PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Neoplasms, Muscle Tissue”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 541 records · Page 30Linked to original sources
PubMed1999

Inflammatory (pseudosarcomatous) myofibroblastic tumor of the urinary bladder causing acute abdominal pain.

Inflammatory myofibroblastic tumor is a reactive proliferation of myofibroblasts that rarely involves the urinary bladder. The cause of inflammatory myofibroblastic tumor is unknown but may represent an initial reactive process to an infectious agent or trauma that transforms into neoplastic growth. Cases reported in children, however, often lack any preexisting bladder pathology. The authors present a case in a young child that presented as acute abdominal pain. In general, these tumors follow a benign clinical course after resection, although close monitoring is essential given the rarity of this bladder lesion.

Abdomen, Acute↗
PubMed1979

Granular cell tumor of the tongue.

The granular cell tumor has been and still is a debatable lesion in several aspects. The etiology and pathogenesis are still unknown. Granular cell tumors may occur everywhere in the body, but the oral cavity is a favorite location. The majority of the oral lesions are found in the dorsum and the borders of the anterior two-thirds of the tongue. Seven patients with a granular cell tumor of the tongue are described. The clinical and microscopic findings have been discussed. In all cases an excisional biopsy had been aimed at. In spite of incomplete excision in six out of the seven cases, local recurrences were noticed in only one patient. In one patient "metastatic" occurrence of granular cell tumors was noticed.

Adult↗
PubMed1999

Myofibroblastic tumours: neoplasias with divergent behaviour. Ultrastructural and flow cytometric analysis.

Myofibroblasts are spindle cells having ultrastructural features in common with smooth muscle cells and fibroblasts. In the last few years, tumours have been described in which myofibroblasts represent not only a reactive mechanism but also a true neoplastic component. They constitute new nosologic entities which might be termed "myofibroblastic tumours". Tumours with benign and, rarely, malignant behaviour are reported to belong to this group of lesions. Recently, a third tumour type with borderline biological course, named "inflammatory myofibroblastic tumour" (IMT), has been identified, a condition that has been regarded as a benign and reactive disorder for a long time. Only in recent reports has been demonstrated that, in spite of an apparently benign morphological pattern, some cases of IMT have a malignant course. In this connection, DNA analysis by flow cytometry is a valuable diagnostic tool, because it allows identification of the ploidy status, a procedure that is often useful for predicting the nature and the biological behaviour of the lesion. In this study, 11 cases of myofibroblastic tumours were examined retrospectively by evaluating clinicopathological features and DNA ploidy status by flow cytometry. The diagnosis of myofibroblastic tumour was confirmed by performing histology, immunohistochemistry, and electron microscopy in all patients. In detail, these 11 cases were composed of 1 benign myofibroblastoma, 1 myofibrosarcoma and 9 IMTs. Among these myofibroblastic tumours, all those with local recurrence or distant metastases (one myofibrosarcoma and three IMT) showed an aneuploid cell population demonstrable by flow cytometric analysis, whereas the other cases with benign course (one benign myofibroblastoma and six IMT) exhibited an euploid DNA content. These data suggest the following: a) Besides the rare myofibroblastomas and myofibrosarcomas, IMTs represent a larger group of lesions with potentially different biological and clinical course. b) DNA flow cytometric analysis is a reliable tool that support histopathological examination in characterizing those cases of IMT that, though being malignant, mimic benign lesions. Consequently, it establishes the basis for a different therapeutic approach according to the euploid or aneuploid DNA content.

Adult↗
PubMed1983

Granular cell myoblastoma in the tongue of a dog: a case report.

A granular cell myoblastoma was found in the dorsal side of the tongue of a 9-year-old female mongrel Pinscher. Macroscopically the tumour was white, well circumscribed, and 1 1/2 cm in diameter. Microscopically the tumour cells were arranged in small compact nests or cords with delicate, poorly vascularized collagen bundles in between. Acinar structures were found, also a few mitotic figures were present. Cytoplasmic granules showed a positive periodic acid Schiff reaction. Ultrastructural features included indented nuclei and small-sized vesicular cytoplasmic granules. The histogenesis of the neoplasm remains uncertain.

