The causes of lymphocytosis range from the benign self-limiting response seen in certain infections to frank malignancy (Table I). It is usually possible to differentiate benign from malignant lymphocytosis on the basis of the clinical picture, the blood film, and a small number of widely available investigations. The further investigation of the few remaining cases has been greatly aided by re...

The canonical Wnt signaling pathway is pathogenic in a variety of cancers. We previously identified aberrant expression of the Wnt pathway transcription factor and target gene lymphoid enhancer binding factor-1 (LEF1) in chronic lymphocytic leukemia (CLL). This suggested that the Wnt signaling pathway has a role in the biology of CLL. In this study, we performed a Wnt pathway analysis using gen...

We report the clinical, hematologic, and immunologic features of 18 preleukemic adult T cell leukemia (pre-ATL) cases with abnormal T lymphocytosis induced by human adult T cell leukemia-lymphoma virus (HTLV/ATLV). The patients were from the Nagasaki district, which is one of the most endemic areas of ATL in Japan. Pre-ATL is a subclinical T cell abnormality differing from ATL. It is characteri...

A 55-yr-old man presented with an 8-yr history of lymphocytosis. neutropenia. and infection. There was moderate splenomegaly without lymphadenopathy. and lymphocytosis of the blood (1 5.000-41 .200/cu mm) and bone marrow (30%): the latter also revealed no granulocytes more mature than the myelocyte. A diagnosis of leukemia could not be made from microscopic examination of the liver. spleen. or ...

Clinical vignette: A 49-year-old man with stage IV BRAFV600E-driven melanoma was initiated on twice-daily 960 mg of vemurafenib for treatment of progressive and recurrent subcutaneous metastatic disease of the left lower extremity. The patient's melanoma responded well to targeted BRAF inhibition. At treatment onset, hematologic parameters were all within normal limits; however, within three mo...

The canonical Wnt signaling pathway is pathogenic in a variety of cancers. We previously identified aberrant expression of the Wnt pathway transcription factor and target gene lymphoid enhancer binding factor-1 (LEF1) in chronic lymphocytic leukemia (CLL). This suggested that the Wnt signaling pathway has a role in the biology of CLL. In this study, we performed a Wnt pathway analysis using gen...

INTRODUCTION Persistent polyclonal B-cell lymphocytosis (PPBL) is a rare lymphoproliferative hematological disease characterized by binucleated lymphocytes, CD 19+ CD 5-lymphocytosis, and elevated levels of serum immunoglobulin M (IgM). It can rarely be associated with splenomegaly, though the disease usually remains indolent. CASE PRESENTATION We present a case of PPBL in a young man with ma...

Monoclonal B-cell lymphocytosis (MBL), a newly recognized entity found in approximately 3% of normal persons, precedes chronic lymphocytic leukemia. However, MBLs progress into overt malignancy only in a very minor portion of cases, thus raising the clinical concern of whether and how we can discriminate at diagnosis which rare cases will evolve into a fully fledged tumor. Understanding the mol...

We review the clinical manifestations and long-term outlook of patients with chronic natural killer (NK) cell lymphocytosis. After reviewing more than 1,500 peripheral blood lymphoid flow cytometry reports and molecular genetics data from patients with suspected large granular lymphocyte (LGL) proliferation, we identified 10 patients (median age at diagnosis, 60 years; range, 35 to 76 years; ma...