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

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

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

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

Most submucosal tumors of the stomach are of mesenchymal origin. Gastric schwannoma, which is a subset of mesenchymal tumors, is a rare tumor taking origin from Schwann's cells. A 61-year-old woman whose endoscopy showed a well circumscribed submucosal mass measuring 2.5 cm on the midbody of the stomach. Endosonographically, the tumor was well circumscribed, low echoic submucosal mass with cystic lesion in the 4th layer of the gastric wall. The patient underwent wedge resection. Microscopically, the cells were made up of irregular fasciculating bundles of spindle cells featured with benign nuclear atypia and peripheral lymphoid cell cuffing, involving muscularis propria. Immunohistochemical staining showed positivity for S-100 protein and the neuron-specific enolase, but were negative to CD 34, desmin and smooth muscle actin. From these findings, this tumor was diagnosed as a schwannoma.
Actins ; Desmin ; Endoscopy ; Female ; Humans ; Lymphocytes ; Middle Aged ; Muscle, Smooth ; Neurilemmoma* ; Phosphopyruvate Hydratase ; S100 Proteins ; Stomach

Angiomyofibroblastoma is a recently described mesenchymal tumor characterized by unique morphologic features, a propensity to arise in the vulva, and a non-aggressive beni-gn biologic behavior. It is typically well circumscribed and superficially located tumor and its cellularity is variable with hypercellular and hypocellular areas composed of bland-looking, pump stromal cells showing the immunophenotype of vimentin-/desmin - positive, and muscle specific actin(MSA)-/alpha-smooth muscle actin(ASMA) - negative. Spindle or plasm-acytoid cells are the characteristic cell types of most tumors. It is similar to an aggressive pelvic angiomyxoma in histology. Because of histologic similarity and differences in the clinical course and treatment, distinction from aggressive angiomyxoma was needed. It rep-resents new type in the expanding spectrum of tumors of which myofibroblasts constitute an integral component. We experienced a case of angiomyofibroblastoma of the vulva occuring in a 42 years old woman. The lesion was relatively well encapsulated mass(3 X 1.5 X 0.9 cm in dimension), showing intimate admixture of hypercellular and hypocellular area. The tumor contained prominent, somewhat ectatic vessels surrounded by smooth muscle cells, some of which blend or fan out from the muscular walls of the vessels. The margin was relatively free from tumor cells. At immunohistochemical stain, vimentin and desmin was diffuse and weak positive, smooth muscle actin was very a few and weak positive in tumor cells.
Actins ; Adult ; Desmin ; Female ; Humans ; Muscle, Smooth ; Myocytes, Smooth Muscle ; Myofibroblasts ; Myxoma ; Stromal Cells ; Vimentin ; Vulva*

Lipomatous variant of angiomyofibroblastoma is a rare tumor of the vulva. Most of cases are usually premenopausal and present with a slowly growing mass without pain. A 46-year-old woman presented with a swelling of the left labium major. The lesion was thought to be a Batholin's gland cyst or a lipoma preoperatively and a local excision was performed. The tumor was well demarcated and rubbery. On microscopic examination, the alternating hypercellular and edematous hypocellular component with abundant vessels was noted. A large amount of adipose tissue was scattered in the lesion. Stromal cells were positive for vimentin, estrogen receptor, and progesterone receptor and negative for desmin antibody immunostaining. The local excision was enough for complete treatment. No recurrence was noted for 7 months after surgery.
Adipose Tissue ; Desmin ; Estrogens ; Female ; Humans ; Lipoma ; Middle Aged ; Receptors, Progesterone ; Recurrence ; Stromal Cells ; Vimentin ; Vulva