Sinus histiocytosis with massive lymphadenopathy (SHML), also known as Rosai-Dorfman disease, is a disorder of unknown cause. Rarely, patients with SHML also have malignant lymphoma, usually involving anatomic sites different from those involved by SHML. We report four patients in whom SHML and malignant lymphoma were identified in the same lymph node biopsy specimen. The SHML in each case was present as a small focus, less than 1 cm. Immunohistochemical studies showed that the abnormal histiocytes were positive for S-100 and negative for CD1a. The malignant lymphomas included two cases of follicular lymphoma and two cases of Hodgkin's disease, nodular lymphocyte predominant type. The presence of SHML in these patients did not impact clinical decisions, and there was no evidence of SHML elsewhere. Thus, the presence of focal SHML associated with malignant lymphoma in these cases was an incidental histologic finding that seems not to have had any clinical significance.

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Mantle cell lymphoma (MCL) is a distinct type of non-Hodgkin's lymphoma (NHL) characterized by the t(11;14)(q13;q32), in which the ccnd1 gene is juxtaposed with the immunoglobulin heavy chain gene, resulting in up-regulation of cyclin D1. Cyclin D1 overexpression is a useful finding that supports the diagnosis of MCL. In this study, we used a 5' 3 3' exonuclease-based real-time reverse-transcriptase polymerase chain reaction (RT-PCR) method to quantify cyclin D1 mRNA in 108 B-cell NHL and nonneoplastic specimens, including 25 cases of MCL. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) was also quantified to normalize cyclin D1 mRNA levels, and the data were expressed as a cyclin D1 to GAPDH ratio. At each anatomic site, MCL cases had higher cyclin D1 levels than other types of NHL or nonneoplastic specimens, without overlap. For example, in lymph node specimens, the median cyclin D1/ GAPDH ratio was 147 (range, 94 -160) in MCL, compared with 8.6 (range, 4 -18) in chronic lymphocytic leukemia/small lymphocytic lymphoma; 5.8 (range, 1.8 -24) in follicular lymphoma; 4.8 in one case of marginal zone lymphoma; and 20.2 (range, 5.8 -44) in reactive specimens. Statistical analysis using oneway analysis of variance (ANOVA) showed that MCL cases had significantly higher cyclin D1 levels than other groups (P < .05). In peripheral blood specimens involved by MCL, cyclin D1 levels correlated with extent of involvement. We conclude that this real-time RT-PCR method to quantify cyclin D1 expression is helpful in distinguishing MCL from other types of B-cell NHL and from nonneoplastic specimens. This method is rapid, can be applied to the analysis of fluid specimens, and obviates the need for time-consuming and laborious detection methods that are required by traditional semiquantitative RT-PCR methods.

We describe our experience using two real-time polymerase chain reaction (PCR) assays for detecting the t(14;18)(q32;q21) in a large series of nonHodgkin's lymphomas (NHLs). These assays utilize the 533 exonuclease activity of Taq polymerase, which cleaves a probe labeled with a fluorescent reporter dye at its 5 end and a quencher dye at its 3 end during the extension phase of PCR. In a previous study, Luthra and colleagues developed these real-time PCR assays for detecting the t(14;18) involving the major and minor breakpoint cluster regions of the bcl-2 gene and assessed a small number of NHLs. In this larger study, we analyzed 135 NHLs, 6 Hodgkin's disease, 10 reactive biopsy specimens, and 11 peripheral blood specimens. The NHL group included 46 of 70 (65.7%) follicular NHLs, 1 of 2 (50%) diffuse small cleaved cell NHLs, and 13 of 24 (54.2%) diffuse large B-cell NHLs with the t(14;18) detected by conventional PCR methods. There was excellent agreement between the realtime and conventional PCR assays with overall concordance in 160 of 162 (98.8%) specimens. For the NHLs, concordance was found in 134 of 135 (99.3%) specimens. Disagreement was observed in one case of follicular NHL in which the real-time PCR assay detected bcl-2 minor breakpoint cluster region/JH DNA fusion sequences and the conventional method was negative. The overall concordance for 10 benign biopsy specimens and 11 normal peripheral blood samples was 20 of 21 (95.2%). One lymph node biopsy specimen that showed reactive follicular hyperplasia was positive for the bcl-2 minor breakpoint cluster region/JH DNA fusion sequences detected by the real-time PCR assay but was negative by conventional PCR methods. This patient had no clinical evidence of NHL. We conclude that realtime PCR assays for detecting the t(14;18) are sensitive, specific, and more convenient than conventional PCR methods.KEY WORDS: Non-Hodgkin's lymphoma, Polymerase chain reaction, Real-time, t(14;18)(q32;q21). Mod Pathol 2000;13(6):661-666Follicular lymphoma is the most common type of non-Hodgkin's lymphoma (NHL) in the United States (1). Up to 90% of follicular lymphomas carry a reciprocal balanced chromosomal translocation, the t(14;18)(q32;q21), involving the bcl-2 gene on chromosome 18q21 and the immunoglobulin heavy chain gene in 14q32. The majority of the breakpoints on chromosome 18 are tightly clustered in two regions: the major (MBR) and minor (MCR) breakpoint cluster regions (2-6). The clustering of these breakpoints makes these regions amenable to PCR analysis and has led to development of highly sensitive PCR assays to detect the t(14;18) (7-9). Real-time PCR assays that utilize the 5Ј33Ј exonuclease activity of Taq polymerase haved been developed (10 -12). In these assays, a nonextendable oligonucleotide probe is designed to anneal downstream to one of the PCR primers and is labeled with a fluorescent reporter dye at its 5Ј end and a quencher dye at its 3Ј end. During the extension phase of PCR, the 5Ј33Ј exonuclease activity of Taq polymerase cleaves the reporte...

Background: Diseases associated with coal mine dust continue to affect coal miners. Elu-