Traumatic sigmoid colon rupture due to breast cancer metastasis: a case report.

The metastasis of breast cancer to the gastrointestinal tract is rare. Herein, we presented the case of an 85-year-old woman who had a history of invasive lobular carcinoma and experienced complete colon rupture due to relatively low-energy trauma. The patient underwent bilateral total mastectomy and axillary dissection following preoperative chemotherapy 6 years ago. She had a local recurrence 2 years after the surgery and underwent chemotherapy. Subsequently, the cancer metastasized to the thoracolumbar area and retroperitoneum. In addition, the patient fell from a height of 30 cm while hanging laundry and her abdomen hit a hose reel. Emergency surgery was performed, and the entire circumference of the sigmoid colon was ruptured. The ruptured colon lesion was resected, and the stump was closed. A double-barrel transverse colostomy was created as it was impossible to lift the stump up to the abdominal wall. Histopathological examination revealed the invasive lobular carcinoma metastasis and a linitis plastica-like change of the colon wall, which probably consequently weakened. In addition, minimal trauma can damage the gastrointestinal tract that had invasive lobular carcinoma metastasis.

Malignant peripheral nerve sheath tumour of the oesophagus: a case report.

BACKGROUND: Malignant peripheral nerve sheath tumour (MPNST) is a very rare disease, and its pathogenesis is unknown. There are few reports of MPNST of the oesophagus. We report a case of an MPNST that was diagnosed and resected. CASE PRESENTATION: A 30-year-old female presented with dysphagia. She had been aware of the dysphagia approximately 6 months before presentation. The chest X-ray showed shadows in the right mediastinum. Barium fluoroscopy revealed a semicircular raised lesion in the lower oesophagus. Upper gastrointestinal endoscopy revealed a type 1 oesophageal tumour centred on the posterior wall 26-35 cm from the incisors. The surface was ulcerated, and the tumour was exposed. The affected area showed no iodine uptake. The EUS showed an isoechoic mass. The CT scan showed a mass of 71 × 61 × 55 mm in the beginning of the lower oesophagus with low density mass and swelling of the right recurrent nerve lymph node to 12 mm. On FDG-PET, the tumour showed an SUVmax of 11.05, and no abnormal accumulation was found in lymph nodes or other organs. The MRI showed a hyperintense mass on the T2WI, which had prolonged contrast enhancement, and no findings of invasion into surrounding tissue were found. The patient underwent right thoracotomy and open thoracic oesophagectomy. The affected lymph node was tumour negative by rapid pathological diagnosis during the operation. Histologically, spindle cells with different-sized nuclei were mixed throughout the tissue. Some regions showed nuclear polymorphism or a storiform pattern, and locally, there were approximately 7 mitoses/10 HPFs. The margin was relatively clear, but spindle-shaped tumour cells infiltrated the surrounding interstitium and basal myoepithelium, and the patient was diagnosed with MPNST. In this case, the postoperative course was good, and 16 months after the operation, the patient is currently under observation at the outpatient stage without recurrence. CONCLUSIONS: MPNST in the oesophagus is a relatively rare disease. Diagnosis before treatment is sometimes difficult, but the prognosis is good if radical resection is possible.

Prognostic significance of neutrophil-lymphocyte ratio in resectable pancreatic neuroendocrine tumors with special reference to tumor-associated macrophages.

BACKGROUND: Recent studies have shown that the systemic inflammatory response induced by cancer leads to cancer progression. Neutrophil-to-lymphocyte ratio (NLR) is the most reliable marker to detect systemic inflammation. In this study, we investigated the significance of NLR in patients with well-differentiated pancreatic neuroendocrine tumors (PanNETs) according to the World Health Organization 2017 classification. METHODS: We retrospectively collected data for patients with PanNET who underwent pancreatic resection with curative intent between January 2008 and December 2017 at six institutions. Clinicopathological factors, recurrence, and immunohistochemical staining of tumor-associated macrophages (TAMs) were analyzed in a total of 55 patients in this study. RESULTS: High NLR (>3.41) in patients was significantly associated with higher white blood cell count, higher Ki-67 index, higher mitotic count, higher grade, higher incidence of lymph node metastasis, higher incidence of lymphatic and neural invasion, massive blood loss, and a large number of CD163-expressing TAMs. Recurrence-free survival of patients with high NLR was significantly poorer than that of patients with low NLR. Multivariate analysis identified high NLR, NET Grade 2 (G2) or Grade 3 (G3), and synchronous hepatic resection as independent risk factors for recurrence after curative resection. CONCLUSIONS: NLR is a promising predictor of recurrence after pancreatectomy that needs to be further investigated and that accumulation of TAMs in the tumor could be one of the causes of NLR elevation.

