Evaluation of the one-step nucleic acid amplification assay for detecting lymph node metastasis in patients with cervical and endometrial cancer: A multicenter prospective study

Abstract

ObjectiveThis multicenter study aimed to evaluate the accuracy of the one-step nucleic acid amplification (OSNA) assay in diagnosing lymph node metastasis (LNM) in patients with cervical and endometrial cancers. MethodsSurgically removed LNs from patients with cervical and endometrial cancer were sectioned at 2-mm intervals along the short axis direction and alternately examined using the OSNA assay and conventional histopathological examination. Ultrastaging (200-μm LN sections) was performed for metastatic LNs using hematoxylin and eosin staining and immunostaining with an anti-CK19 antibody in cases where the OSNA assay and histopathological examination (performed using 2-mm LN sections) results showed discordance. ResultsA total of 437 LNs from 133 patients were included; 61 patients (14%) showed metastasis by histopathological examination, with a concordance rate of 0.979 (95% confidence interval [CI]: 0.961–0.991) with the OSNA assay. The sensitivity and specificity of the OSNA assay were 0.918 (95% CI: 0.819–0.973) and 0.989 (95% CI: 0.973–0.997), respectively. Discordance between the two methods was observed in nine LNs (2.1%), and allocation bias of metastatic foci was identified as the major cause of discordance. ConclusionsThe OSNA assay showed equally accurate detection of LN metastasis as the histopathological examination. We suggest that the OSNA assay may be a useful tool for the rapid intraoperative diagnosis of LN metastasis in patients with cervical and endometrial cancers.