Utility of flow cytometry in subtyping composite and sequential lymphoma.

Composite lymphoma (CL) is defined as more than one distinct lymphoma variant occurring in the same anatomic site, and sequential lymphoma (SL) is defined as different lymphoma variants occurring at different sites or at different times in the same patient. The utility of flow cytometry immunophenotyping in evaluating CL and SL has only been investigated in a few single-case studies. To further define the utility of flow cytometry in evaluating these tumors, records were searched at two institutions. Cases representing high-grade progression of low-grade lymphoma were excluded. For each CL/SL, clinical data was obtained and morphology was evaluated in routinely processed H&E-stained tissue sections. Tumor components were subtyped using revised European-American classification (REAL) criteria. Follicle center components were graded using modified Rappaport criteria. Immunophenotype was determined using two-color flow cytometry and paraffin-section immunostains. Four cases were identified. Case 1, nodal follicle center, follicular, grade III plus marginal zone CL, showed two discrete populations of monoclonal B-cells that differed in their expression of CD10. Case 2, cutaneous lymphoplasmacytoid lymphoma followed by mesenteric non-Hodgkin's lymphoma (lymphoplasmacytoid plus follicle center, follicular, grade III) plus Hodgkin's disease CL, showed CD5-/CD10-/CD19+/kappa+ cells by flow cytometry in both tissue samples. The Hodgkin's disease component showed CD3-/CD15-/CD20-/CD30+ Reed-Sternberg cell variants in paraffin-section immunostains. Case 3 represented nodal follicle center lymphoma, follicular, grade I (CD3-/CD5-/CD10-/CD19+/kappa+) followed by cutaneous anaplastic large T-cell lymphoma (CD2+/CD4+/CD5+/CD19- cells with partial expression of CD3 and CD7). Case 4 represented cutaneous follicle center lymphoma, follicular, grade I (CD5-/CD10+/CD19+/CD23+/lambda+) followed by bone marrow B-cell small lymphocytic lymphoma (CD5+/CD10-/CD19+/CD23+/kappa+). Results show that flow cytometry is a potentially useful adjunct in characterizing CL and SL.

Relative frequencies and sites of presentation of lymphoid neoplasms in a community hospital according to the revised European-American classification.

Relative frequencies for common subtypes in the revised European-American classification of lymphoid neoplasms (REAL classification) have been reported. We determined the relative frequencies and sites of presentation of REAL subtypes at a 700-bed community hospital in central Illinois. A database was used to identify and prospectively catalogue all newly diagnosed lymphoid neoplasms from July 1, 1995 to March 1, 1998. The approach to diagnosis and subtyping incorporated morphologic features, immunophenotype, and clinical findings according to criteria proposed in the REAL classification. Of 347 lymphoid neoplasms diagnosed, 319 were subtyped in the REAL classification. Of these, 261 were B-cell neoplasms, 21 were T-cell neoplasms, and 37 were Hodgkin disease variants. Chronic lymphocytic leukemia/small lymphocytic lymphoma/prolymphocytic leukemia, diffuse large cell, and follicle center neoplasms were the most common B-cell subtypes. Large granular lymphocyte leukemia was the most common T-cell neoplasm. Nodular sclerosis was the most common Hodgkin disease variant. The relative frequencies in a US community hospital setting are similar to those reported in other studies. Differences are attributable to patient selection criteria, study group geographic location and racial composition, and/or referral patterns. Diverse REAL classification subtypes may be expected in US community hospitals.

Electrocardiographic changes in vitamin B6 deficient rats.

Serial electrocardiograms of vitamin B6 deficient rats show significant changes from those of rats on a complete diet. Animals fed a totally deficient diet from weaning grow slowly and die after about 12 weeks, often with a terminal weight loss. R and T amplitudes increase, then terminally decrease and are significantly greater than those of control animals. The PR interval is significantly shorter at times. Individuals have shown transient AV block, irregular sinus rhythm, wandering pacemaker, and inverted T waves. Autopsy findings include hypertrophy (89%), dilatation (61%) and atrial thrombi (44%). ECG's of adult animals remained normal for about three months after being fed the deficient diet. The two males developed premature ventricular contractions of several ectopic foci. Finally, split QRS complexes were observed. The female had a normal ECG until the final record at 234 days when some minor changes were seen. Extensive cardiomyopathic changes were found in two out of the three adults at autopsy.