Risk Factors Affecting Clinical Outcomes of Low-risk Early-stage Human Papillomavirus-Associated Endocervical Adenocarcinoma Treated by Surgery Alone: Application of Silva Pattern

This study aimed to report the clinical outcomes and risk factors for survival of patients with low-risk early-stage human papillomavirus-associated (HPVA) endocervical adenocarcinoma (EAC) treated with surgery alone. This retrospective study obtained the clinicopathological data of patients with early-stage HPVA EAC who underwent surgery between 2012 and 2018. The Silva pattern of invasion was determined by reviewing pathology slides. Locoregional recurrence-free survival (RFS), RFS, and overall survival were calculated, and the risk factors for survival were analyzed. One hundred seventeen patients with a median follow-up of 5.2 years (0.5-9.7 yr) were included. The most common histologic type was usual (94/117, 80.3%). The Silva pattern was A in 79 patients (67.5%), B in 30 (25.6%), and C in 8 (6.8%). The 5-year locoregional RFS, RFS, and overall survival rates were 92.4%, 87.8%, and 97.2%, respectively. The presence of intermediate-risk factors and Silva pattern C were significantly associated with worse survival. Based on these findings, patients were categorized into 2 groups: Group 1 (Silva pattern A or Silva pattern B without intermediate-risk factors) and Group 2 (Silva pattern B with intermediate-risk factors or Silva pattern C). Group 2 showed significantly worse outcomes than Group 1, including the 5-year locoregional RFS (98.6% vs 68.0%), RFS (96.4% vs 54.6%), and overall survival (100.0% vs 86.5%). In conclusion, surgery alone for early-stage HPVA EAC resulted in favorable outcomes. Consideration of the Silva pattern, in addition to well-known risk factors, could help in precise risk group stratification of low-risk, early-stage HPVA EAC.