1/10. t(2;5) associated with a histiocytic-monocytic neoplasm. We describe a patient with a neoplasm derived from the histiocytic-monocytic lineage associated with t(2;5) detected by FISH. The patient presented with bone marrow involvement, no organomegaly and subsequently developed a leukaemic picture. The clinical course was aggressive and the patient died four months from diagnosis. Cell morphology, immunophenotype (CD30-, EMA-, Lisozyme , cy CD68 and CD45 ) and dna analysis showing germ-line configuration of the Ig/TCR chain genes ruled out the diagnosis of anaplastic large cell lymphoma (ALCL). This unusual case ilustrates that t(2;5) is not exclusive for ALCL but may be found in a few cases of rare neoplasms derived from the histiocytic-monocytic cells. ( info) |
2/10. Cutaneous true histiocytic malignancy: true histiocytic lymphoma. True histiocytic malignancies (THM) are controversial disorders that are being re-evaluated with modern cellular and molecular biology techniques. True histiocytic lymphoma (THL) is a low-incidence, poor-prognosis THM. It mainly affects the skin, gastrointestinal tract, and bone tissues. Occasionally, skin lesions are the presenting clinical features. A patient with initially cutaneous THL is described. This and other reported cases confirm that THM are a nosologic entity by themselves. ( info) |
| The authors describe a rare tumor with overlapping features of true histiocytic sarcoma and interdigitating dendritic cell sarcoma occurring in infancy. A 3-month-old boy presented with hepatosplenomegaly and abdominal distention. He presented a diagnostic challenge at initial presentation despite extensive investigations. On follow-up at age 16 months he had progressive splenomegaly, thrombocytopenia, and worsening coagulopathy. A diagnosis of histiocytic sarcoma with interdigitating dendritic cell differentiation was established after an open biopsy of liver and spleen. A repeat liver biopsy coupled with splenic biopsy is recommended in young children with unexplained hepatosplenomegaly and thrombocytopenia. ( info) |
4/10. histiocytic sarcoma: a study of five cases including the histiocyte marker CD163. histiocytic sarcoma (HS) is a rare but controversial hematopoietic neoplasm. In the past, malignancies have been misclassified as histiocytic tumors due to overlapping histologic features and inadequate phenotypic data. CD163, a recently characterized hemoglobin scavenger receptor, appears to be a 'specific' marker of histiocytic lineage and a promising diagnostic tool for evaluating histiocytic neoplasms. Five cases of HS were studied to further elucidate the clinicopathologic features of these rare tumors and to demonstrate the diagnostic utility of CD163. Criteria for diagnosis included histologic and immunohistochemical evidence of histiocytic differentiation, CD45 positivity, and exclusion of lymphoid, epithelial, melanocytic and dendritic cell phenotype. Sites of disease included the colon (two cases), palate, inguinal lymph node, and testis. The clinical course was aggressive in 4/5 patients (survival=2-15 months). One patient with localized disease of the palate, survived 17 years after diagnosis. All patients with poor survival had tumors > or =3.5 cm. Histologically, all cases showed diffuse architecture with large, discohesive polygonal cells. Spindling of cells was focally noted. Hemophagocytosis was identified in 3/5 cases. A prominent inflammatory background was present in 4/5 tumors. All cases were immunoreactive for CD45, CD163, CD68, and lysozyme. S-100 was focally positive in 4/5 cases. antibodies for melanocytic, epithelial, lymphoid, and dendritic cell markers were negative. Molecular studies showed monoclonal IgH gene rearrangements in three cases. Our findings suggest that HS is an uncommon neoplasm frequently extranodal in presentation and aggressive in behavior, with rare exceptions. Stage of disease and possibly tumor size are significant prognostic indicators. Molecular studies remain controversial in the diagnosis. The morphologic and phenotypic features are relatively uniform; however, the diagnosis requires exclusion of more common neoplasms by extensive immunophenotypic studies. CD163 appears to be a specific histiocytic marker and is important in establishing the diagnosis of HS. ( info) |
5/10. Malignant melanoma with osteoclast-like giant cells: an unusual host response: immunohistochemical and ultrastructural study of three cases and literature review. Melanomas with unusual histologic features are very rarely reported in the literature and demonstrate the diversity of melanocytic expression. Three cases of malignant melanoma with osteoclast-like giant cells are reported. Two cases showed undifferentiated malignant cells without melanin pigment and one showed spindled cell morphology. immunohistochemistry showed that the osteoclast- like giant cells expressed CD68, but not melanocytic markers (HMB45, Melan-A, and S100). Ultrastructural analysis further supports that these cells are reactive histiocytes rather than transformed malignant cells. This suggests they represent an unusual host response, similar to those rarely observed in other neoplasms. awareness of this entity is important to avoid misdiagnosis of melanoma as a histiocytic tumor. Since only few cases have been reported, greater recognition and documentation may help to evaluate the prognosis of such cases with unusual morphology. ( info) |
