This protocol describes the pivotal accuracy study for the IdentiClone Dx TRG Assay. The intent of the accuracy study is to demonstrate agreement between the results of the IC TRG Dx Assay and a predicate devise or assay on retrospective and residual de-identified DNA extracted from FFPE (Formalin Fixed Paraffin Embedded) samples from individuals with suspected T-Cell Lymphoproliferations. The predicate device will be the LymphoTrack Dx TRG (FR1/FR2/FR3) Assays - MiSeq (LT Dx TRG-CE-IVD), which is a CE-IVD assay with a similar intended use as the IC TRG Assay on the same sample type.

Inclusion Criteria:

1. De-identified, residual FFPE specimens with a minimum of 8 curls

2. Subject Age ≥ 18

3. For suspected clonal positive specimens, FFPE specimens of subjects diagnosed (at the time the specimen was drawn) with T-cell Lymphoproliferative disease with at least one of the following:

   1. ICD10 Codes: C84, C85.8, C85.9, C86.1, C86.2, C86.3, C86.5, 86.6, C91.5, C91.6, C91.0, C91.z, C91.9, C94, C95, C96, or other T-cell lymphoma diagnosis
   2. b. T-cell lymphoproliferative disease diagnosis per collection site procedure (e.g., SNOMED)
   3. Mycosis fungoides or Sézary syndrome sample are acceptable

4. For suspected clonal negative specimens, FFPE specimens of subjects suspected of T-cell lymphoproliferative disease but diagnosed negative for T-cell lymphoproliferative disease. Up to 20% of the negative specimens may be from normal tissue or tissue diagnosed with diseases other than T-cell lymphoproliferative disease

Exclusion Criteria:

1.FFPE specimens that were fixed using formalin substitute (ethanol, methanol, etc.)

Samples from subjects with diagnosed T-Cell Lymphoproliferative disorders or suspected of T-Cell Lymphoproliferative disorders with negative T-Cell Clonality Testing results