The cortical morphology of cingulate cortex and microarchitecture of cingulum bundle correlate with cancer pain and anxiety in lung cancer patients.

The cingulate cortex (CC) and cingulum bundle (CB) are key structures involved in pain processing. Thus, we explored the correlations between cortical morphometry of the CC, white matter integrity of the CB, and pain-related assessments in lung cancer patients with cancer pain (CP+). Structural and diffusion spectrum imaging, along with emotion and pain-related assessments, were collected from 45 CP+ patients, 47 lung cancer patients without pain (CP-), and 35 healthy controls (HC). Cortical morphometry and tract-based automatic analysis evaluated the CC and CB. One-way ANOVA revealed significant group differences in sulcal depth (SD) within the CC, as well as in fractional anisotropy (FA) and radial diffusivity (RD) within the CB. Post-hoc tests indicated that the CP+ group had greater SD than the CP- group, and smaller FA as well as greater RD than both the CP - and HC groups. In the CP+ group, RD of the CB was positively correlated with SD of the CC, and the anxiety score was positively correlated with RD of the CB and SD of the CC. In the HC group, the anxiety score was negatively correlated with SD of the CC. This study revealed distinct patterns of structural alterations across the three groups. Differences in both CB and CC structures were observed in CP+ relative to CP - and HC groups, were interrelated, and were associated with anxiety. These findings highlight the significant contribution of CC and CB in cancer pain processing, while also serving as potential biomarkers for negative emotion.