Evaluation of tumor budding and poorly defined clusters as histological biomarkers in squamous cell carcinomas of the vulva

Abstract

Several histopathological risk factors have been examined in vulvar cancer (VC) so far. However, the prognostic relevance of morphological biomarkers such as tumor budding (TB) and poorly defined clusters (PDCs) remains to be determined. Material and Methods: We histologically analyzed the formation of peritumoral and intratumoral TB and PDCs in a cohort of 157 patients with VC. We assessed their association with clinico-pathological features and evaluated their prognostic impact in terms of the risk of local recurrence and occurrence of metastasis (Fisher’s exact test) as well as overall survival (Log-rank test). Results: We determined a distinct prognostic relevance of peritumoral TB with regard to occurrence of metastasis (Fisher’s exact test; p = 0.0415) as well as a significant reduced risk local recurrence in the group with absent intratumoral TB (Fisher’s exact test; p = 0.0004). Furthermore, we showed that patients without peritumoral budding formation had a significant superior prognosis in terms of overall survival (p = 0.0366, x2 = 4.370). Conclusions: This study shows that several new histomorphological biomarkers may serve useful in predicting the clinical course of patients with VC, identifying patients at a lower risk of developing metastases/local recurrence as well as improved overall survival.