To investigate the changes and significance of serum cysteinyl aspartate specific proteinase-4 (Caspase-4) in patients with non-small cell lung cancer (NSCLC) after microwave ablation.

One hundred and fifty-nine patients with NSCLC admitted to our hospital and Provincial Cancer Hospital from March 2013 to January 2016 were selected as the subjects of study. All patients received microwave ablation. Serum Caspase-4 levels were measured by active fluorescence method in patients with NSCLC before and after radiofrequency ablation. Serum Caspase-4 levels in NSCLC patients with different prognosis were compared. The prognostic value of serum Caspase-4 in patients with NSCLC was analyzed by ROC curve. The mean survival time of NSCLC patients with different serum Caspase-4 levels was compared. Cox single factor and multi-factor analysis were used to analyze the related factors affecting the prognosis of patients with NSCLC.

The serum Caspase-4 level of NSCLC patients after microwave ablation was significantly lower than that before operation, and the difference was statistically significant [(3.51±0.82) ng/ml vs. (4.33±0.96) ng/ml, P<0.05]. The serum Caspase-4 level of NSCLC patients in death group was significantly higher than that in survival group, and the difference was statistically significant [(5.01±0.63) ng/ml vs. (3.04±0.47) ng/ml, P<0.05]. The AUC, sensitivity and specificity of serum Caspase-4 in evaluating the prognosis of NSCLC patients after microwave ablation were 0.851, 65.79% and 90.91%, respectively. The average survival time of NSCLC patients with Caspase-4≥3.17 ng/ml was significantly lower than that of NSCLC patients with Caspase-4<3.17 ng/ml, and the difference was statistically significant [30.19 (95%CI: 27.84~32.49) months vs. 33.19 (95%CI: 31.77~34.60) months, P<0.05]. Cox univariate analysis showed that age, pathological type, degree of differentiation, TNM stage, lymph node metastasis, Caspase-4 levels might be related to the prognosis of NSCLC (P<0.05). Further Cox multivariate regression analysis showed that the TNM stages, lymph node metastasis and Caspase-4 were closely related to the prognosis of NSCLC patients (P<0.05).

The serum Caspase-4 level was significantly decreased in NSCLC patients after microwave ablation. The serum Caspase-4 level was closely related to the prognosis of NSCLC patients. Detecting the serum Caspase-4 level after microwave ablation has important clinical significance for evaluating the prognosis of NSCLC patients.