Track: Clinical Studies

Abstract:

Eccrine porocarcinoma (EP) is a rare, aggressive adnexal neoplasm and due to its rarity, limited information is available regarding high-risk features. Using the National Cancer Database (NCDB), this study aims to characterize the prognostic utility of lymphovascular invasion (LVI) in EP. The NCDB was used to identify patients with EP from 2010 to 2021. Clinicopathologic variables were assessed, including age at diagnosis, disease stage, location of primary site, and LVI status. Kaplan-Meier analysis assessed overall survival, and Cox proportional hazards analysis evaluated for independent factors associated with overall survival. Multivariable logistic regression analysis was utilized to assess for independent predictors of advanced disease stage (nodal involvement/distant metastases) on initial presentation. 310 patients with EP were identified, of whom 49 (15.8%) had LVI+. On Kaplan-Meier analysis, the 5-year overall survival was worse for patients with LVI+ (42.1% vs 72.8%, p<0.0001). On Cox proportional hazards analysis, advanced disease stage (HR: 2.87, 95% CI: 1.66-4.98, p=0.0002) was associated with poorer overall survival, while LVI+ trended toward statistical significance (HR: 1.48, 95% CI: 0.87-2.50, p=0.14). On multivariable logistic regression, LVI+ status (OR: 17.3, 95% CI: 7.55-42.3 p<0.0001) and disease site on the head and neck compared to the extremities (OR: 3.00, 95% CI: 1.25-7.90, p=0.013) were associated with advanced disease stage. Patients with EP with LVI+ status had poorer overall survival on univariate analysis, and LVI+ status was independently associated with distant metastases. This analysis suggests that LVI demonstrates prognostic utility in risk stratifying patients with EP.