Leiomyoblastoma is uncommon and has been known as a neoplasm of smooth muscle origin. However, with recent pragress in immunohistochemical staining techniques, many clinicopathological discrepancies have been pointed out about the origin of leiomyoblastoma. We present here a case of gastric leiomyoblastoma did not expressed desmin and neuron specific enolase, and was thought to be of unknown derivation.
Desmin ; Leiomyoma, Epithelioid* ; Muscle, Smooth ; Phosphopyruvate Hydratase

Leiomyoblastoma is uncommon and has been known as a neoplasm of smooth muscle origin. However, with recent pragress in immunohistochemical staining techniques, many clinicopathological discrepancies have been pointed out about the origin of leiomyoblastoma. We present here a case of gastric leiomyoblastoma did not expressed desmin and neuron specific enolase, and was thought to be of unknown derivation.
Desmin ; Leiomyoma, Epithelioid* ; Muscle, Smooth ; Phosphopyruvate Hydratase

Dermatofibrosarcoma protuberans (DFSP) is a slowly growing dermal spindle cell tumor and its myxoid variant, a rare type of DFSP, is characterized by extensive myxoid degeneration. We present the case of a 69-year-old woman with a multinodular reddish plaque on her trunk. Histopathologically, the tumor was located in the dermis and consisted of uniform spindle-shaped cells, showing strongly positive reaction for CD34, and negative for both S-100 and desmin. In addition to the typical storiform pattern, prominent myxoid stromal changes were demonstrated. Herein, we report an interesting case of myxoid DFSP, rarely reported in the dermatology literature.
Aged ; Dermatofibrosarcoma ; Dermatology ; Dermis ; Desmin ; Female ; Humans

The vagina is an infrequent site of primary sarcomas, which are less than 2% of all malignant vaginal neoplasm. The most common malignant mesenchymal tumor of the vagina is rhabdomyosarcoma, but leiomyosarcoma is rare type tumor of the vagina. Microscopically, spinle cells with pleomorphic nuclei and mitotic figures were frequently noted, but cross-striations were not found in the tissue. Alpha-smooth muscle actin and desmin were positive, but sarcomeric actin was negative in the tumor cells. The authors report a case of primary leiomyosarcoma of the vagina with brief literature review.
Actins ; Desmin ; Leiomyosarcoma* ; Rhabdomyosarcoma ; Sarcoma ; Vagina* ; Vaginal Neoplasms

We report on a case of angiomatoid fibrous histiocytoma located deep in subcutaneous tissue of the left shoulder in an 11-year-old boy. An ovoid firm mass was slowly increasing in size for 5 months without any pain or tenderness. The tumor was grossly multicystic, with dense fibrous capsule and it measured 7.5 x 7.5 x 4.0 cm. The locules contained hemorrhagic fluid, and the inner surface was purplish brown and trabecular. The septal solid areas were cellular, and they consisted of histiocytoid spindle cells that were arranged in a storiform or fascicular pattern. The tumor cells showed immuno-positivity for CD99, CD68 and desmin. These findings were compatible with angiomatoid fibrous histiocytoma of an uncommon location.
Child ; Desmin ; Histiocytoma, Benign Fibrous* ; Humans ; Male ; Shoulder ; Subcutaneous Tissue

Fibrous hamartoma of infancy (FHI) is an uncommon benign fibrous proliferation, usually presenting as a single nodule. A 17-month-old male patient had an asymptomatic fingertip-sized subcutaneous nodule on the right side of the back for 6 month. Histopathologic findings showed the typical feature of FHI, that is well defined intersecting fibrous trabeculae, small immature cells within loosely textured areas, and mature adipose areas in the lower dermis and subcutaneous layer. Immunohistochemically, vimentin positivity was present in both the trabecular and loosely textured areas, but desmin was not present in any components which is positive usually only in trabecular areas. The lesion was excised without recurrence. We experienced and report an uncommon case of fibrous hamartoma of infancy in a 17-month-old male patient.
Dermis ; Desmin ; Hamartoma* ; Humans ; Infant ; Male ; Recurrence ; Vimentin

