A case of pancreatic PEComa with prominent inflammatory cell infiltration: the inflammatory subtype is a distinct histologic group of PEComa.

BACKGROUND: PEComa is a mesenchymal tumor that can occur in various organs including the uterus and soft tissues. PEComas are composed of perivascular epithelioid cells, and angiomyolipoma (AML), clear cell sugar tumor (CCST), and lymphangiomyomatosis (LAM) are considered lesions of the same lineage as tumors of the PEComa family. Histologically, a common PEComa shows solid or sheet-like proliferation of epithelioid cells. This is accompanied by an increase in the number of dilated blood vessels. Here, we report a case of pancreatic PEComa with marked inflammatory cell infiltration. CASE PRESENTATION: A 74-year-old male patient underwent an appendectomy for acute appendicitis. Postoperative computed tomography and magnetic resonance imaging revealed a 30 × 25 mm non-contrast-enhanced circular lesion in the tail of the pancreas. The imaging findings were consistent with a malignant tumor, and distal pancreatectomy was performed. Histologically, most area of the lesion was infiltrated with inflammatory cells. A few epithelioid cells with large, round nuclei, distinct nucleoli, and eosinophilic granular cytoplasm were observed. Spindle-shaped tumor cells were observed. Delicate and dilated blood vessels were observed around the tumor cells. Immunohistochemically, the atypical cells were positive for αSMA, Melan A, HMB-45, and TFE3. The cytological characteristics of the tumor cells and the results of immunohistochemical staining led to a diagnosis of pancreatic PEComa. CONCLUSIONS: A histological variant known as the inflammatory subtype has been defined for hepatic AML. A small number of tumor cells present with marked inflammatory cell infiltration, accounting for more than half of the lesions, and an inflammatory myofibroblastic tumor-like appearance. To our knowledge, this is the first report of pancreatic PEComa with severe inflammation. PEComa is also a generic term for tumors derived from perivascular epithelioid cells, such as AML, CCST, and LAM. Thus, this case is considered an inflammatory subtype of PEComa. It has a distinctive morphology that is not typical of PEComa. This histological phenotype should be widely recognized.

Gastric cancer simultaneously complicated with extrahepatic bile duct metastasis and portal vein tumor thrombus: a case report.

BACKGROUND: Gastric cancer metastatic to the extrahepatic bile duct or accompanied by portal vein tumor thrombus (PVTT) is rare. To our knowledge, there have been no cases complicated with both of these factors. CASE PRESENTATION: A 72-year-old man presented with icterus and melena. A biochemical blood test showed abnormal values for hepatobiliary enzymes and a tumor marker, and abdominal computed tomography scan revealed wall thickening of the lower bile duct with intra- and extra-hepatic bile duct dilatation and PVTT. A biopsy of the lower bile duct during endoscopic retrograde cholangiopancreatography demonstrated a moderately differentiated tubular adenocarcinoma. Moreover, gastroduodenoscopy showed a type 3 tumor at the lesser curvature of the gastric antrum, and an endoscopic biopsy demonstrated a moderately differentiated tubular adenocarcinoma. We diagnosed concomitant gastric cancer and distal bile duct accompanied by PVTT, and pancreatoduodenectomy with combined resection of the portal vein was performed. The resected specimen revealed a tumor in the lesser curvature of the gastric antrum and circumferential wall thickening in the lower bile duct. In pathological findings, infiltration of a moderately differentiated tubular adenocarcinoma from the mucosal layer to the subserosal layer of the stomach was observed. In contrast, a moderately differentiated tubular adenocarcinoma demonstrating the same histological type as the gastric cancer had spread not to the mucosal layer but mainly to the fibromuscular layer of the lower bile duct. Immunohistochemical staining showed identical patterns between gastric cancer and the bile duct tumor: negativity for cytokeratin 7 (CK7), and positivity for CK19 and 20. Therefore, the final diagnosis was extrahepatic bile duct metastasis from gastric cancer with PVTT. Unfortunately, multiple liver metastases occurred in the early postoperative period and chemotherapy was conducted, but the patient died 12 months after the surgery. CONCLUSIONS: In the diagnosis of extrahepatic bile duct metastasis, immunohistochemical staining of gastric cancer and the bile duct tumor was essential and helpful as decisive evidence.

[A Case of Gastric Cancer with Pulmonary Carcinomatous Lymphangitis and Disseminated Carcinomatosis of the Bone Marrow Responding to S-1 plus Cisplatin Chemotherapy].

