Interdigitating cell sarcoma (ICS). Evidence of interdigitating cell origin, immunocytochemical studies with monoclonal anti-ICS antibodies

Relapse in dermatofibrosarcoma protuberans: A histological and molecular analysis

BACKGROUND

Dermatofibrosarcoma protuberans (DFSP) is a rare low grade tumor with a locally aggressive behavior and low metastatic potential.

OBJECTIVES

To evaluate the factors that are associated with relapse in DFSP. Methods Retrospective analysis of medical records from 61 patients with dermatofibrosarcoma. Fluorescence in situ hybridization was used to detect translocations.

RESULTS

Of 61 patients, 6 experienced a relapse. No patient with resection margins greater than 3 cm had a recurrence. One relapse was observed in a patient treated with at least 2 cm margins and 4 relapses occurred in 16 patients whose margins were below 2 cm (P = 0.018). The frequency of translocations was 77.8%. The recurrence rate was lower in patients with translocation, but this difference was not significant. Immunohistochemical markers did not correlate with recurrence rates, but greater FasL expression was associated with recurrence in patients with margins smaller than 3 cm.

CONCLUSIONS

Surgical margins smaller than than 2 cm are related to higher recurrences in dermatofibrosarcomas. In this analysis a 2 cm margin was acceptable for treatment. Between all the immunohistochemical markers analyzed, only FasL was associated with a higher recurrence rate in patients with margins smaller than 3 cm.

Alkaline phosphatase expression during monocyte differentiation. Overlapping markers as a link between monocytic cells, dendritic cells, osteoclasts and osteoblasts

Human monocytes (Mo) in culture can be differentiated into macrophages (M phi), dendritic cells (DC) and osteoclasts. In addition, we have established a Mo-derived in vitro granuloma model which here was compared with ex-vivo isolated foreign body granuloma cells. In these models overlapping phenotypes developed between monocyte-derived dendritic cells (MoDC), osteoclasts, M phi, and osteoblasts. In Mo cultures granulomas were induced by immobilized particulate material. AP activity (osteoblast marker) was found to be co-expressed with cytoplasmic tartrate resistant acid phosphatase (TRAP) as a marker of osteoclasts. While proliferating, the number of AP+ cells decreased, being replaced by cells co-expressing the osteoclast markers vitronectin receptor (VNR) and TRAP. Coexpression of the Mo/M phi marker CD68 with AP or VNR confirmed the monocytic origin of the cells. When Mo were treated with interleukin-4 (IL-4), the number of AP+ cells markedly increased and remained stably expressed over 12 days. In explants from ex vivo granulomas obtained from endoprosthetic revisions the major cell type was the AP+ cell co-expressing CD68. The bone-specific alkaline phosphatase (BAP) as a marker of osteoblasts was detected by FACS analysis in the ex vivo granuloma cells. By RT-PCR the mRNA for osteocalcin, which is a highly specific marker for osteoblasts, was detected. From our results we conclude an ontogenetic relationship between macrophages, DC and osteoclasts. Furthermore, the data suggest a transdifferentiation between Mo and osteoblasts.

Hodgkin's disease expressing follicular dendritic cell marker CD21 without any other B-cell marker: a clinicopathologic study of nine cases

