Many proteins have been investigated as diagnostic or prognostic CSF parameters in LM patients during the last 30 years, including carcinoembryonic antigen (CEA; Klee et al, 1986), lactate dehydrogenase (LDH; Seidenfeld and Marton 1979; Van Zanten et al, 1986), beta-glucuronidase and beta-microglobulin (Ongerboer de Visser et al, 1985), a combination of tissue polypeptide antigen and CK-BB (Bach et al, 1993), fibronectin (Weller et al, 1990), and the epithelial HMFG-1 antigen (Moseley et al, 1989). This evidence concerns the gene CEACAM5 and lymphangioma.