Evaluation of serous effusions can include immunocytochemical stains that differentiate reactive mesothelial cell from adenocarcinoma cell. Among several positive mesothelial cell markers, we used desmin, CK5/6, WT1 and calretinin all known to have high sensitivity and specificity as selective mesothelial cell markers. We studied smears obtained with cytospin from 15 malignant and eight benign effusions. The mesothelial cells were positively stained by desmin, CK5/6, WT1 and calretinin in 60.9%, 29.1%, 26.7% and 56.5%, respectively among 8 benign and 15 malignant effusions; the adenocarcinoma cells were positively stained 6.7%, 13.3%, 1.0% and 0.0%, respectively among 15 malignant effusions. The percentage of positively stained mesothelial cells were somewhat lower for all antibodies compared to the results of previous studies. This was likely due to the differences in preparation methods and fixatives among studies. In conclusion, the use of desmin and calretinin were more valuable than CK5/6 and WT1 for distinguishing between reactive mesothelial cell and adenocarcinoma cells in serous effusion; however, choice of the proper preparation methods and fixatives are also important
Adenocarcinoma* ; Antibodies ; Calbindin 2 ; Coloring Agents ; Desmin ; Fixatives ; Sensitivity and Specificity

BACKGROUND: Glomus tumor is a benign lesion composed of vessels and glomocytes in varying proportions. Although the histologic features of glomus tumors by light microscopy are characteristic and well recognized, there is controversy as to the histogenesis and cytological characterization of the glomus cell. OBJECTIVE: The aim of the present study was to verify the histopathological origin of a glornus tumor. Method: We investigated 1 cases of glomus tumors for immunohistochemical features. RESULTS: The glomus turnor cells were negative when stained for FactorVIII-related antigen and S-100 protein. Conversely, all materials were found to be positive for actin, vimentin, NSE. Sorne exhibited an equivocal reaction for desmin and CD34, the rest were negative. CONCLUSION: These findings support the hypothesis that the glomus cell is transitional-between smooth muscle and vascular ndothelium-being essentially a modified smooth muscle cell with some endothelial cell properties.
Actins ; Desmin ; Endothelial Cells ; Glomus Tumor* ; Microscopy ; Muscle, Smooth ; Myocytes, Smooth Muscle ; S100 Proteins ; Vimentin

No abstract available.
Desmin* ; Intermediate Filament Proteins* ; Intermediate Filaments* ; Muscle, Skeletal* ; Muscular Diseases* ; Sciatic Nerve* ; Vimentin*

PURPOSE: Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumor of the gastrointestinal tract. Recent studies have revealed much of the biological and genetics underpinning GISTs. METHODS: KIT, PDGFRA, NF2 and GPHN mutations were examined by PCR-SSCP and DNA sequencing. Immunohistochemical analyses of CD117, CD34, SMA, S-100 and desmin were performed in 11 GISTs cases, and each tumor classified as being either very low, low, intermediate or high risk. RESULTS: Mutation in exon 11 of KIT was identified in 6 of the 11 GISTs, but mutations in exon 9, 13 and 17 of KIT were not detected. Three cases lacking KIT mutations showed PDGFRA mutations. No NF2 mutations were detected. GPHN gene mutation in exon 1 was identified in one case, which showed a simple point mutation in exon 11 of KIT. In a correlation between the mutation types and risk of aggressive behavior, four tumors involved multiple ( >2 codons) KIT mutations and one showed a point mutation of KIT plus a GPHN mutation were high risk, but one tumor with a point mutation of KIT showed a low risk. Three tumors having a PDGFRA mutation were of intermediate or very low risk. CONCLUSION: Mutations at exon 9, 13 or 17 of KIT and a NF2 mutation are considered rare in sporadic GIST. KIT and PDGFRA mutations appeared to be alternatives. A GPHN mutation occurring with a KIT mutation may be a secondary change in the pathogenesis of GIST, as the KIT mutation is a major event in GIST. KIT mutant GIST may have a poorer prognosis than PDGFRA mutant GIST.
Desmin ; Exons ; Gastrointestinal Stromal Tumors* ; Gastrointestinal Tract ; Genetics ; Point Mutation ; Prognosis ; Sequence Analysis, DNA