Reed-Sternberg (RS) and Hodgkin's (H) cells are considered to be the neoplastic cells in Hodgkin's disease (HD). Although most data suggest their lymphoid origin, the nature of these cells still remains a subject of controversy. Recently, a number of RS cells have been found to express an antigen that is also present on follicular dendritic cells (FDCs), asserting FDCs as the possible progenitor cells of H-RS cells. This prompted us to investigate whether these CD21-positive cases had distinct clinicopathologic characteristics. In a series of 94 examined cases of HD, we identified 9 CD21-positive ones (4 of 37 cases of nodular sclerosis, 1 of 41 mixed cellularity, and 4 of 12 lymphocyte depletion HD) without any other B-cell marker on paraffin sections. The patients varied in age from 16 to 82 years (median, 50 years) and included six men and three women. They had superficial or mesenteric lymphadenopathy without hepatosplenomegaly. Peripheral blood leukocytosis was seen in three patients. The clinical course was indolent, and all patients but one achieved an initial complete response with HD-based treatment regimens, although three of them relapsed. Morphologically, two subgroups could be delineated. Six of the cases were characterized, besides by the classic RS cells, by a varying number of the cells with the distinctive walnutlike or cerebrumlike nuclei and cytologically with cytoplasmic processes. Their fine structural examination also revealed villous processes, but no desmosomes. The other three cases had multinucleated RS cells often with triangular nuclei, but not cytoplasmic processes. The percentage of CD21-positive tumor cells ranged from less than 10% to 60% among the H-RS cells. These RS cells were positive for CD30 (9 of 9), CD15 (7 of 9), CD68 (1 of 8), fascin (8 of 8), S-100 protein (1 of 7), and epithelial membrane antigen (2 of 8) on paraffin sections. Notably, of eight cases examined on frozen sections, two showed immunostaining for DRC1, CD35, R4/23, and Ki-M4p. Only CD35 was also detected in the other two cases. Genotypic investigation showed germline configuration of the T-cell receptor beta and gamma chain genes and the immunoglobulin heavy chain gene in all eight cases examined. In situ hybridization showed Epstein-Barr virus sequences in four cases, three of which were examined by the terminal region analysis and showed the Epstein-Barr virus to be monoclonal. We concluded that in a small proportion (9.6%) of HD, H-RS cells might be derived from FDCs and that they appear to represent a distinct pathologic variant based on morphologic and phenotypic traits within the framework of HD.

Extranodal follicular dendritic cell sarcoma of the palate

Follicular dendritic cell tumors are uncommon and usually occur in lymph nodes. We report the case of a follicular dendritic cell tumor that occurred in the palate of a 14-year-old boy and manifested itself as a nodular mass. Histologically, the neoplasm consisted of spindle-shaped or oval-shaped cells with eosinophilic cytoplasms and nuclei with delicate, dispersed chromatin. The lesional cells were principally arranged in diffuse, fascicular patterns with vaguely whorled or storiform areas. Focal multinucleate tumor giant cells and lymphocytes were observed throughout the neoplasm. Immunohistochemically, tumor cells were positive for the follicular dendritic cell markers CD21, CD35, and CD23 and for S-100 protein, CD68, and muscle-specific actin. Tumor cells were negative for LCA, CD20, EMA, CK (AE1/AE3), HMB45, and CD34. Lymphocytes were positive for LCA and CD45RO. Although follicular dendritic cell sarcoma is a very uncommon tumor, it should be included in the differential diagnosis of tumors in this location.

The S100 family of multipurpose calcium-binding proteins

Antibodies reactive with S100 protein are useful markers in a diagnostic immunohistochemistry laboratory dealing with cutaneous tumors. However, S100 protein is not a single protein but instead a group of S100 proteins with diverse functions. S100 proteins constitute a family of acidic calcium-binding proteins that are important in intracellular calcium metabolism. Recent evidence that some S100 proteins are secreted makes it likely that they are also involved in cell-cell interactions. The exploration of the status of the different members of the S100 family may yield not only diagnostic clues but also relevant functional information about the cells. Considerable recent progress has been made in our understanding of S100 proteins. This review surveys some of these findings that may be either directly or indirectly relevant to cutaneous pathology.

Follicular dendritic cell tumor: report of 13 additional cases of a distinctive entity

Follicular dendritic cell (FDC) tumor is an extremely rare malignant neoplasm with approximately 17 well-documented cases in the literature. We report 13 additional cases of this distinctive neoplasm. There were seven men and six women, with a mean age of 46.5 years (range, 27-62 years). There was involvement of cervical lymph nodes (six cases), mediastinum (three cases), axilla, tonsil, spleen, and peripancreatic soft tissues (one case each). The neoplasms were grey to tan, ranging in size from 1 to 13 cm. They were formed by oval to spindle cells with eosinophilic cytoplasm growing in sheets and fascicles, with a focal storiform pattern and whorls reminiscent of those seen in meningioma. The nuclei were oval or elongated with thin nuclear membranes, inconspicuous or small eosinophilic nucleoli, and clear or dispersed chromatin. Typically, the tumor cells were intimately admixed with small lymphocytes, with a prominent perivascular cuffing. Multinucleated tumor cells were present in seven cases. Necrosis, marked cellular atypia, high mitotic rate, and/or abnormal mitoses were present in seven cases. The tumor cells were positive for CD21 (10 of 11), CD35 (10 of 11), Ki-M4p (seven of eight) Ki-FDRC1p (six of seven), vimentin (five of nine), and S100 protein (five of nine). One case stained with actin. In situ hybridization, done in six cases, did not show Epstein-Barr virus RNA sequences. Ultrastructural examination of eight cases showed long, complex, occasionally interdigitating cytoplasmic processes joined by desmosomes. The behavior of these tumors is more akin to that of a low-grade soft tissue sarcoma than a malignant lymphoma and is characterized by local recurrences and occasional metastases. Two patients died of tumor, two were alive with recurrent or metastatic disease, eight were alive with no disease, and one was lost to follow-up.

