Primary Extra-gastrointestinal Stromal Tumor of Retroperitoneum

Background Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal neoplasms of the gastrointestinal tract. More rarely neoplasms with histology and immunohistochemistry similar to GISTs may occur outside the gastrointestinal tract (omentum, mesentery and retroperitoneum) and are so-called Extra-gastrointestinal Stromal Tumors (EGISTs). EGISTs arising in the retroperitoneum are extremely rare: to date, only 58 cases have been reported in the literature. Case Report We herein report a case of a primary EGIST of the retroperitoneum surgically treated. The pre-operative radiological evaluation showed a retroperitoneal mass, placed in left paravertebral region. Results Morphological and immunohistochemical features led to a diagnosis of extra-gastrointestinal stromal tumor (intermediate-low risk form). Conclusions As a result of the rarity of reports of primary EGISTs of retroperitoneum we need to analyze the data of reported cases in order to gain a better understanding about the pathogenesis, prognosis and optimal treatment of this disease

Maffucci Syndrome: A Genome-Wide Analysis Using High Resolution Single Nucleotide Polymorphism and Expression Arrays on Four Cases

Ollier disease and Maffucci syndrome are rare, nonhereditary skeletal disorders characterized by the presence of multiple enchondromas with (Maffucci) or without (Ollier) co-existing multiple hemangiomas of soft tissue. Enchondromas can progress toward central chondrosarcomas. PTHIR mutations are found in a small subset of Ollier patients. The genetic deficit in Maffucci syndrome is unknown. Here, we report the first genome-wide analysis using Affymetrix SNP 6.0 array on Maffucci enchondromas (n = 4) and chondrosarcomas (n = 2) from four cases. Results were compared to a previously studied cohort of Ollier patients (n = 37). We found no loss of heterozygosity (LOH) or common copy number alterations shared by all enchondromas, with the exception of some copy number variations. As expected, chondrosarcomas were found to have multiple genomic imbalances. This is similar to conventional solitary and Ollier-related enchondromas and chondrosarcomas and supports the multistep genetic progression model. Expression profiling using Illumina BeadArray-v3 chip revealed that cartilaginous tumors in Maffucci patients are more similar to such tumors in Ollier patients than to sporadic cartilage tumors. Point mutations in a single gene or other copy number neutral genomic changes might play a role in enchondromagenesis. (C) 2011 Wiley-Liss, Inc.Molecular tumour pathology - and tumour genetic

Endothelium in aneurysmal bone cyst.

The surface of the large cystic spaces and dilated blood vessels in seven cases of aneurysmal bone cysts was studied. The endothelium of the blood vessels was surrounded by a layer of collagen types IV and V, and the endothelial cells contained factor VIII related antigen demonstrated by the peroxidase anti-peroxidase technique. Some blood vessels were dilated resembling small aneurysmal spaces. The visible surfaces of the aneurysmal spaces were devoid of collagen types IV and V, and of factor VIII related antigen. Ultrastructural analysis of paraffin embedded sections did not show the characteristic fine structural features of endothelium covering the aneurysmal spaces. It is concluded that the large spaces in aneurysmal bone cysts are devoid of basement membranes and endothelial cells. The absence of endothelium may explain the abundance of haemorrhages in these lesions. Immunocytochemical demonstration of endothelial antigen provides a valuable tool for the differential diagnosis between aneurysmal bone cysts and vascular tumours

A common single-nucleotide variant in T is strongly associated with chordoma

Microscopic imaging and technolog