Based on 10× genomics scRNA‐seq data of two LUAD‐LM patients from the GEO database (LUAD‐LM‐A, GSM4555887; and LUAD‐LM‐D, GSM4555890), we further confirmed the high levels of CEACAM6 expression in CSF‐CTCs compared to various CSF immune cells (Figure 1C). Here, CEACAM6 is linked to lymphangioma.