Subcutaneous fibrosarcoma with low malignancy in a pig.
Explore the source record for details and available documents.
SEARCH · Search PubMed
Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Explore the source record for details and available documents.
The free calcium concentrations in nucleus ([Ca2+]n) and cytoplasm ([Ca2+]c) of cultured DDT1MF-2 smooth muscle cells were estimated using the fluorescent dye indo-1 and laser confocal microscopy. The alkaloid staurosporine mainly increased [Ca2+]c during the initial minutes of stimulation and the nucleocytoplasmic gradient was maintained. Thereafter [Ca2+]n increased further while [Ca2+]c decreased, resulting after 10 min in a reversion of the nucleocytoplasmic gradient. Staurosporine increased the Ca2+ influx but also released intracellular Ca2+. In Ca(2+)-free solution no inversion of the nucleocytoplasmic gradient was seen in most cells. Ca2+ increased more rapidly in the area of the perinuclear sarcoplasmic reticulum (SR) than in the central cytoplasm. This is suggestive of the release of Ca2+ from this region. Ca2+ concentration remained also enhanced near the plasmalemma during this time period. This might indicate that the efflux mechanism is also affected. It is unlikely that these changes are due to inhibition of protein kinase C, since phorbol esters are ineffective and since downregulation by prolonged incubation with phorbol 12-myristate 13-acetate only affected the time periods required to attain the described [Ca2+]c and [Ca2+]n peaks. The slow time course of the staurosporine effects allowed demonstration of the spatiotemporal Ca2+ gradients between the nucleus and the cytoplasm and also inside the cytosol. The different time course of the increases in [Ca2+]c and [Ca2+]n suggests that two different Ca2+ mobilization events are present. The occurrence of an inversion of the nucleocytoplasmic gradient whereby [Ca2+]n increased while [Ca2+]c values decreased indicates that the increase in [Ca2+]n might result partially from release sites inside the nucleus.(ABSTRACT TRUNCATED AT 250 WORDS)
Explore the source record for details and available documents.
BACKGROUND: Ossifying fibromyxoid tumor (OFMT) of soft parts is a rare, recently defined, fibroosseous neoplasm, generally regarded as clinically benign; however, one-third of cases recur locally, and several malignant examples have been reported. Fine needle aspiration (FNA) cytology of the tumor is rarely described in the literature. We provide the first cytomorphologic study of the malignant variant. CASE: A 70-year-old man presented with an intramuscular mass in the right buttock. Computed tomography revealed ossification within the mass and multiple pulmonary nodules. FNA biopsy showed round and polygonal to spindled tumor cells, arrayed singly, cordlike or in small aggregates, with scattered dense stromal fragments and a slightly myxoid background. The nuclei showed significant pleomorphism accompanied by coarse chromatin with clumping, irregular contours, and one to two distinct nucleoli. The tumor cells were recognizable as sarcoma, with no evidence of high grade malignancy. The tumor was totally excised, histopathologically confirmed as the malignant variant of OFMT of soft parts, and immunohistochemically and ultrastracturally analyzed as of neural origin. CONCLUSION: The FNA specimen revealed that the cytomorphology was consistent with the histologic features of the malignant variant of OFMT, but several characteristic histologic parameters, such as multilobular proliferation and peripherally placed mature, bony trabeculae, were not reflected in the aspirates. Although FNA cytologic findings may be of limited diagnostic utility in OFMT, radiographic evidence of calcification/ossification suggests that OFMT should be subjected to differential diagnosis with fine needle aspiration biopsy of soft tissue tumors. Additional studies will be required for further clarification.
Explore the source record for details and available documents.
