Based on the univariate Cox regression analysis, predictive factors for mortality among CM patients were as follows: TP levels in the CSF were higher than the patients’ age (HR 2.47, 95% CI, 1.26.4.82, P = .008), receiving the best supportive care after the diagnosis of CM (HR 6.12, 95% CI: 2.61–14.3, P < .001), and being EGFR mutation-negative (HR 3.63, 95% CI: 1.49–8.89, P = .005) (Table 3). The gene discussed is EGFR; the disease is cutaneous mastocytosis.