , eicosatrienoic, arachidonic and docosahexaenoic acid as well as trac es of C17 acids was 2-5 fold enhanced. On the other hand, molecular sp ecies containing palmitic acid combined with palmitoleic, oleic linole ic, arachidonic and further polyunsaturated fatty acids are considerab ly decreased in cancer serum. All these atypical phosphatidylcholines are apparently specific products of tumor cells and are released into the blood stream. The possibility of using these alterations of phosph olipid metabolism for the follow-up of cancer patients is further inve stigated.