Abstract 5417: Recurrence-free survival in patients with early-stage HPV-associated adenocarcinoma of the cervix stratified by Silva patterns.

Abstract Background: HPV-associated adenocarcinoma of the cervix presents challenges in adjuvant treatment compared to squamous cell carcinoma of the cervix. Silva Pattern-based classification has emerged as a histomorphologic predictor supplementing the traditional Sedlis Criteria established in GOG 92. While not part of FIGO staging, it is considered in clinical guidelines, as the Silva Pattern C confers a higher risk of nodal metastasis and disease recurrence; however, its prognostic role in early-stage disease and in patients who do not meet Sedlis criteria remains less defined. We aimed to determine whether Recurrence-free survival (RFS) in patients with early-stage HPV-associated adenocarcinoma of the cervix differs between patients with Silva Pattern C and those with A/B. We hypothesize that Silva Pattern C can guide adjuvant management in patients with negative Sedlis Criteria. Methods: We conducted a retrospective study of patients with surgically treated FIGO Stage IA-IB2 HPV-associated adenocarcinoma of the cervix. Cases were identified through our institutional pathology database under an IRB-approved protocol (2015 to 2025). Pathology specimens from cone biopsies and hysterectomies were reviewed by gynecologic pathologists. Silva patterns were assigned accordingly. Clinical data were obtained from electronic medical records. The study outcome was to determine the RFS, measured from diagnosis to recurrence or to the last follow-up. A Kaplan-Meier analysis was used to compare Silva patterns A/B vs. pattern C. Results: Our sample consisted of 13 patients with HPV-associated adenocarcinoma of the cervix. We identified 6 patients with Silva Patterns A/B and 7 with Silva Pattern C. Three recurrences occurred exclusively in the Silva Pattern C group. RFS was 42.9% in Silva C and 100% in Silva A/B (log-rank p-value: 0.4142). Median follow-up was 29 months (6-108 months) for Silva Pattern C and 15 months (0-46 months) for Silva Pattern A/B. All recurrences occurred in patients with FIGO stage IA2-IB1 disease who did not meet Sedlis Criteria for adjuvant radiation. Times to recurrence were 10, 24, and 90 months. Conclusions: Patients with Silva Pattern C experienced worse RFS. None of the patients with Silva Pattern C who recurred met Sedlis criteria for adjuvant radiation. Sedlis criteria mainly guide squamous cell carcinoma management; only 12% of GOG 92 patients had adenocarcinoma, limiting its use for this group. Our findings suggest that the Silva pattern C may provide clinically actionable prognostic information and can help guide multidisciplinary discussions regarding adjuvant management. Prospective validation of clinical algorithms incorporating Silva pattern-based classification in larger cohorts is warranted. Citation Format: Ana Lucia Rosario Santos, Hisham Bahmad, Jovanka Ravix, Andre Pinto, Navya Nair, . Recurrence-free survival in patients with early-stage HPV-associated adenocarcinoma of the cervix stratified by Silva patterns abstract. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 1 (Regular Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(7 Suppl):Abstract nr 5417.