A study of electron spin resonance spectra of whole blood from normal and tumour bearing patients.

Electron spin resonance spectra have been obtained from samples of frozen whole blood or separated blood cells and plasma. Blood samples were obtained from human controls having no diagnosed malignancy and from patients with a variety of benign and malignant tumours.The characteristic spectrum from control blood shows two main lines with g values of 4·2 and 2·049. Several smaller lines can also be observed. The line at g = 2·049 may be due to the copper protein ceruloplasmin. Although no qualitative differences could be found between the spectra from controls and cancer patients, samples from patients with certain types of tumour showed a significant increase in size of the g = 2·049 signal above control values. This was most noticeably the case with Hodgkin's disease and to a lesser extent with cancers of the breast. Squamous cell carcinomata, taken as a group, did not show an elevation in average size of the g = 2·049 signal. In this latter group, however, there were some indications that the effects of chemotherapeutic treatment could be followed during the early stages of such treatment. Examples are given in which onset of treatment with various cytotoxic agents was associated with reduction in size of the g = 2·049 signal.