Toyonori Tsuzuki

Pyogenic granuloma of the stomach successfully treated by endoscopic resection after transarterial embolization of the feeding artery

Pyogenic granulomas represent the aquisition of vasodilative granulation tissue in the skin or mucosa. They are extremely rare in the alimentary tract, other than in the oral cavity. Here, we report a case of pyogenic granuloma arising from the gastric mucosa. An 82-year-old man was admitted to our hospital because of melena of more than 3 months, duration. Esophagogastroduodenoscopy (EGD) revealed a 30-mm-diameter semipedunculated lesion with an irregular surface in the fundus of the stomach. During hospitalization, the patient’s anemia worsened due to loss of blood from the lesion, with the level of hemoglobin declining to 6 g/dl, and a blood transfusion was required. Because radiological and endoscopic findings indicated the lesion was hypervascular, transarterial embolization of the nutritional artery of the lesion was performed before endoscopic resection of the lesion. One week after the embolotherapy, endoscopic mucosal resection was performed, without any complications, such as massive bleeding. Histological studies of the resected specimen revealed many capillaries of various sizes, lined with plump endothelial cells, and accompanied by acute and chronic inflammatory infiltrates. On the basis of these observations, the lesion was diagnosed as a pyogenic granuloma. One year later, the patient was asymptomatic and there was no evidence of tumor recurrence on follow-up EGD.

A Case of Pacreatic Endocrine Carcinoma That Invaded to the Main Pancreatic Duct with Difficulty in Diagnosis to Invasive Ductal Cancer

症例は30歳の男性で, 心窩部痛にて入院した. CT上, 膵体尾部に42×39mmの充実性腫瘍を認めた. Endoscopic retrograde pancreatography, magnetic resonance cholangiopancreatographyでは, 主膵管が完全途絶していた. 超音波内視鏡検査では内部不均一で周囲がlow, 腹部血管造影では腫瘍濃染像は認めず, 脾動脈にencasementを認めた. 確定診断のため, 超音波内視鏡検査下穿刺細胞診を行いendocrine tumorと診断された. 手術は膵体尾部脾合併切除術を施行した. 病理診断は低分化型膵内分泌細胞癌であり, CD56強陽性, synaptophysin強陽性, chromogranin A一部弱陽性であった. 主膵管は強度に浸潤を受け, 腫瘍細胞に置き換わり, 脾動静脈にも腫瘍浸潤を認めた. 術後14か月現在, 再発徴候は認めていない. 本症は30歳と若年発症であり, 内分泌細胞癌でありながら主膵管浸潤浸潤を認めたまれな症例である. 膵内分泌腫瘍と診断し, 主膵管閉塞を認めた場合には悪性を疑う必要がある.

A Case of Gastrointestinal Stromal Tumor with Internal Tandem Duplication in the 3 -Terminal of the KIT Juxtamembrane Domain

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors originating from the gastrointestinal tract and are responsible for approximately 80% of all the gastrointestinal mesenchymal neoplasms. Most GISTs show immunologically positive for both CD34 and KIT (CD117), which is a characteristic also of the interstitial cells of Cajal (ICC), the gastrointestinal pacemaker cells. Therefore, GISTs are now considered to originate from the ICC or be progenitors that differentiate toward a pacemaker cells phenotype (1–4). KIT is a type III receptor tyrosine kinase encoded by the protooncogene c-kit, and its ligand is stem-cell factor. Activating mutations of the KIT gene—which lead to ligand-independent activation of the tyrosine kinase of KIT—play a fundamental role in the development of these tumors (5, 6). It has been reported that most mutations consist of in-frame deletions or a single amino acid substitution within exon 11 that codes for the juxtamembrane domain (6), and rarely in exon 9 (extracellular region) as well as exon 13 (first part of the split kinase domain) (5). Diagnosis of malignant GISTs has been problematic among clinicians and pathologists. Traditionally, mitotic index, tumor size, and tumor location are considered to be the key predictive factors. KIT-activating mutations are now also proposed as a predictive factors of prognosis (5, 7–9). Recently, internal tandem duplication (ITD) in