Aggressive pleomorphic CD2+, CD3-, CD56+ lymphoma with t(5;9)(q31;q34) abnormality

CD56-positive lymphoma is a recently described entity which is characterized by predominantly extranodal involvement and an aggressive clinical course. We report one such case with involvement of the bone marrow and spinal cord at presentation, and associated with reactive hemophagocytic syndrome. The lymphoma cells had a highly pleomorphic appearance which is uncommon in CD56-positive lymphoma. Cytogenetic studies revealed a t(5;9)(q31;q34) abnormality. Analysis of more cases is required to determine if this is a recurring chromosomal translocation characteristic of the group of aggressive CD56-positive lymphoma.

Hepatosplenic gamma delta T-cell lymphoma. A distinctive aggressive lymphoma type

The T-cell receptor (TCR) expressed on the surface of most T-lymphocytes is of alpha beta type, and only a minority bear the gamma delta-TCR. Similarly, postthymic T-cell lymphomas rarely express gamma delta-TCR. Hepatosplenic gamma delta T-cell lymphoma is an uncommon entity that has so far not been widely recognized. We report one such case that has been comprehensively studied by multiple modalities and showed the unique occurrence of leukemic picture at presentation. The 39-year-old man presented with fever, marked weight loss, and massive splenomegaly. Peripheral blood showed thrombocytopenia and a white cell count of 5.8 x 10(9)/l, with 66% medium-sized lymphoid cells that had a round or folded nucleus, condensed chromatin and a moderate amount of pale blue cytoplasm. Splenectomy was performed and histologic examination of the spleen, bone marrow, liver, and abdominal lymph nodes demonstrated lymphoma infiltration with a predominantly sinusoidal pattern. Immunohistochemical studies of the lymphoma cells showed a T-cell phenotype: CD2+ CD3+ CD5+ CD7+ gamma delta-TCR+ alpha beta-TCR- CD56+ CD4- CD8- CD16- CD57-. Cytogenetic studies showed complex clonal chromosomal abnormalities of 44,X, -Y, -11, -22, + mar in 3/16 cells. Rearrangement of the TCR gamma chain gene was demonstrated by polymerase chain reaction; the TCR beta chain gene was partially chain reaction; the TCR beta chain gene was partially rearranged. The patient did not respond to single agent chemotherapy, but achieved clinical remission with combination chemotherapy. Based on the available data in the literature, hepatosplenic gamma delta T-cell lymphoma exhibits distinctive clinicopathologic features, and probably represents the neoplastic counterpart of splenic gamma delta T-lymphocytes. This disease is associated with a poor prognosis and usually relapses despite initial response to chemotherapy.

Refractory cytopenia with t(1;7),+8 abnormality and dysplastic eosinophils showing intranuclear Charcot-Leyden crystals: a fluorescence in situ hybridization study

A case of refractory cytopenia and marrow eosinophilia showing t(1;7) translocation and concomitant trisomy 8 is reported. The eosinophils were dysplastic, and showed the unique feature of intranuclear Charcot-Leyden crystal formation, giving rise to a 'lip-like' appearance. We speculate that this unusual cytologic feature resulted from abnormal precipitation of Charcot-Leyden crystal protein in the eosinophils. By fluorescence in situ hybridization using a chromosome 8 specific alpha-satellite probe, the abnormal eosinophils were shown to have derived from the abnormal clone. We postulate that the dysplastic clone might have retained a differentiation potential and be responsive to normal haemopoietic stimuli.

B-cell small lymphocytic lymphoma with circulating granular prolymphocytes and a novel trisomy 15 anomaly

A 53-year-old man presented with cervical lymphadenopathy and massive splenomegaly. Peripheral blood examination showed many prolymphocytes with cytoplasmic azurophilic granules, giving an initial impression of large granular lymphocytosis. The lymph node biopsy and immunohistochemical study findings, however, were more compatible with a diagnosis of B-cell small lymphocytic lymphoma. The circulating prolymphocytes showed restricted kappa light chain expression similar to the lymphoid infiltrate in the lymph node. Karyotypic analysis revealed trisomy 15, a chromosomal abnormality that has rarely been described in small lymphocytic lymphoma or chronic lymphocytic leukemia.

Pure red cell aplasia associated with thymic lymphoid hyperplasia and secondary erythropoietin resistance

Systemic disorders, often immune in nature, can sometimes be associated with the presence of thymic pathology. Thymic enlargement due to lymphoid hyperplasia or thymoma is a common occurrence in patients with myasthenia gravis. In patients with pure red cell aplasia, at least 10% to 15% of patients are found to have thymoma, usually of spindle cell or medullary type. Pure red cell aplasia with demonstrable thymic enlargement due to lymphoid follicular hyperplasia is distinctly unusual, and has not been previously reported. The authors report such a case developing in a patient with end-stage renal failure maintained on hemodialysis and erythropoietin therapy. Because the red cell aplasia resolved after thymectomy, the disease process was considered etiologically related to the reactive lymphoid hyperplasia.