Significance of Lymph Node Metastasis in Resectable Well-differentiated Pancreatic Neuroendocrine Tumor.

OBJECTIVES: Understanding the effect of lymph node metastasis (LNM) on prognosis in pancreatic neuroendocrine neoplasm is helpful for surgery and follow-up. In this study, we investigated the significance of LNM in well-differentiated pancreatic neuroendocrine tumors (PanNETs) according to the World Health Organization 2017 classification. METHODS: We retrospectively collected data for 95 consecutive patients with PanNET who underwent pancreatic resection with curative intent between January 2008 and December 2017 at 6 institutions. The clinicopathological factors were compared in patients with and without LNM, and prognostic factors were analyzed. RESULTS: Lymph node metastasis was significantly associated with malignant potential of PanNET, such as larger tumor size, higher Ki-67 index, higher tumor grade, and higher incidence of lymphatic, vessel, and neural invasion. Lymph node metastasis was also associated with disease-free but not overall survival. Multivariate analysis identified NET grade 2 (G2) and G3 as independent risk factors for recurrence after curative resection. CONCLUSIONS: World Health Organization 2017 classification was the most independent prognostic factor in patients with resectable well-differentiated PanNETs. Patients with G2 and higher-grade tumors require lymph node dissection to improve prognosis.

[A Case of Ascending Colon Cancer Recurrence with Para-Aortic Lymph Node Metastases That Was Successfully Treated with Resection and Adjuvant Chemotherapy].

A laparoscopy-assisted right hemicolectomy and D3 lymph node dissection were performed to treat a 60-year-old woman with ascending colon cancer. Microscopically, the resected specimen was diagnosed as adenocarcinoma(tub1>tub2, pSS, pN1, M0). Adjuvant chemotherapy using UFT/UZEL was administered for 6 months. Enlarged para-aortic lymph nodes were identified by follow-up CT 2 years post operation, and a para-aortic lymph node dissection was performed. Microscopic examination revealed that the #216 b1 int lymph node contained poorly differentiated metastatic adenocarcinoma. After 36 courses of FOLFOX as adjuvant chemotherapy, the chemotherapy was discontinued because of an adverse event. She has remained well without recurrence for 5 years after the second surgery. There have been reports of survival improvements by surgical resections in patients with solitary para-aorta lymph node metastases of colorectal cancer. These observations suggest that the surgical therapy may have contributed to the improved prognosis in the present case.

Transvaginal Hybrid NOTES Procedure for Treatment of Gallstone Ileus.

Gallstone ileus is a rare mechanical bowel obstruction, and previously reported cases have been treated laparoscopically with good results. Although transvaginal hybrid NOTES without a minilaparotomy has been reported to decrease the incidence of surgical wound complications, to our knowledge, this procedure has not been used previously to treat gallstone ileus. We present a case of a 63-year-old woman who underwent transvaginal hybrid NOTES procedure for treatment of gallstone ileus. This case was admitted to our hospital following acute-onset abdominal pain and vomiting. We diagnosed gallstone ileus with cholecystoduodenal fistula by computed tomography and performed totally laparoscopic surgery using only three 5 mm abdominal ports with transvaginal specimen extraction and enterectomy. The patient's postoperative course was uneventful, and laparoscopic cholecystectomy and fistula repair were performed 8 months after the initial surgery. The patient experienced additional pain relief and good cosmetic outcomes. In conclusion, using transvaginal hybrid NOTES may become a future option to minimize the invasiveness of other laparoscopic procedures.

A case of splenic metastasis of ovarian cancer treated with complete laparoscopic splenectomy and transvaginal specimen extraction.

A 61-year-old woman was diagnosed with right inguinal lymph node and splenic metastasis of ovarian serous cystadenocarcinoma. We performed right inguinal lymph node dissection and total laparoscopic splenectomy in the supine position followed by transvaginal specimen extraction (TVSE). First, using three ports, we extracted the right inguinal lymph node. We repaired the posterior wall of the inguinal canal using a mesh plug. We added two ports and displaced the spleen from the retroperitoneum and lifted it using a snake retractor, disconnecting the hilum using an automatic suturing device. Next, the posterior wall of the vagina was intraperitoneally incised. And an Alexis® laparoscopic system was inserted into the vagina. The cap maintained aeroperitoneum, a collection bag was inserted in the abdominal cavity via the vagina, and the spleen was collected. When the spleen was removed from the body, partial fragmentation of the organ was required in the bag. Organ fragmentation was performed only within the bag, and we made sure not to tear the bag. The vaginal wound was laparoscopically sutured. The patient had no operative complications and was able to actively ambulate at the first day after surgery due to a slight postoperative pain. Total laparoscopic splenectomy with TVSE in the supine position may be a safe and feasible method for selected female patients. This technique enables minimally invasive surgery for female patients with splenic disease.

