Horizontal tumor extent (HZTE) has limited prognostic significance in 2018 FIGO stage I endocervical adenocarcinoma (ECA): a retrospective study of 416 cases

Purpose: The 2018 International Federation of Gynecology and Obstetrics (FIGO) update on cervical cancer staging eliminated horizontal tumor extent (HZTE) as a staging parameter in stage IA (microscopic) disease. We aimed to determine whether HZTE correlates with outcomes in early stage ECAs and FIGO should reinstate HZTE as a staging parameter in futures updates. Methods: We retrospectively analyzed 416 FIGO 2009 stage I ECAs from 17 institutions and re-assigned stage using FIGO 2018. Correlation between HZTE, overall (OS) and recurrence free survival (RFS) was performed using univariable and multivariable analyses. Results: Re-staging 416 cases resulted in 126 (30.3%) IA and 290 (69.7%) IB cases; 85 (67.5%) IA tumors had HZTE ≤ 7 mm, while 41 (32.5%) were > 7 mm; 32 (11%) IB tumors had HZTE ≤ 7 mm, while 258 (89%) were > 7 mm (p = 0.0001). Four (3.2%) IA (1 IA1, 3 IA2) patients developed recurrence (3 ≤ 7 mm, 1 > 7 mm) compared to 41 (14.1%) IB patients (p = 0.002). Fourteen IB and no IA patients died of disease (8 IB1, 1 ≤ 7 mm). Cox univariate analysis demonstrated that only RFS is significantly influenced by HZTE (p = 0.01), while OS and RFS were not influenced by HZTE on multivariate analysis. Conclusion: HZTE has limited prognostic value in early stage ECAs and is only associated with RFS on univariate but not multivariate analysis. HZTE does not improve prognostication of patients with stage I ECAs as per 2018 FIGO staging. Consequently, the rationale to remove this variable from FIGO staging is justified for ECAs.