Detection of Epstein-Barr virus in Hodgkin's disease occurring in an Oriental population

Like Burkitt's lymphoma, the strength of association of Epstein-Barr virus (EBV) with Hodgkin's disease occurring in different populations and clinical settings is highly variable, being 30% to 50% in Western countries, nearly 100% in Third World countries like Peru and Honduras, and nearly 100% in patients seropositive for human immunodeficiency virus. Data on the Oriental populations are very limited. Therefore, the current study was performed on the Chinese population of Hong Kong, where the incidence of Hodgkin's disease is low and EBV seroconversion occurs early in life. Twenty-three consecutive samples of Hodgkin's disease collected from 18 male and five female patients over a 12-year period were studied. The first age peak occurred in the second decade of life, and the second peak in the seventh decade. Using the sensitive and specific EBV-encoded RNAs (EBERs) in situ localization technique, positive labeling of the Reed-Sternberg cells and their variants was detected in five of five samples (100%) of mixed cellularity, nine of 16 samples (56%) of nodular sclerosing, one of one sample (100%) of lymphocyte depleted, and none of one sample (0%) of nodular lymphocyte predominant Hodgkin's disease. Further analysis of the data by age group yielded the following results: four of five (80%) for age younger than 15 years, three of nine (33%) for age 15 to 49, and eight of nine (89%) for age 50 or higher, confirming the reported strong association of EBV with Hodgkin's disease at the extremes of life. The overall positivity rate was 65%, which was intermediate between that reported in the Western populations and that in the Third World countries. These findings can be explained by the epidemiological pattern of Hodgkin's disease in Hong Kong, in which the first age peak is left-shifted to a younger age compared with that of Western populations (but not as early as that observed in Third World countries), moving the peak toward an age bracket in which Hodgkin's disease shows stronger association with EBV.

A study of the association of Epstein-Barr virus with Burkitt's lymphoma occurring in a Chinese population

There is a strong association (approximately 95%) of endemic Burkitt's lymphoma with Epstein-Barr virus (EBV), whereas the association is weak for the sporadic form occurring in Western countries (approximately 15%). In the Middle East, North Africa and South America, 60-80% of Burkitt's lymphomas harbour EBV. These epidemiological differences suggest that either the endemicity of EBV or socio-economic conditions, or both, may influence the pathogenetic role of EBV in Burkitt's lymphoma. Since only meagre data are available on Asians, this study was performed to address this issue by studying cases from Hong Kong, where EBV seroconversion occurs in the first few years of life but the socio-economic conditions approach those of Western countries. In situ hybridization for EBV encoded RNAs (EBERs) was performed on paraffin sections of 18 cases of Burkitt's lymphoma. Labelling of the neoplastic cells was detected in five cases (27.7%). In contrast, among 54 cases of B-cell lymphomas of various subtypes studied for comparison, signals for EBER were detected in only one case each of T-cell-rich large B-cell lymphoma, anaplastic large cell lymphoma and Reed-Sternberg-like cells occurring in B-cell chronic lymphocytic leukaemia/small lymphocytic lymphoma. The strong labelling with oligo-dT probe (which hybridized with the polyadenylated ends of mRNA) in all cases suggested that the negative results were genuine and not due to poor preservation of RNA in the tissues. Thus, among B-cell neoplasms occurring in Chinese, Burkitt's lymphoma shows a statistically stronger association (P < 0.01) with EBV than with other types of B-cell lymphoma.(ABSTRACT TRUNCATED AT 250 WORDS)

Endocrine malignancies that may mimic benign lesions

A variety of malignant tumors that occur in endocrine organs may mimic benign lesions histologically. In this article, a number of such tumors are selected for discussion, including several variants of papillary thyroid carcinoma (encapsulated follicular, diffuse sclerosing, diffuse follicular, macrofollicular, cystic, and stroma-rich), paucicellular anaplastic thyroid carcinoma, primary thyroid low grade B-cell lymphoma of mucosa-associated lymphoid tissue type, adrenocortical carcinoma, and parathyroid carcinoma. Emphasis is placed on the histological clues that are helpful for recognizing the malignant nature of these lesions.

