1/18. recurrence of a neurenteric cyst with malignant transformation in the foramen magnum after total resection. Case report.A 53-year-old man presented with recurrence of a neurenteric cyst with malignant transformation in the foramen magnum 3.5 years after total resection of the original tumor had been reported. For 2 years following the initial surgery, the patient had been in good condition, but then underwent ventriculoperitoneal shunt placement for intracranial hypertension. At the time there was no evidence of recurrence of the tumor on magnetic resonance (MR) images. One and one-half years later, he presented with headache and anorexia. A massive recurrent tumor was identified on MR images. The tumor was severely adhesive to the brainstem, cranial nerves, and vessels, allowing only partial resection. Histological examination of tumor specimens obtained during the first and second craniotomies indicated a malignant change from a typical neurenteric cyst with a one-layer epithelium in the first specimen to an adenocarcinoma with papillary proliferation in the second. The results of various immunohistochemical studies of the first specimen were typical of those of a neurenteric cyst. The second specimen displayed stronger staining of carbohydrate 19-9 and carcinoembryonic antigens than the initial specimen. The percentage of ki-67 antigen (MIB-1)-positive cells increased from 0% in the first specimen to 6.7% in the second. To the authors' knowledge this is the first case in which malignant transformation has been demonstrated after total resection of a neurenteric cyst in the foramen magnum.- - - - - - - - - - ranking = 1keywords = vessel (Clic here for more details about this article) |
2/18. Malignant transformation of renal angiomyolipoma: a case report.We report a case of renal angiomyolipoma (AML) with malignant transformation. A 28-year-old woman developed large bilateral renal masses 5 months before admission to our hospital. She was diagnosed with tuberous sclerosis when she was 4 years old. Total nephrectomy of the left kidney was performed, but she died during the operation. Although the focal region of the resected tumor had the appearance of a classic AML, most of the lesion showed a diffuse proliferation of atypical epithelioid cells resembling that in renal cell carcinoma. The epithelioid cells had extremely pleomorphic and hyperchromatic nuclei with frequent mitotic figures, including atypical forms. Immunohistochemical analysis revealed that the atypical epithelioid cells and the typical AML lesions were both positive for HMB-45 but that the former were negative for epithelial and myogenic markers. The smooth muscle cells and thick-walled vessels were focally positive for muscle-specific actins. Furthermore, the atypical epithelioid cells were immunoreactive for p53, whereas the foci of the typical AML were negative. Examination of the microdissected paraffin-embedded tissues revealed p53 mutations in the malignant epithelioid areas in AML but not in the renal parenchyma or typical AML areas. In this case it is proposed that p53 mutation may play an important role in malignant transformation of renal AML.- - - - - - - - - - ranking = 1keywords = vessel (Clic here for more details about this article) |
3/18. Desmoplastic primitive neuroectodermal tumor with divergent differentiation. Broadening the spectrum of desmoplastic infantile neuroepithelial tumors.We report an unusual large, multicystic, posterior fossa neuroepithelial neoplasm involving the cerebellum, brain-stem, and quadrigeminal cistern of a 9-month-old girl. The neoplasm consisted of variably sized, sharply demarcated nests of small cells with a high nuclear-cytoplasmic ratio and moderately basophilic nuclei, embedded in a desmoplastic, immature-appearing, mesenchymal stroma. The nests contained mitoses but none were seen in the stroma. glial fibrillary acidic protein (GFAP), neurofilament protein, synaptophysin, and cytokeratin (AE-1) were expressed in the nests. Mesenchymal cells were negative for neural markers but positive for vimentin and desmin. The neoplasm was interpreted as a mixed mesenchymal and primitive neuroectodermal tumor (PNET) with histologic features reminiscent of a recently described intraabdominal desmoplastic small cell tumor. The tumor responded poorly to chemotherapy and a second operation was performed 1 year later. The second specimen bore no resemblance to the original and consisted of epithelial-like nests and clusters of neoplastic cells frequently interrupted by sinusoidal vessels. Tumor cells had medium-sized vesicular nuclei with small