A Registry for People With T-cell Lymphoma

Inclusion Criteria: * Written informed consent * Adequate fresh or archival tumor biopsy or intent to obtain fresh tumor biopsy. * Pathologically-confirmed mature T- or natural killer (NK)-cell lymphoma meeting one of the following diagnostic criterion (based on WHO classification and NCCN guidelines): * T-cell prolymphocytic leukemia * T-cell large granular lymphocytic leukemia * Chronic lymphoproliferative disorder of NK cells * Aggressive NK-cell leukemia * Systemic Epstein-Barr virus (EBV)-positive T-cell lymphoma of childhood * Chronic active EBV infection of T- and NK-cell type, systemic form * Hydroa vacciniforme-like lymphoproliferative disorder * Adult T-cell leukemia/lymphoma * Extranodal NK/T-cell lymphoma, nasal type * Enteropathy-associated T-cell lymphoma * Monomorphic epitheliotropic intestinal T-cell lymphoma * Intestinal T-cell lymphoma, not otherwise specified (NOS) * Indolent T-cell lymphoproliferative disorder of the gastrointestinal tract * Hepatosplenic T-cell lymphoma * Subcutaneous panniculitis-like T-cell lymphoma * Mycosis fungoides (limited to those with ≥ stage IB disease and those receiving active therapy) * Sézary syndrome * Primary cutaneous anaplastic large cell lymphoma (receiving systemic therapy) * Primary cutaneous Gamma-Delta T-cell lymphoma * Primary cutaneous CD8+ aggressive epidermotropic cytotoxic T-cell lymphoma * Primary cutaneous acral CD8+ T-cell lymphoma (receiving systemic therapy) * Peripheral T-cell lymphoma, not otherwise specified * Angioimmunoblastic T-cell lymphoma * Follicular T-cell lymphoma * Nodal peripheral T-cell lymphoma with TFH phenotype * Anaplastic large cell lymphoma, ALK-positive * Anaplastic large cell lymphoma, ALK-negative * Breast-implant associated anaplastic large cell lymphoma. * NOTE: Patients with diagnoses of mycosis fungoides, primary cutaneous anaplastic large cell lymphoma, and/or primary cutaneous acral CD8+ T-cell lymphoma must be receiving systemic therapy. Exclusion Criteria: * Patients with of mycosis fungoides, primary cutaneous anaplastic large cell lymphoma, and/or primary cutaneous acral CD8+ T-cell lymphoma not receiving systemic therapy. * Inability to collect prospective data, measure response, or perform adequate follow-up assessments in the clinical judgment of the treating physician. NOTE: Repository participation does not exclude participation in clinical trials, nor does existing clinical trial participation exclude enrollment in the study herein outlined.