The level of serum squamous cell carcinoma antigen 2 – an isoform of SCCA that is widely used as a tumor marker for SCC – was significantly higher in both skin and serum of patients with psoriasis, compared with healthy volunteers in a recent study, correlating with psoriasis severity score and reflecting treatment efficacy.
The intensity of skin and serum levels of SCCA2 was correlated in patients with psoriasis, and the study results also suggest that Th17 cytokines (IL-17 and IL-22) induce SCCA 2 elevation in serum and skin. “Significant elevation of SCCA2 is associated with disease severity and reflects treatment efficacy. SCCA2 may be a useful biomarker in psoriasis, reflecting Th17-type inflammation – the main determinant of the severity of psoriasis,” wrote Dr. Yuko Watanabe of Yokohama (Japan) City University and associates (Br J Derm. 2016 Jan 29. doi: 10.1111/bjd.14426).
According to the investigators, the commonly used psoriasis area severity index (PASI) is suboptimal because it is not truly quantitative and varies among clinicians. Since there are several new treatment options for psoriasis, including biologics, the authors believe that a new serum marker for psoriasis is needed to evaluate disease activity and manage treatment.
The prospective, cross-sectional study included 123 patients with psoriasis and 25 healthy controls. Serum SCCA2 levels were significantly higher in patients with psoriasis, compared with controls: a median of 2.7 ng/mL versus 0.70 ng/mL, respectively (P <.0001). Serum SCCA2 levels were positively correlated with PASI for all patients with psoriasis, regardless of subtype. In 38 patients on monotherapy or combination therapy with drugs to treat psoriasis, SCCA2 levels decreased in the 35 patients whose PASI improved on treatment (P <.0001) and increased in the three cases of clinical deterioration.
The study was supported by a grant from Japan’s Ministry of Education, Culture, Sports, Science and Technology. The investigators declared that they had no conflicts of interest.