Clinicopathological Features of Primary Bone Marrow Mature T and NK Cell Neoplasms
Ming Xie Department Of Pathology, William Beaumont Hospital, United States
Published on: 2018-08-22
neutropenia and thrombocytopenia. At our institution from 2003 to 2016, seventeen patients with primary bone marrow mature T and NK cell neoplasms were retrospectively studied, including 12 males and 5 females, with median age of 66 years (43 to 85). Nine patients had T cell large granular lymphocytic leukemia (T-LGL), 6 T cell neoplasm of undetermined significance (TNUS), and 2 chronic lymphoproliferative disorders of NK cells (CLPD-NK). The diagnosis of T cell neoplasm was confirmed by flow cytometry and immunohistochemical studies, as well as T cell receptor (TCR) gene rearrangement in the questionable samples. All patients had peripheral blood abnormalities as the clinical indication for bone marrow biopsy. Anemia was present in 12 patients, neutropenia 10, lymphocytosis 6 and thrombocytopenia 5. Positive EBER staining was seen in 3 samples. Two patients with TLGL showed abnormal karyotype at diagnosis, trisomy 22 in one, and del (6q) and del (7p) in another. There was no documented specific therapy targeted at the primary bone marrow mature T and NK cell neoplasm, except for 1 patient with T-LGL who received chemotherapy. Supportive treatment with occasional red blood cell transfusions was the principle management strategy for most patients. No death was documented directly from T and NK cell neoplasm in these 17 patients. The clinical presentation and peripheral blood findings of primary bone marrow mature T and NK cell neoplasm are often nonspecific, and TNUS usually is not expected clinically at the initial evaluation. Unlike T-LGL which is typically a disorder of CD8+ T cells, most primary bone marrow TNUS in this study are composed of CD4+ T cells. To our knowledge, this is the first study focusing on the clinicopathological features of primary bone marrow mature T and NK cell neoplasms as a collective group of diseases. Bone marrow biopsy is necessary for definitive diagnosis. Supportive and conservative management is the treatment of choice in most patients with overall favorable prognosis.
T Cell Large Granular Lymphocytic Leukemia; Chronic Lymphoproliferative Disorders of NK Cells; T Cell Neoplasm of Undetermined Significance; Bone Marrow Biopsy; Anemia
Mature T and NK cell neoplasms are relatively uncommon, and many of them are still poorly characterized. About 6.4% of the lymphomas found in bone marrow are mature T and NK cell lymphomas, and nearly 40% of them are secondary involvement by the previously diagnosed extramedullary T cell lymphomas. Primary bone marrow T and NK cell neoplasm may be the underlying etiology for anemia, leukopenia, and thrombocytopenia. However, very few publications have focused on the pathological and clinical features of these lesions as a group of diseases. This study is to evaluate the pathological features of primary bone marrow T and NK cell neoplasm and correlate with clinical features and patient management to better understand this rare, but important disease category.