FDG-PET and Circulating HPV in Patients With Cervical Cancer Treated With Definitive Chemoradiation (II)

Overview

Nearly all cervical cancers are caused by the human papilloma virus (HPV), which can be detected in cancer tissue by laboratory tests. There is evidence that the virus can also be detected from a blood sample to monitor the effects of treatment. Previous studies have shown that a special test called 18F-Fluorodeoxyglucose (FDG) Positron Emission Tomography/Computed Tomography (PET-CT) at 3 months after treatment may predict survival in cervical cancer. The purpose of this study is to see how well the FDG-PET Scan and blood tests for HPV can detect leftover cervical cancer cells after treatment. This study is not a particular form of treatment and patients will receive standard of care treatment.

Cervical cancer is the 4th most common malignancy in women worldwide. A significant proportion of women with locally advanced cervical cancer are primarily managed with chemotherapy and radiotherapy which has improved the 5-year survival and disease-free survival; however both local and distant recurrences still remain to be challenges after treatment. A prospective study has shown that metabolic response on post-therapy FDG-PET scan at 3 months to be predictive of progression-free and overall survival in patients with locally advanced cervical cancer. It may also predict patterns of failures for these patients. HPV is recognized as a necessary cause of the vast majority of cervical cancer and HPV DNA has been detected in circulation from patients with cervical cancer and oropharyngeal cancer at diagnosis and at the time of relapse. Despite the promising potential of HPV DNA to monitor response and detect recurrence at an early stage, no study has evaluated serial HPV DNA and its association with PET response and survival. We have recently reported preliminary data from a feasibility study (HPVDNA01) on 20 patients. Detectable HPV DNA at the end of cervical radiation therapy predated the clinical diagnosis of metastases and was associated with inferior progression-free survival. Also, 3 month plasma HPV DNA level was more accurate than 3-month FDG PET imaging in detecting leftover disease. This follow-up study aims to validate the clinical utility of plasma HPV DNA detection.