1/8. HMB-45/melan-A and smooth muscle actin-positive clear-cell epithelioid tumor arising in the ligamentum teres hepatis: additional example of clear cell 'sugar' tumors.HMB-45-positive clear-cell epithelioid tumor arising in the ligamentum teres hepatis of a 13-year-old Japanese girl is described. The well-defined tumor was completely removed and measured 9 x 7 x 6 cm. Cut sections showed a tan-white, homogeneous appearances with no hemorrhage or necrosis. The tumor was composed of nests or sheets of polygonal or oval-shaped cells rich in clear or finely granular cytoplasm. Capillary network was well developed, and sinusoid vessels were often seen with occasional perivascular hyalinization. There was moderate nuclear atypia but mitotic figures were absent. periodic acid-Schiff stain showed a large amount of glycogen digested by diastase. Immunohistochemical stains for smooth muscle actin, Melan-A, and HMB-45 were positive in most of the tumor cells. Stains for vimentin, muscle actin, and HAM56 were focally positive, whereas stains for desmin, cytokeratin, epithelial membrane antigen, S-100, CD34, CD68, CD99, neurofilament proteins, and estrogen/progesterone receptors were negative. Ultrastructurally, the cytoplasm contained a considerable number of mitochondria, monoparticipate or membrane-bound glycogen, and longitudinally oriented thin filaments with focal condensations and subplasmalemmal densities. The histopathology of the present case, originally interpreted as epithelioid leiomyoma, was consistent with clear cell "sugar" tumors. The present case may indicate ubiquitous distribution of clear cell "sugar tumors" of which histogenesis remains unknown but is presumed to be of perivascular epithelioid cell origin.- - - - - - - - - - ranking = 1keywords = vessel (Clic here for more details about this article) |
2/8. Benign clear cell tumor of the lung.A 49-year-old woman presented with a solitary pulmonary nodule in the right lung. The tumor was well circumscribed and showed a reddish brown cut surface. It showed a diffuse growth pattern of polygonal cells with clear abundant cytoplasm and distinct cell border around thin-walled vascular spaces and sinusoid-type vessels. Based on morphological findings, the patient was diagnosed as having benign clear cell tumor of the lung. silver impregnation and PAM stains showed fine reticular fibers continuously surrounding the vessels and individual neoplastic clear cells. Strong immunostaining for type IV collagen was observed surrounding all the individual clear cells. A few clear cells were positive for HMB-45 and NCAM 123C3 (CD56). Electron microscopically, clear cells had numerous membrane-bound glycogen granules and a large amount of non-membrane-bound glycogen. The neoplastic cells were surrounded by external lamina and cytoplasmic processes. The neoplastic clear cells showed morphologic features seen in pericytes, melanocytic cells, and neuroendocrine cells.- - - - - - - - - - ranking = 2keywords = vessel (Clic here for more details about this article) |
3/8. spleen-preserving total pancreatectomy with conservation of the spleen vessels:: operative technique and possible indications.Conventional distal pancreatectomy (cDP) and total pancreatectomy (cTP) also involve removal of the spleen. The spleen, however, is an important organ in the immunologic defense of the host and is worthy of preservation if this can be safely achieved.We performed a spleen-preserving total pancreatectomy (SPTP), with good results, in a Caucasian woman, 66-year-old, affected by pancreatic metastases of renal clear cell carcinoma.This is the first report of a SPTP for pancreatic metastases to our knowledge, and we therefore wish to describe the surgical technique and to suggest the possible indications for this new technique.- - - - - - - - - - ranking = 4keywords = vessel (Clic here for more details about this article) |
4/8. Salvage lung metastasectomy by video-assisted transmanubrial approach.Surgical treatment of lung metastasis has become common, but extended pulmonary metastasectomy is not accepted worldwide. We report a case of huge apical pulmonary metastasis of renal cancer with involvement of the subclavian vessels associated to two additional lesions of the lower lobe. All lung deposits were successfully removed through a combination of a transmanubrial cervicothoracic approach for the apical lesion and a videothoracoscopic technique for the nodules of the lower lobe.- - - - - - - - - - ranking = 1keywords = vessel (Clic here for more details about this article) |
5/8. Cutaneous clear cell myomelanocytic tumour: a new member of the growing family of perivascular epithelioid cell tumours (PEComas). Clinicopathological and immunohistochemical analysis of seven cases.AIMS: To analyse seven cases of cutaneous myomelanocytic tumour histologically and immunohistochemically. Perivascular epithelioid cell tumours (so-called PEComas) are rare and recently delineated neoplasms occurring in the lung, kidney, pancreas, uterus, falciform ligament, vulva, heart, prostate and soft tissues. PEComas are characterized by a perivascular location of neoplastic cells showing a broad spectrum of epithelioid and spindled cells with clear, and granular pale eosinophilic cytoplasm, and a variable expression of melanocytic and muscle markers, whereas S100 protein and cytokeratins are usually absent. methods AND RESULTS: We report seven cases of cutaneous myomelanocytic tumour arising on the lower (six cases) and upper (one case) extremities of female adults (age