Animals↗
PubMed1986

Locally aggressive granular cell tumor causing priapism of the crus of the clitoris. A light and ultrastructural study, with observations concerning the pathogenesis of fibrosis of the corpus cavernosum in priapism.

A case of focal priapism of the clitoris caused by a microscopic granular cell tumor (GCT) is described. This neoplasm is considered locally aggressive because it invades the lumens of peripheral cavernous sinuses of the crus of the clitoris. Caverns adjacent to those invaded by tumor exhibit stasis, telangiectasia, and necrosis of the smooth muscle of the trabecular wall. These alterations lead to telescoping collapse and compression of the cavernous spaces and culminate in fibrosis. Ultrastructurally, replicated basal lamina is found surrounding clusters of granular cells. We suspect that the multilayered lamina, in addition to being produced by tumor cells, is derived from the trabecular endothelium surrounding the caverns invaded by the GCT. The replication of the basal lamina may be provoked by cycles of injury and repair to these vessels caused by repeated episodes of prolonged vascular stasis. A peculiar large vein with perforating branches was observed in the center of the cavernous spaces of the crus. This vein is not found in normal crura and, therefore, represents a morphologic adaptation created to drain the cavernous spaces.

Adult↗
PubMed1991

Primitive polypoid granular-cell tumor and other cutaneous granular-cell neoplasms of apparent nonneural origin.

Most cutaneous and noncutaneous granular-cell tumors are currently thought to be of Schwann-cell derivation. We present seven unusual cutaneous granular-cell lesions in which Schwann-cell origin can be excluded or is inapparent. Four of these lesions are of a previously undescribed type, and, unlike conventional granular-cell tumors of the skin, show a polypoid configuration, numerous mitoses, cytologic atypia, and a primitive immunophenotype. We propose the term "primitive polypoid granular-cell tumor" for these lesions. One occurred in a child, and three in adults. There have been no metastases to date, with follow-up periods of 2, 4, 4, and 16 years, respectively, although one tumor recurred locally. Additional cases and longer follow-up may be required to rule out the possibility that primitive polypoid granular-cell tumor is a low-grade malignancy. Two other granular-cell lesions represent variants of leiomyosarcoma, one of which widely metastasized. The last case is a granular-cell form of nodular basal-cell carcinoma. Cutaneous granular-cell neoplasms can show varying differentiation and behavior. Pathologists should not equate the occurrence of cytoplasmic granularity in a cutaneous neoplasm with the diagnosis of granular-cell schwannoma.

Adult↗
PubMed1992

Angiomyofibroblastoma of the vulva. A benign neoplasm distinct from aggressive angiomyxoma.

Aggressive angiomyxoma of pelvic soft parts is a rare lesion with a high risk of recurrence. We report 10 cases of angiomyofibroblastoma, a hitherto uncharacterized benign tumor of the vulva histologically mimicking aggressive angiomyxoma. All patients had a vulval mass, often clinically diagnosed as a Bartholin's cyst. There was no recurrence after excision. The tumors were well circumscribed, measuring 0.5-12 cm in maximum dimension. They were characterized by alternating hypercellular and hypocellular edematous zones in which abundant blood vessels (predominantly of the capillary type) were irregularly distributed. Spindled, plump spindled, and oval stromal cells were aggregated around the blood vessels, sometimes forming solid compact foci, or were loosely dispersed in the hypocellular areas. Their nuclei were bland, but rare ones were enlarged and hyperchromatic in four cases. Some cells had abundant eosinophilic hyaline cytoplasm and eccentrically placed nuclei. Mitotic figures were absent or very sparse. Scattered throughout were thin, wavy strands or thick bundles of collagen. Mast cells were readily seen in eight cases. Immunohistochemically, the stromal cells were reactive for vimentin and desmin, but not cytokeratin, muscle-specific actin, alpha-smooth muscle actin, or S-100 protein. Ultrastructural studies showed well-developed rough endoplasmic reticulum, Golgi apparatus, abundant intermediate filaments, and pinocytotic vesicles in the stromal cells. Angiomyofibroblastoma can be distinguished from aggressive angiomyxoma by its circumscribed borders, much higher cellularity, more numerous blood vessels (which lack prominent hyalinization), frequent presence of plump stromal cells, minimal stromal mucin, and rarity of erythrocyte extravasation.

