Squamous cell carcinoma antigen as a novel candidate marker for amniotic fluid embolism

We aimed to evaluate the clinical usefulness of serum squamous cell carcinoma (SCC) antigen for the diagnosis of amniotic fluid embolism (AFE).

Sera and information of 20 patients with AFE (autopsy-proven AFE, four cases; clinical AFE, 16 cases) were obtained from the Japan Amniotic Fluid Embolism Registration Center at Hamamatsu University School of Medicine. As controls, we included 74 gestational-age-matched healthy women who gave birth to healthy newborns during the period from December 2012 to January 2014. Receiver-operator curves (ROC) were used to evaluate the diagnostic performance of SCC levels for prediction of AFE.

Serum SCC antigen levels in women with autopsy-proven AFE (112.0 ± 169.4 ng/mL, P = 0.001) and clinical AFE (9.5 ± 10.3 ng/mL, P = 0.004) were significantly higher than those in healthy controls with normal delivery (4.4 ± 2.2 ng/mL). On ROC analysis, the optimal cut-off value for SCC antigen levels was 7.15 ng/mL, for which the sensitivity and specificity for AFE prediction was 60.0% and 89.2%, respectively (area under the ROC, 0.785; 95% confidence interval, 0.663-0.908; P < 0.001).

Serum SCC antigen may be a promising predictor of the entry of amniotic fluid into the maternal circulation, potentially serving as a candidate marker for noninvasive diagnosis of AFE.