CEACAM5 and esophageal squamous cell carcinoma: Similarly, Table 3 demonstrates that YKL-40 improved the sensitivity (70.21%) significantly in detecting early-stage ESCC compared with the individual tumor markers (CEA: 10.64%; CYFRA21-1: 40.43%; SCCA: 29.79%), and the combination of YKL-40 and SCCA was superior to the other combinations in the efficiency of diagnosing ESCC.