1/3. Diffuse type of giant-cell tumor of tendon sheath: an ultrastructural study of two cases with cytogenetic support.Two cases of the diffuse type of giant-cell tumor of the tendon sheath (GCTTS) are described. Both tumors arose in the vicinity of large joints of the lower extremity, showing similar clinical and radiological features. Histologically, a proliferation of polygonal mononuclear cells was seen, together with osteoclastlike giant cells, foam cells, and siderophages. The tumors were poorly delineated, displaying an infiltrative pattern into the neighboring soft tissues. Immunohistochemically, strong expression of vimentin, neuron-specific enolase, A1-antitrypsin, and CD68 was found in both mono- and multinucleated tumor cells. At the ultrastructural level, mononuclear cells revealed a diverse morphology, displaying features of histiocytelike and fibroblastlike cells, with the former being more numerous. Scarce neurosecretorylike granules, made up of electrondense membrane-bound material, were found in the cytoplasm of the mononuclear cells. cytogenetic analysis of one case shows the presence of a clonal population with 47 chromosomes and two different translocations, t(2;3) and der(8) t(8;12). Present findings provide further support regarding the neoplasic nature of this tumoral entity.- - - - - - - - - - ranking = 1keywords = t-cell (Clic here for more details about this article) |
2/3. Giant-cell tumor of bone, stage II, displaying translocation t(12;19)(q13;q13).A new case of giant-cell tumour (GCT) of bone with benign histological features, clinical stage II, has been reviewed with immunohistochemistry and electron microscopy. After short-term tissue culture the karyotype, using G-banding techniques, presented a consistent translocation t(12;19)(q13;q13). Nude mice xenografts of the tumour were unsuccessful after 6 months of follow-up. Presence of such chromosomal rearrangement may be related to locally aggressive, histologically benign giant-cell tumors of bone.- - - - - - - - - - ranking = 1.2keywords = t-cell (Clic here for more details about this article) |
3/3. Translocation, t(17;22)(q22;q13), in dermatofibrosarcoma protuberans: a new tumor-associated chromosome rearrangement.A translocation, t(17;22)(q22;q13), was identified in two cases of dermatofibrosarcoma protuberans (DP). They bring to four the number of DP cases characterized by an identical t(17;22)(q22;q13), which can be considered as a new tumor-associated chromosome rearrangement. To date, this translocation has been found only in DP and its juvenile form, giant-cell fibroblastoma. This finding has two major consequences. First, it casts light on the development and significance in DP of ring chromosomes which consistently harbor sequences derived from chromosomes 17 and 22. Second, the identification of this new chromosome marker, and eventually of the underlying molecular rearrangement, should help to classify DP, a soft-tissue tumor of still uncertain cell origin. In addition, it could be used to differentiate DP from truly benign or malignant entities, in order that this tumor of intermediate malignancy could be adequately managed.- - - - - - - - - - ranking = 0.2keywords = t-cell (Clic here for more details about this article) |