*3.1. Patients' Characteristics*

Characteristics of 27 patients with newly diagnosed NF-PitNETs are summarized in Table 1. The patients were categorized into a CS (+) group (*n* = 17) and a CS (−) group (*n* = 10) (Figure 1, Table 1). The average age of patients with NF-PitNETs exhibiting CS invasion was higher than in those without CS invasion (*p* = 0.0030). There was no significant difference in terms of sex in both groups (*p* = 0.45). Tumor volume was significantly higher in the CS (+) group than in the CS (−) group (*p* = 0.0011). However, some NF-PitNETs easily invade into the CS despite their small tumor

size. There were no significant differences between the two groups in cystic formation (*p* = 0.78) and hemorrhagic component (*p* = 0.89).


**Table 1.** Patient characteristics and results.

CS: cavernous sinus, IHC: immunohistochemistry, VEGF: vascular endothelial growth factor, VEGFR: vascular endothelial growth factor receptor.
