This study was designed to reexamine the healing process of expanded polytetrafluoroethylene (EPTFE) grafts with standard porosity (30 microm) and high porosity (60 microm) in portal vein replacement, and to evaluate the effect of an omentum wrap, which has certain functions that promote healing, on graft healing. These grafts, either wrapped by the omentum or not, were placed as portal vein replacements in 24 mongrel dogs. After 1 month, the grafts were retrieved and examined for patency, thrombus-free areas, thickness of the pseudointima, and the total number of cells growing into the graft wall. There were no statistical differences in the patency rates. The high-porosity grafts had a significantly larger thrombus-free area, a thicker pseudointima, and a larger growth of cells than the standard-porosity grafts. The omentum wrap significantly increased the thrombus-free area and stimulated a larger growth of cells in both grafts. The high-porosity grafts plus omentum demonstrated a thrombus-free area of 82.2% vs 27.3% in the standard-porosity grafts. In addition, the migration of fibroblasts and macrophages was most evident in the high-porosity grafts wrapped by the omentum. In conclusion, graft healing enhancement was observed in the high-porosity EPTFE grafts wrapped by the omentum. It is thus suggested that transmural cellular migration plays an important role in the process of graft healing.

Primary liposarcoma of the mediastinum is rare, but cases of recurrence have been reported in the English literature. We successfully resected a recurrent pericardial liposarcoma, detected 5 years after the initial resection of a liposarcoma of the anterior mediastinum invading the pericardium. Routine follow-up computed tomography showed the recurrence and suggested invasion of the pericardial cavity, which was supported by the findings of transesophageal ultrasonography. As cine-magnetic resonance imaging suggested that the tumor was resectable, an operation was performed. Histopathology confirmed the diagnosis of recurrent liposarcoma and showed clear surgical margins.

We examined the patency and healing of a high-porosity expanded polytetrafluoroethylene (ePTFE) graft implanted as an interposition graft in the thoracic inferior vena cava (IVC) and wrapped in an omental pedicle flap. High-porosity ePTFE grafts of 60 microns fibril length, with an internal diameter of 10 mm and a length of 4 cm, were implanted in 12 mongrel dogs. In 6 dogs, the grafts were wrapped in omental pedicle flap, and in the remaining 6 the grafts were unwrapped. The animals were killed 4 weeks after the replacement and the grafts were removed for examination. Patency of the graft in both groups was 100%; however, the thrombus-free area in the omentum-wrapped group was significantly larger (P < 0.05) than that in the unwrapped group. Light microscopy revealed the marked infiltration of cells and capillaries within the graft interstices in the omentum-wrapped group. These findings suggest that encapsulation of the high-porosity ePTFE graft is promoted by an omental pedicle flap.

Background: Pancreatoduodenectomy with resection of the portal vein or superior mesenteric vein confluence has been safely performed in patients with pancreatic head cancer associated with infiltration of the portal vein or superior mesenteric vein. In recent years, left-sided portal hypertension, a late postoperative complication, has received focus owing to increased long-term survival with advances in chemotherapy. Left-sided hypertension may sometimes cause fatal gastrointestinal bleeding because of the rupture of gastrointestinal varices. Here, we present a case of colonic varices caused by left-sided portal hypertension after pancreatoduodenectomy with portal vein resection. Case presentation: A 69-year-old man diagnosed with pancreatic head cancer was referred to our department for surgery after undergoing chemotherapy with nine courses of gemcitabine and nab-paclitaxel. Computed tomography showed a mass 25 mm in diameter and in contact with the portal vein. He had undergone subtotal stomachpreserving pancreatoduodenectomy with portal vein resection. Four centimeters of the portal vein had been resected, and end-to-end anastomosis was performed without splenic vein reconstruction. We had to completely resect the right colic vein, accessary right colic vein, and middle colic vein due to tumor invasion. The pathological diagnosis was ypT3, ypN1a, ypM0, and ypStageIIB, and he was administered TS-1 as postoperative adjuvant chemotherapy. Seven months after therapeutic radical surgery, he presented with melena with progressive anemia. Computed tomography revealed transverse colonic varices. He was offered interventional radiology. Trans-splenic arterial splenic venography showed that transverse colonic varices had developed as collateral circulation of the splenic vein and inferior mesenteric vein system. An embolic substance was injected into the transverse colonic varices, which halted the progression of the anemia caused by melena. Fifteen months after therapeutic radical surgery, local recurrence of the tumor occurred; he died 28 months after the surgery. Conclusions: When subtotal stomach-preserving pancreatoduodenectomy with portal vein resection is performed without splenic vein reconstruction, colonic varices may result from left-sided portal hypertension. Interventional radiology is an effective treatment for gastrointestinal bleeding due to colonic varices, but it is important to be observant for colonic necrosis and new varices.

Wedge resection of the portal bifurcation is easier and simpler than using a venous patch or performing segmental resection.

Both esophageal rupture and esophageal cancer are life-threatening diseases. We report a case of esophageal cancer that occurred after esophageal rupture was treated with thoracoscopic and laparoscopic surgery. A 76-year-old man presented with vomiting followed by epigastric pain and was diagnosed with spontaneous esophageal rupture. Laparoscopic and thoracoscopic surgery were performed. Primary closure was completed with a fundic patch, and thoracic lavage was performed. Ten months later, his condition was diagnosed as squamous cell carcinoma of the abdominal esophagus. He underwent thoracoscopic esophageal resection in the prone position, and a gastric conduit was created laparoscopically. The pathological finding was superficial esophageal carcinoma without lymph node metastasis. The patient's postoperative course was uneventful, and there was no recurrence at 21 months of follow-up.

Involvement in the subcarinal node might be a prognostic factor for SCLC.

This report describes a case of secondary pneumothorax caused by a radiographically occult lung metastasis from parapharyngeal synovial sarcoma, a relatively rare tumor known to be highly metastatic to the lung. Although chest X-ray and thoracic computed tomography scan failed to detect the metastatic nodule in the right lung, the surgically resected specimen proved to be a 3-mm lung metastasis. To our knowledge, only eight cases of lung metastases from synovial sarcoma causing pneumothorax have ever been reported. In most of these cases, the lung metastases were detected by radiographical examinations. However, in this patient, the metastatic lesion was not detected during examination. It is speculated that secondary pneumothorax caused by synovial sarcoma may occur during the early stages of lung metastasis. Therefore, if pneumothorax occurs in a patient with a synovial sarcoma, the possibility of lung metastasis should be carefully considered, even if it is undetectable on radiological examinations.