Benign and malignant neural and neuroendocrine tumors of the larynx are uncommon enough that knowledge about them is sparse, coming from single case reports and literature reviews. We have reviewed the clinical behavior, pathologic findings, treatment, and outcome in 42 patients seen at one institution from 1907 to 1986. In some cases, electron microscopy or immunocytochemistry, or both, may be needed to reach the correct diagnosis. Treatment is largely determined by the histopathologic features, size, and location of the tumor. The most common sites are the supraglottic region and posterior larynx. Most tumors are treated by conservation surgery, including transoral excision; however, some are aggressive and require larger surgical procedures, including wide-field laryngectomy and complete neck dissection.
Explore the source record for details and available documents.
This 7-year-old boy presented with a 2-week history of headache, nausea, vomiting, anorexia, lethargy, and unsteadiness of gait. Brain magnetic resonance imaging (MRI) revealed a cystic mass within the vermis of the cerebellum. A suboccipital craniectomy was performed to remove a tumor that contained primitive neuroectodermal cells with florid skeletal muscle differentiation. Immunohistochemical studies and electron microscopy confirmed the presence of both a primitive neuroectodermal component and rhabdomyoblastic differentiation, consistent with the diagnosis of medullomyoblastoma. This exceedingly rare tumor of the cerebellar vermis of children is characterized by two components: primitive neuroectodermal tumor cells and skeletal muscle. Although the histogenesis remains uncertain, advances in immunohistochemistry and electron microscopy suggest the origin of this tumor from a multipotential stem cell precursor.
Inflammatory leiomyosarcoma, a rare entity first described in 1995, has been characterized by smooth muscle differentiation, a near-haploid karyotype, and a surprisingly good prognosis. The morphology is similar to that of conventional leiomyosarcoma admixed with a chronic inflammatory infiltrate. Thus far, only 15 cases have been reported in the English language literature. We report the clinical and pathological features of 3 additional cases of inflammatory leiomyosarcoma. Two women (ages 64 and 25, respectively) and 1 man (age 32) presented with a thigh, ovary, and lung mass, respectively. Inflammatory symptoms, such as anorexia, fever, night sweats, abdominal pain, and diarrhea, coincided with the thigh and ovarian primaries. Immunohistochemical studies revealed diffuse positivity for desmin and poor expression for other smooth muscle and skeletal muscle markers (muscle-specific actin [0/3], alpha-smooth muscle actin 1/3 [focal], calponin [1/3], caldesmon [0/3], and myogenin [0/3]). CD68 was diffusely positive in both the histiocytes and spindle cell component in all cases. Ultrastructural evaluation of 1 case (lung primary) lacked definitive smooth muscle differentiation. Cytogenetic analysis in 1 of 2 cases that were karyotyped, identified a near-haploid karyotype, which has been reported in other cases of inflammatory leiomyosarcoma. The other case showed 2 clonal populations of cells with interstitial deletions of the short arm of chromosome 8 and the long arm of chromosome 9, respectively. The case without cytogenetic data was intimately associated with an ovarian mature teratoma. These data also suggest that inflammatory leiomyosarcoma may lack smooth muscle differentiation, characterized by diffuse immunoreactivity for desmin but lack of immunoreactivity for alpha-smooth muscle actin, calponin, and caldesmon. In addition, 2 of the 3 cases developed distant metastases to the lungs, which suggests that these lesions may have a worse prognosis than previously believed.
We report two cases of schwannoma displaying marked cystic changes; one in the temporalis muscle and one in the submandibular space. The first patient, a 44-year-old male, presented after complaining of a swelling rapidly increasing in size in the left temporal region. Computed tomography (CT) indicated a low-density area surrounded by soft tissue. Magnetic resonance imaging (MRI) revealed signal hypointensity on T1 weighted imaging and strong signal hyperintensity on T2 weighted imaging. The extirpated tumour specimen measured 58 mm x 58 mm x 30 mm. Histopathological examination identified schwannoma, comprising spindle cell proliferation in a palisading pattern with obvious cystic changes. The second case involved a 46-year-old female who presented with swelling of the right submandibular region. Panoramic radiography and lateral oblique mandible projection, which were used together with conventional sialography of the submandibular gland, revealed the so-called "ball in hand" appearance of the submandibular gland, and contrast-enhanced CT identified a lesion of 30 mm diameter with a well-defined annular margin and homogeneous low-density near the tumour centre. Benign pleomorphic adenoma was suspected, but histopathological examination identified schwannoma, predominantly comprising Antoni B type tissue.
