Application of 2011 International Federation for Cervical Pathology and Colposcopy Terminology on the Detection of Vaginal Intraepithelial Neoplasia

PURPOSE: To evaluate the colposcopic accuracy of the detection of vaginal intraepithelial neoplasia (VaIN) according to the colposcopic terminology for the vagina from the 2011 International Federation of Cervical Pathology and Colposcopy (IFCPC). METHODS: A total of 467 women who were suspected of having VaIN and underwent colposcopy at Obstetrics and Gynecology Hospital of Fudan University from January to December 2018 were included in this retrospective cohort study. The 2011 IFCPC revised terminology for the vagina was applied, and the agreement between colposcopic diagnosis and vaginal biopsy pathology was analysed. RESULTS: Agreement between colposcopy and pathology was 69.16% (kappa=0.437, p<0.001), with 23.34% overestimated and 7.49% underestimated diagnosis for colposcopy. The agreement was the lowest (35.71%) in the high-grade VaIN group, which was significantly different from that of other lesion grade groups (p<0.01). Among grade 1 findings, thin acetowhite epithelium was the most frequent (80.51%). Grade 2 findings and vascular patterns were rare. The positive predictive values of the micropapillary pattern were 55.98% for low-grade VaIN and 5.98% for high-grade VaIN. The specificity of iodine negativity was 10.92% for low-grade VaIN and 8.30% for high-grade VaIN. There were significant differences in the maximum size of single lesions and in the number of lesions among different grade lesion groups. CONCLUSION: The agreement between colposcopy findings utilizing the 2011 IFCPC terminology and vaginal pathology is moderate, and more definite findings for high-grade VaIN may be needed. The micropapillary pattern can be considered an alternative low-grade finding, while iodine staining is nonspecific for all lesions. Scattered and spotty lesions suggest low-grade VaIN, while large single lesions suggest high-grade VaIN.