Article Text
PDF
Abstract
Introduction/Background The 2020 WHO classification of gynaecological tumors has introduced as the main criteria for classification of vulvar squamous cell carcinomas (VSCC) their etiological relationship with human papillomavirus(HPV) infection, dividing VSCC into two categories: HPV-associated and HPV-independent VSCC. Additionally, recent evidence suggests that HPV-independent tumors should be further divided according to p53 mutational status. We aimed to evaluate the clinical and prognostic implications of these new criteria.
Methodology We retrospectively identified patients treated for VSCC in our hospital from 1985 to 2022 (n=196). Tumors were reviewed and classified in compliance with 2020 WHO criteria, according to p16 immunohistochemistry and HPV testing. HPV-independent tumors were subclassified as p53 wild-type and mutant. The clinical and pathological features of tumors were compared and disease free-survival (DFS) and disease-specific survival (DSS) were evaluated using univariate and multivariate analysis.
Recurrence-free survival and disease-free survival Kaplan-Meier curves
Results Thirty-six (18%) patients had HPV-associated and 160(82%) HPV-independent tumors, 88% of whom showed mutant p53. Patients with HPV-independent tumors were significantly older (76 vs 62 years,p<0.05) and had bigger tumors (29 vs 20 mm,p<0.05). HPV-independent tumors with mutant p53 were more deeply invasive than those with wild-type p53 (8 vs 5 mm,p<0.05). Mean follow-up was 53 months. HPV-independent tumors were associated with shorter DFS (recurrence rate 48% vs 17%, p<0.05), both in the univariate and multivariate analysis (Figure 1). A tendency to worse DSS was identified in patients with HPV-independent tumors, particularly in patients with p53 mutant tumors (mortality rate 15% for p53 mutant, 10% for p53 wild-type, and 5% for HPV-associated VSCC, p=0.2; Figure 1), despite the differences did not reach statistical significance.
Conclusion The 2020 WHO classification of VSCC has clinical and prognostic implications. Among patients with HPV-independent VSCC, patients with mutant p53 show specific clinical features. Different treatment of VSCC patients, according to HPV-association or not, should be considered in the future.