To explore serum biomarkers quantitatively in association with disease severity and treatment response in psoriasis patients. Methods: Fifteen psoriasis patients were treated with adalimumab. At different visits before and after treatment, quantitative body surface area (qBSA) was obtained from standardized digital body images of the patients, and psoriasis area severity index (PASI) was also monitored. Serum squamous cell carcinoma antigen (SCCA) and tumor necrosis factor-alpha (TNF-α) were detected by using Microparticle Enzyme Immuno Assay and Enzyme Linked Immunosorbent Assay. The serum biomarkers were also tested in healthy volunteers as normal control. Receiver operating characteristic (ROC) curve analysis was used to explore the optimal cut-off point of SCCA to differentiate mild and moderate-tosevere psoriasis. Results: The serum SCCA level in psoriasis group was significantly higher (P < 0.05) than in the normal control group. After treatment, the serum SCCA levels were significantly decreased (P < 0.05). SCCA level was well correlated to PASI and qBSA. In ROC analysis, when taking PASI=10 or qBSA=10 as the threshold, an optimal cut-off point of SCCA was found at 2.0ng/mL with the highest Youden’s Index. Conclusion: Serum SCCA might be a useful quantitative biomarker for psoriasis disease severity. The study was funded by national natural Science foundation of china (No 81201238, 81472898).

Serum squamous cell carcinoma antigen in psoriasis: a potential quantitative biomarker for disease severity