CEACAM5 and retinitis pigmentosa 1: Zuo et al. [17] found that serum CA153 levels were elevated in patients with anti-MDA5+DM secondary RP-ILD, which is also an independent risk factor for ASS-ILD in secondary RP-ILD; elevated serum CEA and CA125 levels are also independent risk factors for ASS-ILD secondary to RP-ILD [18].