nucleoli, and a granular cytoplasm. Occasional less cellular islands of neuropil-like tissue contained larger cells having eccentric, vesicular nuclei with prominent nucleoli and abundant pink cytoplasm. Mitoses were not conspicuous. Many cells expressed synaptophysin, neurofilament protein, and GFAP. Neurofilament protein was strongly positive in the larger, neuron-like cells and synaptophysin stained the neuropil-like areas strongly but was less prominent in the neuronal perikarya. Unexpectedly, the neuropil-like areas expressed epithelial membrane antigen, whereas the neuronal cells were negative for chromogranin a. The peculiar histologic picture, combination of phenotypic markers, and remarkable biologic behavior of this unusual tumor defies classification according to existing nomenclature and exemplifies the broad range of phenotypes expressed by primitive neuro-epithelial neoplasms.- - - - - - - - - - ranking = 1keywords = vessel (Clic here for more details about this article) |
4/18. Epithelial differentiation in medulloblastoma: comparison with other embryonal tumors of neuroectodermal origin.Three cases of medulloblastoma characterized by epithelial differentiation are described in patients 6-months-, 1-month- and 8-years-old. Histologically, tumors from the two infant patients showed a perivascular arrangement without apparent radiated cytoplasmic processes from the vessels. Tumor cells displayed round and/or pleomorphic vesicular nuclei and a more abundant eosinophilic cytoplasm than that found in classic medulloblastoma. Neither Homer-Wright rosettes nor ependymal or ependymoblastic rosettes were noted in these tumors. The tumor in the 8-year-old patient exhibited a classic medulloblastoma component intermingled with abundant eosinophilic cytoplasm forming a tubular structure. Immunohistochemically, tumor cells in all cases were positive for cytokeratin, synaptophysin, and vimentin. In the third case involving the 8-year-old patient, epithelial tumor cells were positive for cytokeratin, whereas classic medulloblastoma components were negative for cytokeratin. Positive staining for melanoma-specific antigen was seen only in the third case, where strong reactivity of tumor cells formed a tubulus. However, the classic medulloblastoma component was negative for melanoma-specific antigen. Ultrastructurally, basal laminae were observed around tumor cells in the 6-month-old patient. These morphological and immunohistochemical features suggest that medulloblastoma with epithelial differentiation is a rare but distinct variant of medulloblastoma, and that some of these tumors should show differentiation in ocular pigment epithelium.- - - - - - - - - - ranking = 1keywords = vessel (Clic here for more details about this article) |
5/18. AA-type amyloidosis associated with non-Hodgkin's lymphoma: a case report.Amyloid-associated protein (AA)-type systemic amyloidosis has been referred to as secondary amyloidosis because it is secondary to an associated inflammatory condition. It is extremely rare in patients with non-Hodgkin's lymphoma (NHL). Here we report an autopsy case of follicular small cleaved cell lymphoma with focal large B-cell lymphoma transformation in association with systemic AA-type amyloidosis. Formalin-fixed, paraffin-embedded tissues from autopsy and the patient's previous surgical specimen were studied by congo red stain; electron microscopy; and immunostaining with antibodies against AA protein, P component, and kappa and lambda light chains. There was a marked AA amyloid deposition in the glomeruli of both kidneys, the retroperitoneal lymphoma mass, the blood vessels, the adrenal glands, and the adipose tissues. The patient's previous surgical specimens were negative for amyloid. We propose that this patient's systemic AA-type amyloidosis developed along the course of his NHL.- - - - - - - - - - ranking = 1keywords = vessel (Clic here for more details about this article) |
6/18. Intravascular large B-cell lymphoma colonizing cutaneous hemangiomas.Intravascular large B-cell lymphoma is a malignant neoplasm characterized by the proliferation of large B cells (rarely of T lymphocytes) confined within the blood vessels. Although the disease can be limited to the skin, involvement of other organs is common. We report a case of intravascular large B-cell lymphoma colonizing the vessels of preexisting cutaneous cherry hemangiomas.- - - - - - - - - - ranking = 2keywords = vessel (Clic here for more details about this article) |
