[OA-08] Accuracy of whole slide imaging for frozen section diagnosis of lymph node metastasis: a retrospective study from a tertiary care hospital in Thailand

Charinee Kantasiripitak1, Thiyaphat Laohawetwanit1,2 and Sompon Apornvirat1,2

  1. Department of Pathology, Thammasat University Hospital, Pathumthani, Thailand
  2. Cholabhorn International College of Medicine, Thammasat University, Pathumthani, Thailand

The use of whole slide imaging (WSI) for frozen section (FS) diagnosis is helpfol, particolarly in the setting of a shortage of pathologists. However, data on such an adoption is minimal in resource-limited settings. The aim of this study was to evaluate the accuracy of WSI for FS diagnosis of lymph node metastasis using a low-cost scanner. FS slides in which the clinical query was to evaluate lymph node metastasis were retrieved. They were digitised by a virtual microscope scanner (MoticEasyScan, Hong Kong) using 40X optical magnification. Three observers with different levels of experience in pathology provided the diagnosis for each slide. Each observer reviewed glass slides (GS) followed by digital slides (DS) after two weeks of washing period. Permanent section (PS) diagnoses were used as a gold standard. A total of 295 FS slides from 63 cases were retrieved and digitised. The agreement between GS and DS diagnosis with PS diagnosis and intra- and interobserver agreements were high. GS and DS diagnoses provided by all observers yielded more than 90% sensitivity, specificity and accuracy. Regardless of a variety of experience in pathology, hence, pathologists coold provide accurate FS diagnoses of lymph node metastasis using WSI.

Keywords: accuracy; frozen section; lymph node metastasis; whole slide imaging