A 63-year-old man was admitted to a hospital owing to shortness of breath. He was diagnosed as having gastric cancer with pulmonary carcinomatous lymphangitis(PCL)and disseminated carcinomatosis of the bone marrow(DCBM). Regarding tumor markers, carcinoembryonic antigen(CEA)and carbohydrate antigen 19-9(CA19-9)levels increased to 332 ng/ mL and 921 U/mL, respectively. Since the disease was also accompanied by disseminated intravascular coagulation(DIC), S- 1 plus cisplatin chemotherapy was started immediately(S-1 120 mg/body administered for 21 days and cisplatin 60 mg/m2 administered on day 8, 35 days for a course). Approximately 2 weeks after the initiation of chemotherapy, the patient's respiratory symptoms improved, and he recovered from DIC. After 2 chemotherapy courses, tumor marker levels decreased (CEA 9.3 ng/mL and CA19-9 314 U/mL), and the patient continued to receive chemotherapy without the deterioration of his physical condition for 5 months. However, he experienced fatigue after 4 courses, because of the progression of gastric cancer. Although the regimen was changed to ramucirumab plus paclitaxel chemotherapy, the patient died 8 months after the initiation of chemotherapy. An accumulation of cases is needed to establish treatment strategies for gastric cancer with PCL and/or DCBM.

Surgical resection for small bowel obstruction due to right ovarian metastasis after ileocecal resection for cecal cancer: A case report.

Although oophorectomy for ovarian metastasis from colorectal cancer is encouraged to improve the prognosis, that is also performed to relieve the symptom such as abdominal distention. We report a surgical case of intestinal obstruction due to ovarian metastasis after ileocecal resection for cecal cancer diagnosed at 77 years old.

Reg3α and Reg3ß Expressions Followed by JAK2/STAT3 Activation Play a Pivotal Role in the Acceleration of Liver Hypertrophy in a Rat ALPPS Model.

To explore the underlying mechanism of rapid liver hypertrophy by liver partition in associating liver partition and portal vein ligation for staged hepatectomy (ALPPS), liver partition at different sites was investigated. Increased inflammatory cytokines owing to the liver partition have been reportedly responsible. If this were true, rapid liver hypertrophy should be achieved regardless of where the liver was split. A male Sprague-Dawley rat model was created, in which a liver split was placed inside the portal vein ligated lobe (PiLL), in addition to the ALPPS and portal vein ligation (PVL) models. Liver regeneration rate, inflammatory cytokine levels, activation status of the Janus kinase 2/signal transducer and activator of transcription 3 (JAK2/STAT3) pathway and expressions of regenerating islet-derived (Reg)3α and Reg3ß were investigated. The liver regeneration rate was significantly higher in the ALPPS group than in the PiLL group, whereas inflammatory cytokine levels were nearly equal. Additional volume increase in ALPPS group over PVL and PiLL groups was JAK2/STAT3-dependent. Reg3α and Reg3ß expressions were observed only in the ALPPS group. An increase in inflammatory cytokines was not enough to describe the mechanism of rapid liver hypertrophy in ALPPS. Expressions of Reg3α and Reg3ß could play an important role in conjunction with an activation of the JAK2/STAT3 pathway.

Hepatic Stellate Cells Play a Functional Role in Exacerbating Ischemia-Reperfusion Injury in Rat Liver.

PURPOSE: The involvement of hepatic stellate cells (HSCs) with ischemia-reperfusion (I/R) injury in rat liver was examined using gliotoxin, which is known to induce HSC apoptosis. METHODS: Male Sprague-Dawley rats were used. HSC was represented by a glial fibrillary acidic protein (GFAP)-positive cell. Liver ischemia was produced by cross-clamping the hepatoduodenal ligament. The degree of I/R injury was evaluated by a release of aminotransferases. Sinusoidal diameter and sinusoidal perfusion rates were examined using intravital fluorescence microscopy. RESULTS: Gliotoxin significantly decreased the number of GFAP-positive cells 48 h after dosing (2.50 ± 0.19% [mean ± SD] in the nontreated group vs. 1.91 ± 0.46% in the gliotoxin-treated group). Liver damage was significantly suppressed by the pretreatment with gliotoxin. Sinusoidal diameters in zone 3 were wider in the gliotoxin group (10.25 ± 0.35 µm) than in the nontreated group (8.21 ± 0.50 µm). The sinusoidal perfusion rate was maintained as well in the gliotoxin group as in normal livers, even after I/R. CONCLUSIONS: Pretreatment with gliotoxin significantly reduced the number of HSCs in the liver and further suppressed liver injury following I/R. It is strongly suggested that HSCs play a functional role in exacerbating the degree of I/R injury of the liver.