Proton nuclear magnetic resonance spectroscopy of plasma from healthy subjects and patients with cancer

Abstract

To evaluate the ability of proton nuclear magnetic resonance (NMR) spectroscopy to indicate the presence or absence of malignant disease, we analyzed plasma samples from 104 patients with untreated cancer of various types and from 164 healthy controls. All specimens were coded with random numbers, and the investigators were blind to patient category. A statistically significant difference (P less than 0.001) was found between the mean (+/- SD) line widths in the plasma samples from the controls (39.1 +/- 6.7 Hz) and the line widths in plasma from the patients with cancer (35.2 +/- 6.4 Hz). However, the values showed considerable overlap between the two groups. The average line widths in the 54 male (36.0 +/- 7.9 Hz) and the 110 female (40.5 +/- 5.6 Hz) controls were significantly different (P less than 0.001). Differences in the average line width were also found between 34 male controls 40 years old or older (33.9 +/- 6.5 Hz) and 20 younger men (39.6 +/- 8.8 Hz) (P = 0.008) and between 61 female controls 40 or older (38.8 +/- 5.7 Hz) and 49 younger women (42.5 +/- 4.7 Hz) (P less than 0.001). The average line widths in 36 women with cancer (35.5 +/- 6.8 Hz) and their controls matched for age and sex (39.0 +/- 6.3 Hz) were significantly different (P = 0.03) but again showed much overlap. In 29 men with cancer, the line widths were not different from those of controls matched for age and sex. We conclude that proton NMR spectroscopy is not generally reliable for the detection of cancer. Furthermore, our data demonstrate the importance of studying control groups matched for age and sex.