Trends in the Incidence of Vulvar and Vaginal Cancers With Different Histology by Race, Age, and Region in the United States (2001-2018)

Objectives: The race, age, and region-stratified incidence of vulvar (VUC) and vaginal (VAC) cancers with different histology were unclear.Methods: Data was retrieved from the United States Cancer Statistics database. Average annual percent change (AAPC) and incidence rate ratio (IRR) were calculated.Results: Overall, VUC incidence increased from 18.3 (per 1,000,000 woman-years) to 19.6, but VAC incidence decreased from 5.6 to 4.4. VUC squamous cell carcinoma (SCC) incidence increased (AAPC, 0.96; 95% CI, 0.66-1.25), VUC adenocarcinoma (ADE) incidence stabilized (AAPC, -0.24; 95% CI, -1.44 to 0.98), and VUC other malignancies (OM) incidence decreased (AAPC, -1.31; 95% CI, -2.58 to -0.02). While VAC incidence decreased for any histology (AAPC, -0.63; 95% CI, -1.03 to -0.22; AAPC, -1.60; 95% CI, -2.80 to -0.39; and AAPC, -1.57; 95% CI, -2.24 to -0.89 for SCC, ADE, and OM). Similar trends were observed in most of the stratifications.Conclusion: VUC and VAC incidences varied by histology overall and within stratifications by race, age, and region. The incidence decreased for VUC and VAC with all histologies, except for the increasing VUC SCC incidence.