Radiation Therapy Plus Durvalumab for Tumor-Stage Cutaneous T-Cell Lymphoma

Inclusion Criteria: * Voluntarily provide written IRB-approved consent * Age ≥ 18 years * Histologically proven CTCL * Stage IIB-IV CTCL with ≥2 cutaneous tumors assessable for response * At least one cutaneous tumor amenable to radiation therapy. Must have at least 1 tumor assessable for response that will not undergo radiation. * Adequate organ function * Prior treatment is allowed if at least 4 weeks have elapsed since last chemotherapy and/or radiation and the subject has recovered from all treatment related toxicity Exclusion Criteria: * Prior allogeneic stem cell transplant. * Prior treatment with a PD-1/PD-L1 inhibitor * Active or prior documented autoimmune or inflammatory disorders within the past 3 years prior to the start of treatment. * Current or prior use of immunosuppressive medication within 14 days prior to first dose of durvalumab. * Known human immunodeficiency virus (HIV), hepatitis C virus (HCV) or active hepatitis B virus (HBV) infection. * History of hypersensitivity to durvalumab or any excipient * Receipt of live attenuated vaccination within 30 days prior the first dose of durvalumab. * Female subjects who are pregnant, breast-feeding or female patients of reproductive potential who are not employing an effective method of birth control * Male subjects who are not employing an effective method of birth control * Uncontrolled current medical illness, including, but not limited to ongoing or active infections, symptomatic congestive heart failure, unstable angina pectoris,unstable cardiac arrhythmia and/or psychiatric illness or other condition that in the opinion of the investigator would limit compliance with study requirements.