Low frequency association of the t(2;5)(p23;q35) chromosomal translocation with CD30+ lymphomas from American and Asian patients. A reverse transcriptase-polymerase chain reaction study

Although cytogenetic data suggest that the t(2;5)-(p23;q35) translocation occurs in many cases of CD30+ lymphomas, the exact frequency of this event is still unknown. To clarify this issue and its epidemiological characteristics, we examined 37 formalin-fixed, paraffin-embedded specimens of CD30+ lymphomas from the United States and Hong Kong by reverse transcriptase-polymerase chain reaction (RT-PCR) for the status of the NPM and ALK genes, which are typically juxtaposed by the t(2;5) translocation. Thirty-four cases were classified as anaplastic large cell lymphomas (ALCL), 2 cases as non-anaplastic large cell lymphomas (LCL), and 1 case as the small cell variant of CD30+ lymphoma. The t(2;5) translocation was detected in 6 cases (16%), including 3 of 18 American patients and 3 of 19 cases from Hong Kong. All cases had a 185-bp NPM RT-PCR product as detected by Southern blot analysis, indicating adequate preservation of mRNA. The 6 positive cases were among 4 of 34 adult lymphomas, as compared with 2 of 3 childhood cases. Five of 17 T-lineage cases were t(2;5)-positive, compared with 1 of 15 B-lineage cases and none of the 5 null-cell or mixed lineage cases. Our results therefore show that t(2;5) occurs at a low frequency among CD30+ lymphomas, at least in our adult-dominated series.

Infrequent association of Epstein-Barr virus with CD30-positive anaplastic large cell lymphomas from American and Asian patients

CD30 (Ki-1)-positive anaplastic large cell lymphoma (CD30+ ALCL) is a morphologically and immunophenotypically distinct subset of non-Hodgkin's lymphoma. Although the presence of Epstein-Barr virus (EBV) has been well documented in a significant proportion of cases of Hodgkin's disease, another CD30+ malignancy, few studies have examined the association of EBV with CD30+ ALCL. These latter studies have produced conflicting findings. To further investigate the existence of a putative association of EBV with CD30+ ALCL, and whether this association, if present, shows geographic variation, we examined 34 formalin-fixed, paraffin-embedded specimens from cases of CD30+ ALCL from the United States and Hong Kong. Immunophenotypically, 15 cases were of B lineage, 15 cases were of T lineage, one case expressed both B- and T-cell markers, and three were of null lineage. A highly sensitive in situ hybridization method was performed with use of an antisense oligonucleotide probe to the EBV-encoded RNA (EBER-1). EBV-RNA was identified in 3 of 14 CD30+ ALCL specimens from Hong Kong patients and in 1 of 20 from the American patients. The EBER-1 signal was present in all or virtually all of the tumor cell nuclei in the three EBV-RNA-positive CD30+ ALCL Hong Kong cases, but was only focally present in the single EBV-positive American case. The latent membrane protein-1 (LMP1) of EBV was identified in only one of the four positive cases, a Hong Kong case. Our results suggest that in contrast to Hodgkin's disease, EBV has no significant association with CD30+ ALCL.

Large granular lymphocyte leukemia. A study of nine cases in a Chinese population

Large granular lymphocyte (LGL) leukemia is a neoplastic disorder of lymphocytes that is characterized by the presence of prominent cytoplasmic granules, and involves the proliferation of at least two distinct cell types, T cells and natural killer (NK) cells. The authors report the clinical and pathologic features of 9 Chinese patients with LGL leukemia, who represented 14% of 64 cases of chronic lymphoproliferative disorders diagnosed at their centers in 3 years. Three different groups could be defined on immunophenotypic and clinical grounds. The first group of 4 cases were CD2+CD3+CD4-CD8+. With the exception of a pediatric case, these cases ran an indolent course that was similar to the T-cell LGL leukemia most common in Western patients. However, thrombocytopenia and pure red cell aplasia were more common in the patients in this study, which was similar to the experience in Japanese patients. The second group of two cases were CD2+CD3+CD4+CD8-, and appeared to have worse outcomes than the first group. The third group of 3 cases were CD2+CD3-CD4-CD8-CD56+. Although phenotypically similar to the NK-cell LGL leukemia reported in Western patients, these cases were clinically more aggressive than their Western counterparts. This study is the first to report comprehensively the different types of LGL leukemias in Chinese patients, and provides useful information on the similarities and similarities and differences of these disorders as compared to those cases in the West.

A proposal for classification of lymphoid neoplasms (by the International Lymphoma Study Group)

A new classification of lymphoid neoplasms, mostly based on existing terminology, is proposed by the International Lymphoma Study Group. The proposed classification was reached through a consensus of the members, despite their diverse backgrounds, and consists of a listing of currently recognized clinicopathological entities. These tumours are divided into three major categories: B-cell neoplasms, T-cell and postulated natural killer cell neoplasms, and Hodgkin's disease. The characterization of each entity is based on a synthesis of all available information. This concept departs from a purely morphological approach to lymphoma classification, which is considered to be inadequate, because many biologically distinctive lymphoma types can exhibit a broad and overlapping morphological spectrum. Some entities are provisional, pending further data to confirm that their recognition is reproducible. The salient clinicopathological features of each entity are summarized in this review.

