Lymphoma-like monoclonal B cell lymphocytosis in a patient population: biology, natural evolution, and differences from CLL-like clones

High-count monoclonal B cell lymphocytosis (MBL) with a chronic lymphocytic leukemia (CLL) phenotype is a well-known entity, featuring 1-4% annual risk of progression towards CLL requiring treatment. Lymphoma-like MBL (L-MBL), on the other hand, remains poorly defined and data regarding outcome are lacking. We retrospectively evaluated 33 L-MBL cases within our hospital population and compared them to 95 subjects with CLL-like MBL (C-MBL). Diagnoses of L-MBL were based on asymptomatic B cell clones with Matutes score < 3, B cells < 5.0 × 10³/μl, and negative computerized tomography scans. We found that median B cell counts were considerably lower compared to C-MBL (0.6 vs 2.3 × 10³/μl) and remained stable over time. Based on immunophenotyping and immunogenetic profiling, most L-MBL clones did not correspond to known lymphoma entities. A strikingly high occurrence of paraproteinemia (48%), hypogammaglobulinemia (45%), and biclonality (21%) was seen; these incidences being significantly higher than in C-MBL (17, 21, and 5%, respectively). Unrelated monoclonal gammopathy of undetermined significance was a frequent feature, as the light chain type of 5/12 paraproteins detected was different from the clonal surface immunoglobulin. After 46-month median follow-up, 2/24 patients (8%) had progressed towards indolent lymphoma requiring no treatment. In contrast, 41% of C-MBL cases evolved to CLL and 17% required treatment. We conclude that clinical L-MBL is characterized by pronounced immune dysregulation and very slow or absent progression, clearly separating it from its CLL-like counterpart.

Variant of lymphocytic infundibulo-neurohypophysitis presenting with unique clinical and radiological features

Lymphocytic hypophysitis (LYH) is a chronic inflammation that primarily affects the pituitary gland. This disorder has recently been classified into lymphocytic adenohypophysitis (LAH), lymphocytic infundibulo-neurohypophysitis (LINH), and lymphocytic infundibulo-panhypophysitis (LIPH) according to the affected area. We report a case of LINH in a 68-year-old woman who presented with diabetes insipidus (DI). In this case, the posterior lobe was affected in both endocrinological assessment and magnetic resonance imaging (MRI) findings. In contrast, the anterior pituitary was not affected in endocrinological assessment but was affected in MRI findings. Indeed, the patient did not develop hypopituitarism. We believed that these clinical and radiological features were unique in regard to the classification of LYH. To confirm the classification of LYH and the distinction from pituitary adenoma, a pituitary biopsy was performed. Based on the pathological and endocrinological assessment, the patient's disorder was finally diagnosed as a variant of LINH. Current evidence recommends that surgical intervention for LYH should be avoided because the natural course of LYH is essentially self-limiting. Therefore, the accumulation of the knowledge of many variants of LYH is important for the preoperative differential diagnosis of pituitary masses. Our clinical observation could be useful for avoiding unnecessary surgical intervention.

Unusual lymphocyte subset distribution in some depressed patients

Depression has been previously associated with immunologic dysfunction. The lymphocyte subsets of 10 patients with major depression were found to show a mean T4-T8 (helper-suppressor) ratio lower than that of controls, a difference attributable to increased numbers of suppressor cells in the depressed group. One possible cause of increased suppressor cells is prior or current viral infection.

Role of immunotyping in chronic lymphocytosis: review of the natural history of the condition in 145 adult patients

We investigated the clinical value of immunotyping in 145 consecutive adult patients with absolute or relative lymphocytosis: 132 (91%) had B-cell lymphocytosis, 5 (4%) had T-cell lymphocytosis, 2 (1%) had hairy cell leukemia, and 6 (4%) had reactive lymphocytosis. Of the five patients with T-cell lymphocytosis, four were best categorized as having T gamma-chronic lymphoproliferative disease and had an indolent clinical course. Of the 132 patients with B-cell lymphocytosis, 121 (92%) had B-cell chronic lymphocytic leukemia (B-CLL), and 11 (8%) had small cleaved ("lymphosarcoma") cell leukemia. Patients with small cleaved cell leukemia had a worse clinical outcome than did those with B-CLL. We further analyzed the surface immunoglobulin (sIg) and CD20 (B-1) antigen expression patterns in B-CLL to determine whether any correlation existed with clinical outcome. A subset of patients with B-CLL in whom sIg was expressed in less than 20% of their lymphocytes had the best clinical outcome. HLA-DR (Ia-like) antigen typing helped identify B-CLL cases with minimal or no sIg expression. CD20 (B-1) antigen was weak or undetectable in most cases of B-CLL. Patients with B-CLL who had CD20 (B-1) in more than 20% of their lymphocytes did not have a different prognosis. Our data provide the incidence and natural history of the various subsets of CLL in a series of patients at a single institution. The type and extent of immunotyping necessary and practical in the clinical management of patients with CLL are explored.