The growing and urgent need for interventions to mitigate cancer-related stigma in sub-Saharan Africa.

CID and GAD affect a substantial proportion of the global population. Epidemiological studies indicate that the lifetime prevalence of CID in adults is approximately 10% (), whereas that of GAD reaches up to 14% (). Despite their high prevalence, accurate diagnosis in clinical practice remains challenging. This is largely due to the lack of objective diagnostic biomarkers (). This challenge is further compounded by the frequent comorbidity of CID and GAD (). In routine clinical settings, patients are often treated with both hypnotics and anxiolytics (). However, CID and GAD are fundamentally distinct disorders with different underlying pathophysiological mechanisms. CID is primarily associated with dysregulation of sleep-related neural systems, involving regions such as the thalamus, hypothalamus, and hippocampus (). In contrast, GAD is mainly characterized by dysfunction in emotional regulation networks, particularly involving the prefrontal cortex, amygdala, and insula (). In cases of comorbidity, abnormalities may coexist in both sleep and emotional regulation systems. These differences suggest that CID, GAD, and their comorbidity may exhibit distinct neuroanatomical features. These features could be useful for differential diagnosis. Our previous study reported preliminary findings of patients with CID comorbid GAD (). However, that study was limited by a relatively simple design, as it did not include independent CID and GAD groups for comparison. To date, relatively few studies have systematically investigated the neuroanatomical features of comorbidity. Most existing research has focused on CID or GAD separately. Prior studies have identified neuroanatomical abnormalities in the prefrontal cortex, thalamus, and hippocampus in patients with CID (). Similarly, neuroanatomical alterations in the amygdala, prefrontal cortex, and insula have been reported in patients with GAD (). Among available neuroanatomical techniques, magnetic resonance imaging (MRI)-based measurement of gray matter offers several advantages. It is a rapid and routinely used examination, and gray matter morphology remains relatively stable over extended periods. Therefore, MRI-based gray matter measurement may represent a promising tool for improving the objective diagnosis of CID, GAD, and their comorbidity. In this study, we aimed to identify neuroanatomical features of CID, GAD, and CID comorbid GAD. We also explored their potential utility in disease classification. Compared with previous studies, our study has several strengths. Firstly, we included four well-defined groups: CID, GAD, CID comorbid GAD, and healthy controls. Secondly, we evaluated multiple gray matter metrics, including fractal dimension (FD), gyrification index (GI), and regional gray matter volume proportion. These metrics are objective and relatively robust to individual variability. In summary, we hope that neuroanatomical features can aid diagnosis in clinical practice. This may enable accurate identification of CID, GAD, and CID comorbid GAD in the future.