Specific association of Epstein-Barr virus with lymphoepithelial carcinoma among tumors and tumorlike lesions of the salivary gland

The Epstein-Barr virus (EBV)-encoded RNAs in situ localization procedure is a convenient, highly sensitive, and highly specific technique that is applicable to routinely fixed, paraffin-embedded tissue sections; this technique can be used for the study of the association and, hence, the possible causal role of EBV in tumors. This study was performed to elucidate whether EBV plays a role in the pathogenesis of tumors that arise in the salivary glands, since the salivary gland is known to be a reservoir for EBV replication. Cases that were selected included 61 examples of various benign and malignant neoplasms, as well as tumorlike conditions of the major and minor salivary glands. Only the five cases of lymphoepithelial carcinoma (so-called malignant lymphoepithelial lesion) and the single case of metastatic nasopharyngeal undifferentiated carcinoma showed staining with EBV-encoded RNAs, whereas negative findings were found in all of the other cases. In the cases with positive results, all of the neoplastic epithelial cells showed strong nuclear signals, but the lymphoid cells were negative. The consistent association of EBV with lymphoepithelial carcinoma of the salivary gland suggests that the virus probably plays a causal role in this tumor, at least in the Asian population, whereas there is no evidence for a causal role of EBV in other primary tumors of the salivary gland.

Fine-needle aspiration cytologic diagnosis of Kikuchi's lymphadenitis. A report of 27 cases

Kikuchi's lymphadenitis is a self-limiting condition typically affecting young patients. Surgical biopsy is unnecessary if a firm diagnosis can be rendered by fine-needle aspiration cytology (FNAC). The authors report the FNAC findings for 27 cases, including 24 female and 3 male patients aged 12 to 43 years. Histologic sections of FNAC cell blocks and excisional biopsy specimens were available in 26 and 9 cases, respectively, for confirmation of the diagnosis. In the smears, karyorrhectic and granular debris were mixed with two distinctive cell types: (1) phagocytic histiocytes with peripherally placed "crescentic" (sometimes elongated or twisted) nuclei and abundant cytoplasm containing phagocytosed karyorrhectic or eosinophilic granular debris, easily distinguishable from tangible-body macrophages, which possessed central round nuclei, and (2) medium-sized cells possessing eccentrically placed round nuclei, fairly condensed chromatin, and a moderate amount of amphophilic cytoplasm, consistent with plasmacytoid monocytes. Also present were nonphagocytic histiocytes with twisted nuclei and delicate chromatin and immunoblasts that sometimes showed atypical features such as irregular foldings of the nuclei. Neutrophils were sparse or absent. Review of the FNAC findings of 50 lymph nodes involved by various reactive processes, tuberculosis, and lymphoma for comparison showed that although tangible-body macrophages and debris were not uncommon, very few phagocytic histiocytes with crescentic nuclei were observed, in only 2 cases; plasmacytoid monocytes were observed in 4 cases. The constellation of features described above permits diagnosis of Kikuchi's lymphadenitis by FNAC. Because of morphologic similarities between lupus lymphadenitis and Kikuchi's lymphadenitis, however, serologic studies are warranted to exclude systemic lupus erythematosus.

Histologic changes in the breast after fine-needle aspiration

Fine-needle aspiration biopsy (FNAB) of the breast has been widely used in many centers worldwide for the initial management of patients with breast lumps. However, little has been written on the morphologic changes secondary to this commonly applied procedure. Thus we performed a retrospective study on 184 consecutive breast-excision specimens with a history of FNAB. Seventeen cases (9.2%) showed changes definitely attributable to the FNAB procedure, including three cases of near total destruction of the lesion as a result of hemorrhage (one case) or infarction (two cases), focal hemosiderin deposition (seven cases), hemorrhage with organization at the periphery (six cases), and a case of ductal papilloma showing a previously undescribed occurrence of benign epithelial implantation. The latter exhibited alarming histologic features simulating invasive carcinoma by virtue of the presence of small narrow tubules with mild cellular atypia haphazardly distributed in the fibrogranulation tissue around the papilloma; the tubules were confirmed to be benign by the presence of muscle-specific actin-positive myoepithelial cells. Other changes were possibly attributable to the FNAB procedure, including linear necrosis in the peripheral portion of the tumor (six cases), intraluminal hemorrhage in fibroadenoma (five cases), and multicentric hemorrhage in the mucinous carcinomas (four cases). We conclude that the rare occurrence of extensive tissue necrosis after FNAB can pose great difficulties in definitive diagnosis of the lesion in the subsequent excision specimen. Other changes are relatively minor, but the occurrence of benign implantation after FNAB may lead to an erroneous diagnosis of invasive carcinoma.