This study is testing a medicine called atezolizumab for patients with a specific type of throat cancer related to human papillomavirus (HPV). Atezolizumab is a type of immunotherapy, which means it helps your immune system fight cancer. In this study, patients will receive atezolizumab through a vein (intravenously or IV) and will have CT (computed tomography) scans and MRI (magnetic resonance imaging) to monitor their progress. Some may also have a biopsy, where a small piece of the tumor is taken for testing.

• Study Duration: Patients will be followed for 2 years to check long-term effects.
• Participation Requirements: Participants must be at least 18 years old, not pregnant, and use birth control. They must also have a confirmed HPV-related throat cancer.
• Risks and Monitoring: Regular scans and possible biopsies will be done to monitor safety and effectiveness.

It's important for participants to understand the study's requirements and the commitment involved, such as regular hospital visits for treatment and scans. The study aims to see if this treatment is safe and effective in stopping the cancer from growing or spreading.