| histiocytic sarcoma is a rare malignant neoplasm. It is well-known the association of Langerhans' cell histiocytosis with Hodgkin's disease but only few cases of histiocytic sarcoma associated with Hodgkin's disease was reported. We present the case of 20-years-old female patient with Hodgkin's disease with a sternal tumor mass which was diagnosed as histiocytic sarcoma. The diagnostic was established immunohistochemically, using a large battery of antibodies (S-100, CD 68, CD 34, CD 15, CD 30, Vim, NFAP) and by electron microscopy which revealed the lack of the Birbeck granules in the malignant proliferated histiocytes. ( info) |
| The majority of cases of intravascular lymphomatosis are B-cell lymphomas with only the occasional case being of T-cell type. We report a case of intravascular lymphomatosis in which the proliferating cells were of histiocytic type; the tumour has recurred following treatment. ( info) |
8/10. Regressing atypical histiocytosis: report of two cases with progression to high grade T-cell non-Hodgkin's lymphoma. Two cases of regressing atypical histiocytosis (RAH) are presented. Both patients followed a typical regressing/relapsing course for several years before progression to high-grade neoplasia. In both cases these high-grade tumors were diagnosed as T-cell non-Hodgkin's lymphoma on histopathologic and immunophenotypic grounds, and demonstrated T-cell receptor beta chain (TCR beta) gene rearrangement on Southern blotting. The original cases of RAH were considered to be indolent neoplasms of histiocytic lineage. A single case of a patient with RAH demonstrating TCR beta and gamma gene rearrangements has been described. Our cases lend further weight to the proposition that RAH is a neoplasm of T-cell lineage, and ultimately of aggressive potential. This description accords with current thinking that many of the conditions previously classified as malignant histiocytosis would be better classified as T-cell non-Hodgkin's lymphoma. ( info) |
9/10. "Pseudoneoplastic" leprosy. leprosy revisited. A 70-year-old Italian man with a history of squamous cell carcinoma of the lung presented with a nodular skin eruption. He had traveled extensively in india and sri lanka. The nodules were well demarcated and measured up to 3.5 cm in diameter. Histologically, there was a proliferation of spindled and polygonal cells with focal and relatively inconspicuous cytoplasmic vacuolation. A macrophage-monocyte lineage for the cells was confirmed by paraffin section immunohistochemistry, using the monoclonal antibodies anti-CD45, MAC-387, KP-1, UCHL-1, MT-1, L26, and MB2. Infiltrating borders, extension of the lesion into the subcutis, and involvement of small dermal nerves and eccrine glands initially suggested the possibility of a "histiocytic" neoplasm of indeterminate biological potential. However, air-dried and Giemsa-stained material from a fine-needle aspirate of one cutaneous nodule showed needle-shaped intracellular "negative images," and acid-fast stains revealed a large number of intracytoplasmic bacilli in virtually all of the vacuolated lesional cells. Furthermore, a second skin nodule that was excised 3 weeks after initial presentation showed the typical morphology of lepromatous leprosy. The clinicopathologic features of this case demonstrated several similarities with those of so-called "histoid" leprosy. Unusual morphologic variants of leprosy need to be considered in the interpretation of unusual "histiocytic" infiltrates in order to avoid a mistaken diagnosis of neoplasia, regardless of the geographic locale in which the patient is evaluated. ( info) |
10/10. Complex chromosomal rearrangements associated with congenital erythrophagocytotic histiocytosis. We describe a patient with a congenital malignant blood disorder and a constitutional de novo chromosomal rearrangement that includes four breakpoints. By conventional cytogenetic analysis an obviously reciprocal balanced translocation with the breakpoints 1p36 and 5q11.2 was diagnosed. Due to a suspicious dark band in the breakpoint area of 1p a more detailed analysis of the breakpoints was performed using microdissection and reverse chromosome painting. This revealed a small inversion at 1p36 that must have occurred prior to the reciprocal translocation. The three breakpoints in chromosome 1 (1p36.11, 1p36.21 and 1p36.31) are within or close by regions known to contain tumor suppressor genes. The chromosomal rearrangement might have resulted either in a submicroscopic deletion, in loss of heterozygosity of one or more imprinted genes, or in gene position effects as possible explanations for the clinical course of our patient. ( info) |