Existence of a squamous cell carcinoma antigen-immunoglobulin complex causes a deviation between squamous cell carcinoma antigen concentrations determined using two different immunoassays: first report of squamous cell carcinoma antigen coupling with immunoglobulin A

Prospective Analysis of Squamous Cell Carcinoma Antigen-1 and -2 for Diagnosing Sinonasal Inverted Papilloma

Background: The goal of this research was to confirm whether preoperative serum squamous cell carcinoma antigen (SCCA)-1 and -2 levels are useful diagnostic markers for sinonasal inverted papilloma (IP) in a prospective study. Methods: Participants were 102 patients who underwent consecutive endoscopic sinus surgery: 18 with IP, two with other types of papilloma, 77 with chronic rhinosinusitis, four with sinonasal cancer, and one with hemangioma. SCCA-1 and SCCA-2 were measured preoperatively by an automatic chemiluminescence immunoassay and an enzyme-linked immunosorbent assay, respectively. Results: SCCA-1 and SCCA-2 values were significantly correlated (r = 0.603, p < 0.001). Receiver operating characteristic analysis for differentiating papilloma (IP and other types of papilloma) from other diseases yielded an area under the curve of 0.860, with a Youden index of 1.75. Combined with SCCA-2 analysis, the detection system had a sensitivity and specificity of 0.65 and 0.98, respectively. While our study did not find a strong link between SCCA levels and skin or lung diseases, smoking status may influence SCCA levels in IP patients (p = 0.035). We recommend a cutoff value of 1.8 ng/mL for SCCA-1 in IP diagnosis. Conclusions: SCCA-1 and SCCA-2 when combined with imaging and pathology hold promise for enhancing the preoperative detection of IP, which would be a valuable contribution to clinical practice.

Impact of anti-squamous cell carcinoma antigen antibodies on serum squamous cell carcinoma antigen levels measured by chemiluminescent immunoassay and chemiluminescent enzyme immunoassay

OBJECTIVE

The serum squamous cell carcinoma antigen (SCCA) level is a well-known tumor marker for squamous cell carcinoma. In this study, we examined the impact of immunoglobulin (Ig)-bound macromolecular SCCA on serum SCCA levels measured by 2 different methods.

METHODS

Seventy-five serum samples with an SCCA level >5.0 ng/mL as determined by a chemiluminescent immunoassay (CLIA) were also analyzed using a chemiluminescent enzyme immunoassay (CLEIA). The levels of IgG- and IgA-type anti-SCCA antibodies, which form immunoglobulins and macromolecules, respectively, were determined using an enzyme-linked immunosorbent assay. An absorption test was performed to confirm the presence of anti-SCCA antibodies.

RESULTS

The correlation coefficient between the values measured by CLEIA and CLIA was 0.768. The ratio of SCCA levels measured by CLEIA to those measured by CLIA in 14 samples with IgG-type anti-SCCA antibodies was significantly lower than that in samples without these antibodies (P < .031). Absorption tests showed that SCCA levels measured by CLIA might be falsely high in samples with IgG-type anti-SCCA antibodies, probably due to reactions with SCCA1.

CONCLUSION

The level of SCCA as measured by CLIA and CLEIA methods correlate well, but the presence of SCCA antibodies can affect the results of the CLIA method.

Squamous Cell Carcinoma Antigen: Clinical Application and Research Status

The squamous cell carcinoma antigen (SCCA) is a tumor marker that has gained increasing attention for its biological functions and significance in normal physiological and pathological processes. Not only SCCA but also circulating immune complexes of SCCA and immunoglobulin M (IgM) are involved in normal physiological and pathological processes, providing a background for numerous clinical studies aimed at assessing the potential role of SCCA, SCCA–IgM, and SCCA isoform complexes in clinical practice. Previous studies support the clinical value of SCCA as a tumor marker for either diagnosing squamous cancers or monitoring the response to radiotherapy or chemotherapy, tumor relapse, and treatment failure. However, these studies show contrasting results, making the diagnostic or prognostic value of SCCA controversial. To reduce clinical heterogeneity across studies and achieve a more accurate and reliable comparison of results, a standardized detection method, scoring system, and cutoff level need to be established. Moreover, despite the fact that performances of different methods are comparable, the dynamic observation of tumor marker kinetics should be conducted under the same method.