PT  - JOURNAL ARTICLE
AU  - Powell, Aime
AU  - Hodgson, Anjelica
AU  - Cohen, Paul A
AU  - Rabban, Joseph
AU  - Park, Kay
AU  - Glenn Mccluggage, W
AU  - Blake Gilks, C
AU  - ,
AU  - Singh, Naveena
AU  - Oliva, Esther
TI  - PR049/#741  Improved risk prediction in HPV-associated endocervical adenocarcinoma through assessment of binary silva pattern-based classification: international multicenter retrospective study of the international society of gynecological pathologists
AID  - 10.1136/ijgc-2023-IGCS.90
DP  - 2023 Nov 01
TA  - International Journal of Gynecologic Cancer
PG  - A57--A59
VI  - 33
IP  - Suppl 4
4099  - http://ijgc.bmj.com/content/33/Suppl_4/A57.2.short
4100  - http://ijgc.bmj.com/content/33/Suppl_4/A57.2.full
SO  - Int J Gynecol Cancer2023 Nov 01; 33
AB  - Introduction Endocervical adenocarcinomas (EACs) are neoplasms associated with diverse pathogenesis, morphology, and clinical behavior. The Silva pattern-based classification categorizes HPV-associated EACs based on the morphology of the invasion and predicts lymph node metastasis and recurrence. Traditionally the Silva classification was a three-tier system (pattern A, B, and C). A two-tier/binary system has recently been proposed whereby tumors are classified into low risk (pattern A/pattern B without lymphovascular invasion (LVSI)) and high risk (pattern B with LVSI/pattern C). Our aim was to develop a prognostic model for surgically treated FIGO stage IA2-IB3 EACs that incorporates patient age, LVSI, FIGO stage and three- and two-tier Silva systems.Methods The International Society of Gynecological Pathologists (ISGyP) established a multicenter consortium to pool de-identified individual patient data for patients with HPV-associated EACs. All participating pathologists completed mandatory online training.Results Our cohort comprised 792 HPV-associated EACs (table 1). On multivariate analysis a binary Silva system was associated with recurrence-free and disease specific survival (p<0.05) while FIGO 2018 stage I substages were not. In the current three-tiered system, disease specific survival for patients with pattern B tumors did not significantly differ from those with pattern C tumors while those with pattern A tumors did (table 2).Conclusion/Implications These findings highlight the need for future prospective studies to further investigate the prognostic significance of stage I HPV-associated EAC substaging and the inclusion of the binary Silva pattern of invasion classification, which includes LVSI status, as a component of treatment recommendations.View this table:Abstract PR049/#741 Table 1 Characteristics of the study cohort (n = 792). stratified by pattern of invasion/Silva patternView this table:Abstract PR049/#741 Table 2 Multivariate (adjusted) competing risk model investigating factors (including the pattern of invasion/Silva pattern as a binary classification system) associated with disease recurrence and disease specific survival for the cohort (n = 792)