Relationship between trait anxiety, brain activity and natural killer cellactivity in cancer patients: A preliminary pet study

The purpose of this study is to examine the relationship between psychologi cal factors, regional brain activity and natural killer cell activity (NTKA ). Eight patients with malignant diseases were studied by FDG-PET under a r esting condition. NKA and degree of anxiety and depression were measured us ing Taylor's manifest anxiety scale (MAS) and Zung's self-rating depression scale (SDS). Linear correlation of NKA and psychological measures to the r egional brain metabolism in cancer patients was examined using statistical parametric mapping (SPM). Positive linear correlation between NKA and regional metabolic rate ratios was identified in the visual association cortex, anterior cingulate gyrus ( CG) and sensorimotor area, and negative correlation was identified in the i nferolateral prefrontal cortex (ILPFC), prefrontal cortex (PFC), orbitofron tal cortex (OFC) and anterior temporal cortex. Positive linear correlation to the MAS score was identified in the visual association cortex, anterior CG, primary sensorimotor area and the posterior parietal cortex, and negati ve correlation was detected in the ILPFC, PFC, OFC and anterior temporal co rtex. The NKA and MAS scores positively correlated with each other (p < 0.0 01). The result might serve as supporting data for a hypothesis that psycho-immu ne interaction is also mediated by the cerebral cortex and limbic system. C opyright (C) 2001 John Wiley & Sons, Ltd.