Nineteen cases with major resections of the head and neck were treated with laryngeal suspension and cricopharyngeal myotomy in an attempt to allow swallowing function postoperatively and avoid a total laryngectomy. Sixteen cases were available for evaluation. Eight cases (50%) were able to eat by mouth, 15 patients (94%) had a normal airway and 14 patients (87%) had intelligible speech.
Since the concept of myocutaneous flap reconstruction of the head and neck region was introduced it has opened a new approach to surgical management in this area. This flap not only reduced the number of operations as compared to "staged procedure", but also reduced the costs of medical care. We are, however, experiencing significant failures as the applications of this flap are extended. This paper reviews our experience with myocutaneous flaps in 15 partial and total failures. An evaluation of these failures reveals that most occurred 1 1/2 to 3 weeks after reconstruction. The factors predisposing to failure seem related more to technical errors rather than to general factors. Diabetes, peripheral vascular disease, malnutrition and low hemoglobin, and low blood pressure were not major contributors to the failures in our series. Local factors predisposing to failure of myocutaneous flaps can be divided into two large categories--arterial failure and venous failure. In our series of unsuccessful myocutaneous flaps, the major factors appeared to be venous stasis leading to arterial insufficiency. All failures had developed after the initial critical period of flap survival (7-10 days). The following techniques showed an especially high rate of failure: 1. SCM--myocutaneous flap to resurface floor of mouth. 2. Tubed pectoralis myocutaneous flap to reconstruct pharynx and esophagus. 3. Flaps developed with very narrow vascular pedicles. Individual cases representing delayed failure are presented.
Intramuscular myxoma of the head and neck is a rare lesion with only six cases documented in the literature. The tumor demonstrates a benign clinical course without a tendency to recur and is occasionally associated with fibrous dysplasia. It thus deserves to be considered in a separate class from other soft tissue myxomas. The seventh case of a head and neck intramuscular myxoma is presented and the clinical, pathological, and CT characteristics of this tumor are reviewed.
Intramuscular desmoid tumors (musculoaponeurotic fibromatosis) were discovered in two young adult horses. The tumor in one horse was in the lateral cervical musculature, and that in the second horse occurred in the pectoral musculature. Histopathologic features were similar in both horses and included proliferation of fibroblasts and cells expressing muscle actin (myofibroblasts), with extensive dissecting fibrosis within muscle. These features are similar to those of desmoid tumors in humans, particularly those also known as musculoaponeurotic fibromatosis. Dissection of these lesions revealed a single central (horse No. 1) or multiple central (horse No. 2) fluid-filled cavities with associated sterile inflammation. The presence of these cavities supports the hypothesis that equine desmoid tumors are traumatic in origin, possibly occurring at sites of injections or bursal rupture. Surgical excision of the tumor in horse No. 1 was apparently curative, but the extent of the tumor in horse No. 2 precluded surgical excision.
Explore the source record for details and available documents.
A 14-year-old girl presented with a diffuse venous hemangioma of the right temporalis muscle. The muscle had become swollen, thinning the underlying zygomatic and temporal bones. Magnetic resonance (MR) imaging demonstrated a diffuse isointense area containing high intensity foci on the T1-weighted images, and a serpiginous high intensity pattern on the T2-weighted images. A biopsy specimen revealed irregularly dilated veins in the fibrous stroma of the muscle. Diffuse abnormal signals on MR images may be a pathognomonic feature of intramuscular venous hemangiomas.
Explore the source record for details and available documents.
Explore the source record for details and available documents.