Soluble cd28 levels during immunotherapy

Methods of diagnosing and predicting cancer recurrence are provided comprising measuring soluble CD28 levels in a subject wherein an increase in soluble CD28 is indicative of cancer recurrence or an impending cancer recurrence. Also provided are methods of determining a response to a PD-1/PD-L1-based immunotherapy in a subject in need thereof, comprising measuring sCD28 levels at at least two points in time in a subject receiving a PD-1/PD-L1-based immunotherapy, where a decrease indicates a response and an increase indicates a lack of a response. 提供了诊断和预测癌症复发的方法，包括测量受试者中的可溶性CD28水平，其中可溶性CD28的增加指示癌症复发或即将发生癌症复发。还提供了确定有需要的受试者中对基于PD-1/PD-L1的免疫疗法的应答的方法，包括在至少两个时间点测量接受基于PD-1/PD-L1的免疫疗法的受试者中的sCD28水平，其中降低表明应答和增加表明缺乏应答。