[Solitary fibrous tumor/hemangiopericytoma].

Solitary fibrous tumor(SFT)/hemangiopericytoma(HPC)is a rare mesenchymal tumor with propensity for recurrence and metastasis. Although SFT and HPC were initially considered to be distinct entities, the identification of NAB2-STAT6 fusion as a definitive molecular alteration in both tumors has led to their integration into one disease entity, for both meningeal and non-meningeal lesions. This fusion leads to a nuclear relocation of the STAT6 protein and is detectable with immunohistochemistry. STAT6 immunohistochemistry has been shown to have excellent sensitivity and specificity for histological diagnosis. Although these discoveries have improved the diagnosis of SFT/HPC, the association of the NAB2-STAT6 fusion status with phenotype and prognosis remains unclear, and accurate prognostic factors have not been established. This comprehensive review provides current knowledge on the clinical, histological, and molecular characteristics of SFT/HPC.

Mallory-Weiss tear during gastric endoscopic submucosal dissection.

A 78-year-old woman was referred to our department for treatment of an early gastric cancer. Esophagogastroduodenoscopy (EGD) demonstrated a flat elevated lesion and a polypoid lesion on the greater curvature of the antrum. Histological analysis of, endoscopic biopsy samples taken from these lesions revealed an adenocarcinoma and a hyperplastic polyp, respectively. ESD was conducted for removal of the lesions. Carbon dioxide (CO(2)) instead of room air was used for insufflation, and the patient was adequately sedated without struggling or vomiting during the treatment. No significant bleeding from the lesion was observed during ESD, but fresh blood was identified endoscopically. Surprisingly, a Mallory-Weiss tear with active bleeding was detected on the lesser curvature of the gastric corpus. A total of eight hemoclips were applied for hemostasis. Both lesions were completely removed en bloc, and no bleeding or perforation developed after ESD. Histologically, the first lesion was a papillary carcinoma limited to the mucosal layer and without lymphovascular invasion or involvement of the surgical margins, while the second lesion was a benign hyperplastic polyp.