Adult↗
PubMed1997

Angiomyofibroblastoma of the vulva with sarcomatous transformation ("angiomyofibrosarcoma").

We report on a locally recurrent vulvar tumor in an 80-year-old woman that we believe represents the first example of malignant transformation of an angiomyofibroblastoma. The tumor was predominantly a typical angiomyofibroblastoma, composed of epithelioid or oval cells with eosinophilic cytoplasm that tended to cluster in small groups and around blood vessels. These areas merged imperceptibly with a high-grade sarcoma that resembled a myxoid malignant fibrous histiocytoma. The tumor cells in the benign areas were diffusely immunoreactive for vimentin; many cells were positive for smooth muscle actin, and focal positivity for muscle actin and desmin was observed. The tumor cells in the sarcomatous areas were diffusely positive for vimentin, but negative for smooth muscle actin, muscle actin, and desmin. No staining for keratin, S-100 protein, or CD34 was noted. Ultrastructural examination of the sarcomatous area showed that the cells had the features of fibroblasts. All previously reported cases of angiomyofibroblastoma have exhibited banal histologic features and have behaved in a benign fashion. This case shows that these tumors may rarely be associated with a malignant component, and the designation "angiomyofibrosarcoma" may be appropriate in such cases.

Actins↗
PubMed1991

Vulvar granular cell tumors with pseudocarcinomatous hyperplasia: a comparative analysis with well-differentiated squamous carcinoma.

The clinical and pathological findings in 10 cases of vulvar granular cell tumor are reviewed. Nine patients presented with solitary, grossly circumscribed, subcutaneous or submucosal nodules and one with synchronous bilateral labial nodules; two exhibited surface epithelial ulceration. Striking pseudocarcinomatous hyperplasia of the overlying squamous epithelium was noted in five of the 10 cases, leading to a misdiagnosis of invasive squamous carcinoma on superficial biopsy in one case. In contrast to previously published data, it was found that pseudocarcinomatous hyperplasia contained numerous mitotic figures, squamous pearls, mildly atypical nuclei, focally prominent nucleoli, and focal single cell infiltration; follicular infundibula were not preferentially involved. Excluding the presence of the underlying granular cell tumor, these features rendered the hyperplastic proliferation nearly indistinguishable from infiltrative squamous carcinoma. Marked squamous cell atypia, although not always present in biopsies of well-differentiated squamous carcinoma, was the only distinguishing histologic feature not found in pseudocarcinomatous hyperplasia. Although vulvar granular cell tumor is an unusual neoplasm, it should be considered in the differential diagnosis of an apparently infiltrative squamous lesion of the vulva when the base of the lesion is not present in the biopsy specimen. This is particularly true of tumors with a nodular, radially symmetric gross appearance.

Adult↗
PubMed1996

Neural variant of fetal rhabdomyoma and naevoid basal cell carcinoma syndrome.

A 15-year-old boy with the characteristic features of the naevoid basal cell carcinoma syndrome presented with a retroperitoneal mass. The tumour showed morphological features of a still ill-defined variant of fetal rhabdomyoma, characterized by well-differentiated nerve fibres admixed with immature striated muscle cells, similar to neuromuscular choristoma. Four cases of fetal rhabdomyoma and naevoid basal cell carcinoma syndrome have been previously reported. The behaviour of this tumour has been benign, although a complete excision was impossible due to its close relation with abdominal vascular trunks.

Adolescent↗