A re-evaluation of squamous cell carcinoma antigen (SCC) as a serum marker for non-small cell lung cancer.

Squamous cell carcinoma antigen (SCC) is still a widely used tumor marker for monitoring non-small cell lung cancer (NSCLC), although recent reports discourage its routine use because of low sensitivity. This is a study evaluating the efficacy of SCC and CYFRA21-1 in diagnosing NSCLC. A chart review was performed in a university hospital in Japan, covering a period of 10 years, up to October 2004. During the study period, 142 (35.5%) among 400 NSCLC patients diagnosed, received serum assays of both SCC and CYFRA21-1. Elevated SCC and CYFRA21-1 levels were found in 29.6% and 59.2% of patients, respectively. SCC sensitivity was only 13.0% but CYFRA21-1 sensitivity rose to 73.9% in metastatic patients. The adjunct of SCC increased the CYFRA21-1 sensitivity by 6.3% in the overall population and by only 2.2% for patients with metastases. SCC determination should be considered an inefficient method as a potential diagnosing tool for NSCLC patients, and it provides no additional value when used in combination with CYFRA21-1.