Relationship between CD147 and expression of amino acid transporters (LAT1 and ASCT2) in patients with pancreatic cancer.

CD147 functions as an induction of matrix metalloproteinases and tumor angiogenesis, and is highly expressed in various malignant neoplasms. Recently, CD147 is shown to form a complex with amino acid transporters such as L-type amino acid transporter (LAT1), system ASC amino acid transporter-2 (ASCT2) and 4F2hc as a heavy chain of LAT1. It remains unknown about the existence of these complexes in patients with pancreatic cancer. The aim of this study is to investigate the relationship between CD147 and these amino acid transporters. Ninety-seven patients with pancreatic cancer were evaluated. Tumor sections were stained by immunohistochemistry for LAT1, ASCT2, Ki-67, microvessel density (MVD) determined by CD34, p-AKT, and p-mTOR. CD147 was highly expressed in 23% (22/97) of patients. A high expression of CD147 is significantly associated with N factor, LAT1, ASCT2, Ki-67, VEGF and p-mTOR. A high CD147 expression was identified as a significant prognostic predictor by univariate survival analysis. The coexpression of CD147 and LAT1, and that of CD147 and 4F2hc yielded a significantly worse prognosis than the single expression of LAT1, and that of 4F2hc, respectively. CD147 revealed a significant relationship with the expression level of LAT1 and ASCT2, correlated with tumor proliferation, angiogenesis and mTOR signaling.

Clinicopathological significance of ASC amino acid transporter-2 expression in pancreatic ductal carcinoma.

AIMS: ASC amino acid transporter-2 (ASCT2) is highly expressed in cancer cells. However, the clinicopathological significance of ASCT2 expression in pancreatic cancer remains unclear. The aim of this study was to investigate the clinical significance of ASCT2 expression in pancreatic cancer. METHODS AND RESULTS: Ninety-seven patients with surgically resected pancreatic ductal adenocarcinoma were evaluated. Tumour sections were stained by immunohistochemistry for ASCT2, Ki67, CD34 (to determine microvessel density), phospho-AKT (p-AKT) and phospho-mammalian target of rapamycin (p-mTOR) expression. ASCT2 was expressed in 54% (52/97) of tumours. Statistically significant differences in patient age, T stage, N stage, lymphatic permeation, vascular invasion, Ki67, and CD34 and p-mTOR expression were observed between tumours with and without ASCT2 expression. Multivariate analysis confirmed that vascular invasion, ASCT2 expression and Ki67 expression were independent predictive factors for a poorer prognosis. CONCLUSIONS: ASCT2 expression plays an important role in tumour cell growth, and is a promising pathological marker for predicting a worse outcome in pancreatic cancer.

Extraperitoneal colostomy in laparoscopic abdominoperineal resection using a hand inserted from the perineal side.

INTRODUCTION: Extraperitoneal colostomy is considered to be more effective at preventing post-colostomy complications than intraperitoneal colostomy. However, this operation is difficult via laparoscopic surgery alone. We present an extraperitoneal colostomy technique using a hand inserted from the perineal side. MATERIALS AND SURGICAL TECHNIQUE: Extraperitoneal colostomy was performed in five patients. After the rectum was resected, a hand was inserted into the abdominal cavity from the perineal side, and pneumoperitoneum was created. The peritoneum was dissected to make the extraperitoneal route, and the proximal colon was passed along this route with fingers and laparoscopic manipulation. All procedures were completed without tissue damage or hemorrhage. No patient developed a hernia or ileus postoperatively. DISCUSSION: Laparoscopic abdominoperineal resection for an extraperitoneal colostomy is difficult via laparoscopic ports only. It can be simplified by operating with manual assistance via the perineal wound.

Clinical significance of L-type amino acid transporter 1 expression as a prognostic marker and potential of new targeting therapy in biliary tract cancer.