7/18. Malignant transformation of a spinal cord ganglioglioma--case report and review of the literature.Gangliogliomas are tumors of mixed glial and neuronal phenotype that usually have a benign clinical course. Rare cases display anaplastic features at the time of first presentation or progress to anaplastic gliomas over extended times. We report on a ganglioglioma of the spinal cord that recurred as a malignant glioma one and a half years after resection. The initial neoplasm was composed of a mixture of well-differentiated ganglionic and astrocytic cells. The recurrent tumor was an anaplastic small-cell glioma. The sole unusual aspect in the initial neoplasm was an abundance of small vessels with calcified walls, which mimicked a vascular malformation.- - - - - - - - - - ranking = 1keywords = vessel (Clic here for more details about this article) |
8/18. hemangiopericytoma of the infratemporal fossa: progression toward malignancy in a 30-year history.hemangiopericytoma is a rare vascular tumor first described by Stout and Murray in 1942 and characterized by a proliferation of Zimmermann's pericytes, smooth muscle cells arranged around blood vessels. This tumor presents as a slowly enlarging painless mass. diagnosis with certainty is often a difficult one because of the close likeness with other spindle cell tumors; it requires the help of immunohistochemical techniques and sometimes ultrastructural techniques. Only 15% of hemangiopericytomas are localized in the cervicofacial region; in particular, occurrence in the infratemporal fossa is an exceptional occurrence. In this article, we report an unusual case of recidivate hemangiopericytoma of the infratemporal fossa that has progressively assumed features of malignancy over 30 years. The hemangiopericytoma relapse potentiality is elevated, even when the histologic characteristics of the tumor indicate a low aggressivity, and therefore every hemangiopericytoma must be considered to have malignant potential. In conclusion, the unpredictable behavior of hemangiopericytoma requires a radical primary treatment to avoid the risk of relapses that always are frequent and aggressive.- - - - - - - - - - ranking = 1keywords = vessel (Clic here for more details about this article) |
9/18. carcinosarcoma of monoclonal origin arising in a dermoid cyst of ovary: a case report.BACKGROUND: Transformation of a cystic benign teratoma of the ovary into a "carcinosarcoma" has very rarely been reported and its histogenetic origin is still debated. CASE PRESENTATION: A case of carcinosarcoma arising from a dermoid cyst is reported. The tumor showed cystic areas delimited by normal squamous epithelium, with transitional areas through dysplastic epithelium to "in situ" and infiltrating squamous cell carcinoma (SCC). The sarcomatous component showed compact tissue composed of round cells concentrically arranged around small vessels, spindle, and pleomorphic cells with a high nuclear-cytoplasmic ratio. Positive staining for vimentin, alpha smooth muscle actin and CD10, as well as P53 and P63, was found in the sarcomatous component and in some atypical basal cells of the squamous epithelium, which also showed the usual epithelial markers. CONCLUSION: To the best of our knowledge, this is the first case of carcinosarcoma arising from a dermoid cyst in which a histogenetic origin from totipotent stem cells, located in the basal squamous layer, is supported by immunohistochemical findings.- - - - - - - - - - ranking = 1keywords = vessel (Clic here for more details about this article) |
10/18. Epithelioid hemangioendothelioma of the spinal cord: Description of a case with cytogenetic analysis.A case of epithelioid hemangioendothelioma of the cauda equina is reported. The patient presented with rapidly worsening low back pain. magnetic resonance imaging revealed a sharply demarcated intradural lumbar lesion. A bluish-red lesion, attached to the filum terminale, was removed. The patient is alive without evidence of recurrence 18 months after surgery. The tumor was composed of variously sized vessels lined by epithelioid endothelial cells with clear cytoplasm and centrally located, moderately atypical nuclei. These cells were immunoreactive for CD31 and factor viii antibodies. cytogenetic analysis disclosed two clones: 44-45X, - Y [cp3]/46XY[11]. Epithelioid hemangioendothelioma may arise in several sites, the most common being soft tissues. It is a borderline tumor that may recur, may metastasize, and rarely causes death. The present case appears to be the first example of epithelioid hemangioendothelioma of the spinal cord.- - - - - - - - - - ranking = 1keywords = vessel (Clic here for more details about this article) |
| | Next -> |