B-cell lymphoproliferative disorder complicated by a natural killer cell lymphoproliferative disorder of granular lymphocytes associated with T-cell gene rearrangement: case report and review of the literature.

We report an unusual case of natural killer cell lymphoproliferative disorder of granular lymphocytes associated with a T-cell receptor (TCR)-beta gene rearrangement. The patient developed the disorder 1 month after cessation of fludarabine therapy for a B-cell lymphoproliferative disorder. The B-cell lymphoproliferative disorder was no longer detectable when the natural killer cell lymphoproliferative disorder persisted. Review of the literature reveals only one reported case of natural killer cell lymphoproliferative disorder of granular lymphocytes associated with a TCR-delta gene rearrangement.