Joint detection of multiple HPV-testing technologies and evaluation of clinicopathological characteristics discriminate between HPV-independent and low-copy HPV-associated cervical squamous cell carcinoma (CSCC) -an analysis of 3869 cases.

OBJECTIVES: This study aimed to investigate the frequency and clinicopathological characteristics of HPV-independent cervical squamous cell carcinoma (CSCC). METHODS: A total of 3869 patients with CSCC from 2017 to 2021 were searched. p16INK4a immunochemistry (IHC), two HPV-DNA(L1) polymerase chain reactions and HPV mRNA in situ hybridization were performed. Viral copies were detected using the 21 HPV quantitative test. RESULTS: Six cases showed negative results in all four assays (group 1, 0.16%). Twenty-seven cases showed discordant results (group 2), and 3836 cases presented all-positive results (group 3). p16INK4a IHC showed similar sensitivity, specificity, and positive predictive value compared to the other three direct HPV assays. 21 HPV genotyping showed 100% of negative predictive value. HPV copies were extremely lower in Group 2 than in Group 3 (P < 0.01), but were not significantly different from those in Group 1. Older age, advanced FIGO stage (III-IV) and abnormal p53 (p53abn) IHC were independent predictors of HPV-negative status in univariate and multivariate logistic regression. Group 2 had similar proportions of age >60 years and p53abn IHC with Group 1, but had fewer cases with advanced FIGO stage (P < 0.05) and TILs (P < 0.05). Groups 1 and 2 had worse disease-free survival (DFS) and disease-specific survival (DSS) than Group 3 (P < 0.01), while no significant difference was found between these two groups. HPV-negative status was a risk factor for both DFS (P < 0.05) and DSS (P < 0.01) in univariate but not multivariate Cox regression. CONCLUSIONS: Joint detection of multiple technologies and evaluation of clinicopathological characteristics discriminate between HPV-independent and low-copy HPV-associated CSCC cases that present similar prognoses. Additional attention should be paid to these low-copy HPV-associated cases in clinical practice.