A Fibromyxoid Stromal Response Is Associated With an Infiltrative Tumor Morphology, Perineural Invasion, and Lymph Node Metastasis in Squamous Cell Carcinoma of the Vulva

Patterns of invasion and stromal response are understudied in vulvar squamous cell carcinoma. The aim of this study was to explore whether histologic features such as an infiltrative pattern of invasion and fibromyxoid stromal response (FMX-SR) are meaningful prognostic factors. We reviewed 143 vulvar squamous cell carcinoma resections and correlated patterns of invasion and stromal response with patient age, ethnicity, depth of invasion, tumor size, perineural invasion (S100/AE1/3 stain), lymph node involvement (LNI), extranodal extension, margin status, pathologic stage, and recurrence. Univariate analyses of continuous variables were performed using t tests, whereas Pearson χ tests were used for categorical variables. Logistic regression analyses examined the relationship between histopathologic characteristics and clinical outcomes. There was a statistically significant association between infiltrative tumors and an FMX-SR in comparison with noninfiltrative tumors (P