Detection of HPV of types 16 and 18 by Digital PCR in samples of paraffin-embedded tumor tissue from patients with oropharyngeal squamous cell carcinoma

• Grant number: 18/23995-1
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: July 01, 2019
• End date: May 31, 2020
• Field of knowledge: Health Sciences - Medicine
• Principal Investigator: Ana Carolina de Carvalho Peters
• Grantee: Camila Marques Schiavetto
• Host Institution: Hospital do Câncer de Barretos. Fundação Pio XII (FP). Barretos , SP, Brazil

Abstract

Introduction: Head and Neck Squamous Cell Carcinomas (HNSCC) are tumors frequently associated with excessive consumption of alcohol and tobacco and, more recently, human papillomavirus (HPV) infections, especially in oropharyngeal tumors. HPV-positive tumors present a distinct clinical and epidemiological behavior, characterized by an increase in incidence, by affecting younger individuals and presenting a better prognosis. The accuracy of HPV detection in paraffin embedded samples is a challenge, thus, methodologies that enable detection of virus DNA accurately from a small amount of material would be useful in the clinical routine. Objectives: To standardize the detection of HPV types 16 and 18 (HPV-16 and HPV-18) by digital PCR in FFPE samples containing tumor material from biopsies or surgical pieces of patients with oropharyngeal SCC treated at Hospital de Cancer de Barretos and to evaluate the agreement with data obtained previously by the Immunohistochemistry (IHC) for p16. Materials and Methods: This study will evaluate the detection of HPV-16 and HPV-18 DNA by Digital PCR in 50 samples of oropharyngeal SCC. In order to evaluate the concordance between the digital PCR and IHC results for p16, we will determine the Cohen's kappa coefficient. To assess the potential for detection of HPV-16 and HPV-18 in the samples, sensitivity, specificity, accuracy, positive and negative predictive values and area under the ROC curve (AUC) will be calculated. Accuracy measurements will also be performed using the IHQ result for p16, in order to evaluate the use of the results of the two tests to better classify these patients.