Abstract:

Objective

To compare one-step nucleic acid amplification （OSNA） technique and the frozen section （FS） method in intraoperative detection of sentinel lymph node （SLN） metastasis in breast cancer patients， and evaluate the diagnostic performance of OSNA.

Methods

A prospective study was conducted on clinical data of 116 patients with primary breast cancer admitted to the General Hospital of the Northern Theater Command from November 2021 to April 2023. Each patient underwent sentinel lymph node biopsy， and 287 identified SLNs were subjected to both OSNA and FS testing. Postoperative pathological examination served as the gold standard for diagnosis. Diagnostic concordance rates， sensitivity， specificity，positive predictive value （PPV） and negative predictive value （NPV） were calculated for both OSNA and FS.Kappa test was used to assess the consistency of OSNA and FS with the postoperative pathological result （gold standard）. McNemar’s test was employed to compare the sensitivity and specificity of OSNA and FS，as well as the serial and parallel combinations of the two methods. Receiver operating characteristic （ROC） curves were plotted， and the area under the curve （AUC） was calculated to compare the diagnostic efficacy of different methods. Chi-squared tests and Mann-Whitney U tests clinicopathological features between lymph node metastasis group and non-metastasis group.

Results

Vascular invasion and total tumor burden were associated with SLN metastasis （χ2 =16.454，P＜0.001；Z=-8.876，P＜0.001）. For the 116 patients， the diagnostic concordance rate of OSNA with postoperative pathology was 93.1% （108/116）， with a sensitivity of 95.8%（23/24）， specificity of 92.4% （85/92）， PPV of 76.7% （23/30）， and NPV of 98.8% （85/86）. The kappa value was 0.808 （P＜0.001） and the AUC was 0.941 （95%CI： 0.885-0.997， P＜0.001）. The sensitivity of OSNA and FS showed no statistically significant difference （95.8% vs 87.5%，χ²=0.500，P=0.500）. For the 287 SLNs， the diagnostic concordance rate of OSNA was 94.8% （272/287）， with a sensitivity of 93.8% （30/32）， specificity of 94.9% （242/255）， PPV of 69.8% （30/43）， and NPV of 99.2% （242/244）. The kappa value was 0.771 （P ＜0.001） and the AUC was 0.961 （95%CI： 0.911-1.000， P＜0.001）. The sensitivity showed no significant difference between OSNA and FS （93.8% vs 90.6%， χ2 = 0.333，P= 1.000）. The sensitivity of OSNA combined with FS in series of the 116 patients was 87.5% （21/24）， specificity 92.4%（85/92）， PPV 75%（21/28）， and NPV 96.6%（85/88）. The sensitivity indicated a significant difference compared with OSNA alone （χ² = 7.111，P= 0.004）. For the parallel combination of OSNA and FS， the sensitivity was 95.8% （23/24）， specificity 92.4% （85/92）， PPV 76.7% （23/30）， and NPV 98.8% （85/86）. The detection rate of positive case was the same as that of OSNA alone， indicating no statistical significance.

Conclusion

OSNA is a reliable method for detecting SLN metastasis in breast cancer patients.

Key words: Breast neoplasms, One-step nucleic acid amplification, Sentinel lymph node, Metastasis