BACKGROUND: The expression of L-type amino acid transporter 1 (LAT1) has been described to play essential roles in tumor cell growth and survival. However, it remains unclear about the clinicopathological significance of LAT1 expression in biliary tract cancer. This study was conducted to determine biological significance of LAT1 expression and investigate whether LAT1 could be a prognostic biomarker for biliary tract cancer. METHODS: A total of 139 consecutive patients with resected pathologic stage I-IV biliary tract adenocarcinoma were retrospectively reviewed. Tumor specimens were stained by immunohistochemistry for LAT1, Ki-67, microvessel density determined by CD34, and p53; and prognosis of patients was correlated. Biological significance of LAT1 expression was investigated by in vitro and in vivo experiments with LAT inhibitor, 2-aminobicyclo-(2,2,1)-heptane-2-carboxylic acid (BCH) using cholangiocarcinoma cell line. RESULTS: In total patients, high LAT1 expressions were recognized in 64.0%. The expression of LAT1 was closely correlated with lymphatic metastases, cell proliferation and angiogenesis, and was a significant indicator for predicting poor outcome after surgery. LAT1 expression was a significant independent predictor by multivariate analysis. Both in vitro and in vivo preliminary experiments indicated that BCH significantly suppressed growth of the tumor and yielded an additive therapeutic efficacy to gemcitabine and 5-FU. CONCLUSIONS: High expression of LAT1 is a promising pathological marker to predict the outcome in patients with biliary tract adenocarcinoma. Inhibition of LAT1 may be an effective targeted therapy for this distressing disease.

[A case of Barrett's esophageal carcinoma treated with combined therapy].

During a routine health examination, a 50-year-old man was found to have an elevated lesion at the esophagogastric junction. Poorly differentiated adenocarcinoma was diagnosed from the biopsy findings. Computed tomography showed metastases in the mediastinal, intra-abdominal, and paraaortic lymph nodes. The clinical stage diagnosis was cT2, cN4, cM0, cStage IVa. Combination chemotherapy with docetaxel, CDDP, and 5-FU (DCF) was started initially. After 2 courses of DCF, the primary lesion and mediastinal lymph nodes had decreased in size, but the intra-abdominal lymph node had grown. A curative operation with paraaortic lymph node dissection was considered possible; thus, video-assisted thoracoscopic surgery of the esophagus with 3-field lymph node dissection was performed. The final findings revealed Barrett's esophageal carcinoma, EG, 0-III,23×18 mm, mod-por, CT-pT1b (sm3) pN4, sM0, fStage IV. Histologically, the mediastinal lymph node metastases disappeared with chemotherapy, but no reduction was observed in the abdominal lymph nodes. After surgery, 2 courses of combination adjuvant chemotherapy with CDDP and 5-FU were administered along with 50 Gy of radiotherapy. Subsequently, the treatment was changed to tegafur-gimeracil-oteracil potassium alone on an outpatient basis. The patient remains recurrence free 22 months postsurgery.

A case of amoebic liver abscess complicated by a gastric fistula cured with oral medication only.

A 26-year-old man was admitted to our hospital because of a high-grade fever and abdominal pain. A blood test showed marked inflammation. Enhanced computed tomography (CT) showed an 8.0×6.0cm cystic lesion in the left hepatic lobe. Esophagogastroduodenoscopy showed a huge egg-yolk-like mass in the gastric submucosa in the lesser curvature of the gastric body from the gastric angle. There were 3 ulcers on the mass, out of which milky pus flowed. Trophozoites of Entamoeba histolytica were detected from cultures of the liver abscess and a biopsy of the gastric ulcers. The amoebic dysentery antibody titer was increased 1600 times. An amoebic liver abscess complicated by a gastric fistula was diagnosed. As therapy, oral metronidazole was administered for 2 weeks without percutaneous drainage. The systemic inflammatory findings improved immediately and the abscess decreased markedly in size.

[A case of gastric cancer with lung, Virchow and para-aortic lymph node metastases treated successfully using PTX/5'-DFUR].

A 6 3-year-old male presented with dysphagia. Gastrointestinal endoscopic examination showed advanced gastric cancer type 3, which was diagnosed as well-differentiated adenocarcinoma. Computed tomography(CT)showed bilateral lung tumors, hugely enlarged Virchow and para-aortic lymph nodes. He was treated with combination chemotherapy of weekly paclitaxel(PTX)and doxifluridine(5'-DFUR). PTX was administered at a dose of 80mg/m2 on day 1, 8 and 15, and 5'- DFUR was orally administered at a dose of 533mg/m / 2day for 5 days followed by withdrawal for 2 days. After four courses of treatment, CT showed an almost complete disappearance of the lung and lymph node metastases. After 13 courses of treatment, total gastrectomy and lymph node dissection were performed. One year postoperatively, the patient died of a recur- rence.

The effect of nicorandil on small intestinal ischemia-reperfusion injury in a canine model.

