The Incidence of Vaginal Intraepithelial Neoplasia 2+ in Patients With Previous Hysterectomy Cervival Intraepithelial Neoplasia 3+ Between 2005–2015: A Population-Based Study

In light of the rarity of vaginal cancer, the role of vaginal vault testing following hysterectomy for preinvasive or early cervical cancers is unclear. The objective was to determine the subsequent risk of VaIN2/3, and invasive vaginal cancer following hysterectomy, and to potentially identify individuals at higher risk who may benefit from vaginal vault testing. The authors performed a population-based retrospective study using administrative databases to identify the study population. They identified patients who between 2005-2015 underwent hysterectomy after cervival intraepithelial neoplasia 3+ (CIN3+)/adenocarcinoma in situ (AIS) and calculated the rate of VAIN2 and invasive vaginal cancer. Exclusion criteria are as follows: <21 years and CIN3+ diagnosis prior to 2005. Patients were followed until 2021. During the study period, 6,230 patients underwent hysterectomy for a diagnosis of CIN3+/AIS. The subsequent rates of VaIN2/3, in situ, and invasive cancer were 1.9% (119/6,230) and 0.3 (18/6,230), respectively. Of these, most (84.7%) were made within 5 years of hysterectomy and remained stable over time (2.0% in 2005-2009, 2.4% in 2010-2015). However, only 54% of patients had vault cytology after hysterectomy; among these, 8.2% were abnormal of which 22.8% were diagnosed with VAIN2+. In addition, the risk of VaIN2+ was 5.8% when there was residual CIN3+ versus 2.1% when absent. Individuals with evidence of CIN3+/AIS at time of hysterectomy are at elevated risk of developing VAIN 2+, with the highest risk occurring within 5 years from surgery. Vault cytology within 1 year of surgery will identify most cases of VAIN2+, but further data monitoring and integration of HPV testing will be required to determine this screening strategy.