Expression of adhesion molecules and HLA-DR by macrophages and dendritic cells in aphthoid lesions of Crohn's disease: an immunocytochemical study

The phenotypes and ultrastructure of macrophages and dendritic cells in aphthoid lesions of the colon were immunocytochemically observed in patients with Crohn's disease. Biopsy specimens were endoscopically obtained from both aphthoid and advanced lesions in Crohn's disease patients. Biopsy specimens obtained from patients with infectious colitis and from normal individuals served as controls. Aphthoid lesions contained densely aggregated CD68+ macrophages, which were surrounded by numerous ID-1+ dendritic cells. In the normal controls and infectious colitis patients, however, a few scattered CD68+ macrophages and ID-1+ dendritic cells were noted beneath the surface epithelium. CD3+ lymphocytes were significantly increased in both aphthoid and advanced lesions of Crohn's disease, but the CD4/CD8 ratio was similar in all groups studied. The double immunoperoxidase staining method revealed that both CD68+ macrophages and ID-1+ dendritic cells in the aphthoid lesions simultaneously expressed ICAM-1 and HLA-DR antigens. Electronmicroscopic observation revealed that CD68+ macrophages had numerous vesicles and lysosomal granules and few projections, and that ID-1+ dendritic cells had appreciable cytoplasmic protrusions with a few vacuoles. These findings suggested that the colonic mucosa in Crohn's disease contained two types of macrophage/dendritic cells in the same lineage that expressed intercellular adhesion molecules and class-II MHC antigens. It also appeared that the aphthoid lesions of Crohn's disease featured an increase in macrophages and dendritic cells consistent with immunological activation.

Interdigitating cell sarcoma: a morphologic and immunologic study of lymph node lesions in four cases

Interdigitating cell sarcoma is an extremely rare tumor. Its presentation and histologic appearance has varied among the reported cases. In this study, the authors investigated four cases of the hematolymphoid malignancy arising within lymph nodes, which were considered to be of interdigitating cell origin. All patients presented in the 6th to 8th decade of life with peripheral lymphadenopathy, and had a relatively indolent clinical course, without bone marrow or skin involvement. Carcinomas were observed as a second neoplasm in two of four patients. Distinctive morphologic features are proliferation of histiocyte-like cells with nuclear pleomorphism and occasionally multinucleated, paracortical distribution sparing of B-cell regions, fibrosis, sinus infiltration, and a prominent eosinophil/plasma cell infiltrates. The combination of light microscopic, fine structural, and immunohistochemical features suggested that these tumors derive from interdigitating cells; these tumor cells expressed CD68 (KP1), S-100 protein and HLA-DR, but lack CD21 (1F8), desmosomes and Birbeck granules. The diagnosis of interdigitating cell sarcoma should be considered on any pleomorphic tumor with the features described in this report.

Interdigitating Reticulum Cell Sarcoma Positive immunohistochemistry for HLA-DR and two other activation antigens, CD30(Ki-1) and CD25(IL2R)

This communication reports a case of the rare interdigitating reticulum cell (IDRC) sarcoma of lymph nodes in a 46-year-old man. Extensive immunophenotypic analysis on paraffin and frozen sections revealed positivity on the neoplastic cells for protein S-100 as well as for antigens CD1, HLA-DR, CD4, CD25 (IL2R) and CD30 (Ki-1). The simultaneous positivity for the three activation antigens CD30, HLA-DR, and IL2R, a phenomenon mostly described in H and S-R cells of Hodgkin's disease, is discussed in particular.