range 30-66 years). In all cases an ill-defined dermal lesion with extension into subcutaneous tissue was noted. The neoplasms contained numerous blood vessels with a lace-like pattern and slightly thickened vessel walls, and were composed of perivascular epithelioid cells containing clear or focally granular pale eosinophilic cytoplasm and round vesicular nuclei with small, sometimes slightly enlarged nucleoli. Increased proliferative activity and tumour necrosis were not seen. Immunohistochemically, tumour cells stained positively for HMB-45, microphthalmia transcription factor, and NKIC3 in all cases, whereas perivascular expression of alpha-smooth muscle actin and focal positivity for desmin were noted in one case each only. Two out of four cases tested stained focally positive for calponin. No expression of S100 protein and pancytokeratin was present. Despite incomplete/marginal excision in three cases none of the neoplasms has recurred locally so far. CONCLUSIONS: With the presented series of cutaneous myomelanocytic tumours the clinicopathological spectrum of PEComas is expanded.- - - - - - - - - - ranking = 2keywords = vessel (Clic here for more details about this article) |
6/8. Hepatic resection of giant metastatic tumor from clear cell carcinoma of the ovary.All cancer patients, particularly those treated for colorectal cancer, should be monitored for the presence of liver metastases, but liver metastases from ovarian clear cell carcinoma are quite rare. We report a patient subjected to extended left hepatectomy due to a giant metastasis 5 years after surgical treatment for an ovarian neoplasm that was histopathologically diagnosed as clear cell carcinoma. A 58-year-old woman had undergone hysterectomy and bilateral salpingo-oophorectomy due to ovarian cancer (stage Ic). Four years and 8 months after the operation, a computed tomography (CT) scan demonstrated a giant tumor in the left lobe of the liver. The tumor compressed the inferior vena cava (IVC), but it was not clear whether it invaded the vessel. She received chemotherapy for 4 months; however, the tumor did not decrease in size. She was subsequently referred to our institution and was submitted to operation after it was confirmed that there were no distant metastases. After being subjected to an extended left hepatectomy and cholecystectomy, the patient recovered from the surgery without any complications. She has been carefully followed for 17 months and has presented no evidence of recurrence.- - - - - - - - - - ranking = 1keywords = vessel (Clic here for more details about this article) |
7/8. Benign clear (sugar) cell tumor of the lung with CD1a expression.Reported herein is a case of benign clear cell tumor of the lung in a 60-year-old man. Chest X-ray and CT examination revealed an abnormal nodule with homogenous density and a clear margin in the lower lobe of the left lung. The resected tumor was 13 mm in size, well-circumscribed and was graysh-white on cut surface. Histological examination showed a diffuse growth pattern of polygonal tumor cells with indented and pleomorphic nuclei, and clear abundant cytoplasm with a distinct cell border surrounded by thin-walled vascular spaces and sinusoid-type vessels. The clear cytoplasm contained numerous glycogen granules as demonstrated by PAS staining. In the present case there was focal immunoreactivity for S-100 protein, HMB-45, neuron-specific enolase, cathepsin b and melan A, which are consistent with reported immunohistochemical staining patterns of benign clear cell tumor. Based on these findings, the tumor was diagnosed as a benign clear cell tumor of the lung. Although most clear cell tumors are considered to belong to the family of neoplasms with perivascular epithelioid cell differentiation (PEComas), histogenesis of benign clear cell tumor of the lung has remained unclear. This first report of CD1a expression in this tumor might provide a new insight into its histogenesis and diagnosis.- - - - - - - - - - ranking = 1keywords = vessel (Clic here for more details about this article) |
8/8. Clear cell tumor of the lung: an immunohistochemical and ultrastructural study supporting a pericytic differentiation.Clear cell tumor ("sugar tumor") of the lung is a rare benign lesion with unclear histogenesis. It is composed of large cells with a clear cytoplasm rich in glycogen, blended with an abundant network of sinusoid-type vessels. We report two cases of sugar tumor, one of these lacking clearly demonstrable glycogen storage. In both, the tumor cells lacked keratin expression and were positive for vimentin and HMB 45, an antibody recognizing perivascular or myoid cell proliferation such as lymphangioleiomyomatosis and angiomyolipoma. The tumor cells were also immunoreactive for an endothelial cell marker, CD 34, but negative for factor viii or smooth muscle actin. Intercellular deposition of basal-like material was immunostained with Type IV collagen. At ultrastructural examination of one of these cases, tumor cells showing features of pericytes or poorly differentiated perivascular leiomyocytes encased in basement material were observed in close association with endothelial cells; their cytoplasm contained numerous membrane-bound glycogen and pinocytic vesicles. We conclude that on the basis of immunohistochemical and ultrastructural phenotype, sugar tumor presents pericytic features and that glycogen storage is not a constant feature of these benign tumors.- - - - - - - - - - ranking = 1keywords = vessel (Clic here for more details about this article) |