In addition, an IGK rearrangement, routinely tested exclusively in B-lineage ALL, was recognized as clonal in a T-lymphoblastic lymphoma (T-LL) case, and one TCRG clonal rearrangement was not previously identified because it was a very low represented clone (below the sensitivity of the homo/heteroduplex assay). This evidence concerns the gene TRGC1 and lymphoblastic lymphoma.