Tumor specific protein 70 targeted tumor cell isolation technology can improve the accuracy of cytopathological examination.

Abstract

Objectives: Although existing cytopathological examination is considered essential for the diagnosis of malignant serous effusions, its accuracy is pretty low. Tumor specific protein 70 (SP70), which is highly expressed on human tumor cell membrane, was identified in our previous study. This study aimed to explore whether SP70 targeted tumor cell isolation technology with immunomagnetic beads can improve the accuracy of cytopathological examination.

Methods: Cytopathological analysis with SP70 targeted tumor cell isolation technology was used in this study. In total, 255 cases were enrolled. Serous effusions were analyzed by both existing cytopathological examination and the new cytopathological analysis concurrently.

Results: The sensitivities of existing cytopathological examination and the new cytopathological analysis were 51.26 % and 85.43 %, respectively, while the specificities were 100 % for both. This new cytopathological analysis demonstrated a higher interobserver agreement with malignant diagnosis than the existing cytopathological examination (kappa coefficient: 0.720 vs. 0.316, p<0.001). In addition, it achieved superior diagnostic efficacy for malignancy differentiation compared to existing cytopathological examination (AUC: 0.927 vs. 0.756, p<0.001). The follow-up results showed that 74 malignant cases with final clinical diagnosis were positive only with the new cytopathological analysis. Among these cases, there were 58 negative and 16 atypical by the existing cytopathological examination. In these malignant cases, 74.3 % (55/74) had been confirmed to have serosa metastasis based on radiographic evidence, and 73.7 % (28/38) harbored tumor hotspot mutations.

Conclusions: As illustrated in this work, cytopathological analysis with SP70 targeted tumor cell isolation technology can improve the accuracy of existing cytopathological examination prominently.