Response Adapted Incorporation of Tislelizumab Into the Front-line Treatment of Older Patients With Hodgkin lYmphoma

The goal of this clinical trial is to test the effect of tislelizumab treatment in patients with Hodgkin lymphoma. The main question it aims to answer is whether including a drug called tislelizumab in first-line treatment of Hodgkin lymphoma for patients age 60 years and older is effective and well-tolerated. Participants will initially receive tislelizumab infusion every 21 days for 3 doses. After this a PET scan will be performed to assess the response. The subsequent treatment patients receive will depend on the following factors: 1. The lymphoma stage (early stage or advanced stage) 2. The presence or absence of specific high-risk features at the time of diagnosis 3. How well the lymphoma responds to the initial 3 doses of tislelizumab