BACKGROUND: It has been shown that nicorandil, which has both ATP-sensitive K+ (KATP) channel opener-like and nitrate-like properties, has an organ-protective effect in ischemia-reperfusion injury in several experimental animal models. AIMS: We evaluate the effectiveness of nicorandil on warm ischemia-reperfusion injury of the small intestine in a canine model. METHODS: Eighteen beagle dogs were divided into three groups: the control group (n=6); the nicorandil group (n=6), to which nicorandil was injected intravenously before the ischemia; and the glibenclamide group (n=6), to which glibenclamide, which closes the KATP channel and does not suppress the nitrate effect of nicorandil, was orally administered, and then nicorandil was injected in the same manner as in the nicorandil group. Both the superior mesenteric artery and vein were clamped for 2 h. Superior mesenteric artery blood flow, small intestinal mucosal tissue blood flow, intramucosal pH, and histopathological analyses were compared among the three groups. RESULTS: Superior mesenteric artery blood flow, mucosal tissue blood flow and pHi after reperfusion were significantly maintained in the nicorandil in comparison with the control and the glibenclamide groups. The histopathological findings showed less severe mucosal damage after reperfusion in the nicorandil group compared with the other two groups. Between the control group and the glibenclamide group, no significant differences were observed in all those parameters. CONCLUSION: This study suggests that nicorandil has a protective effect on small intestinal IR injury, and activation of KATP channels plays an important role in inhibiting small intestinal IR injury.

Large cell neuroendocrine carcinoma of the ampulla of vater with adenocarcinoma and squamous cell carcinoma components.

A 73-year-old woman visited our hospital complaining of general fatigue and jaundice. Laboratory tests revealed an elevated total bilirubin, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase and γ-glutamyltransferase. Computed tomography and magnetic resonance imaging demonstrated a mass lesion at the ampulla of Vater with dilatation of the common bile duct and main pancreatic duct. Percutaneous transhepatic cholangiography revealed dilatation of the bile duct and a negative filling defect due to the tumor. Pancreatoduodenectomy was performed. The specimen included an ulcerated firm tumor of the papilla Vater. The surface of the ampulla consisted of well-differentiated papillary adenocarcinoma, whereas the deep layer, such as submucosal or muscular layer, contained large cell neuroendocrine carcinoma and squamous cell carcinoma. Immunohistochemistry revealed that the large cell neuroendocrine carcinoma component was positive for chromogranin A, synaptophysin and CD56. The patient died from multiple liver and bone metastases 13 months after surgery. This is a very rare case of a large cell neuroendocrine carcinoma accompanied by adenocarcinoma and squamous cell carcinoma components.

Direct hemoperfusion with a polymyxin B-immobilized cartridge in intestinal warm ischemia reperfusion.

AIM: To investigate the effectiveness of direct hemoperfusion with polymyxin B-immobilized fibers (DHP-PMX therapy) on warm ischemia-reperfusion (I/R) injury of the small intestine. METHODS: The proximal jejunum and distal ileum of mongrel dogs were resected. Warm ischemia was performed by clamping the superior mesenteric artery (SMA) and vein (SMV) for 2 h. Blood flow to the proximal small intestine was restored 1 h after reperfusion, and the distal small intestine was used as a stoma. The experiment was discontinued 6 h after reperfusion. The dogs were divided into two groups: the DHP-PMX group (n = 6, DHP-PMX was performed for 180 min; from 10 min prior to reperfusion to 170 min after reperfusion) and the control group (n = 5). The rate pressure product (RPP), SMA blood flow, mucosal tissue blood flow, and intramucosal pH (pHi) were compared between the two groups. The serum interleukin (IL)-10 levels measured 170 min after reperfusion were also compared. RESULTS: The RPP at 6 h after reperfusion was significantly higher in the PMX group than in the control group (12 174 +/- 1832 mmHg/min vs 8929 +/- 1797 mmHg/min, P < 0.05). The recovery rates of the SMA blood flow at 1 and 6 h after reperfusion were significantly better in the PMX group than in the control group (61% +/- 7% vs 44% +/- 4%, P < 0.05, and 59% +/- 5% vs 35% +/- 5%, P < 0.05, respectively). The recovery rate of the mucosal tissue blood flow and the pHi levels at 6 h after reperfusion were significantly higher in the PMX group (61% +/- 8% vs 31% +/- 3%, P < 0.05 and 7.91 +/- 0.06 vs 7.69 +/- 0.08, P < 0.05, respectively). In addition, the serum IL-10 levels just before DHP-PMX removal were significantly higher in the PMX group than in the control group (1 569 +/- 253 pg/mL vs 211 +/- 40 pg/mL, P < 0.05). CONCLUSION: DHP-PMX therapy reduced warm I/R injury of the small intestine. IL-10 may play a role in inhibiting I/R injury during DHP-PMX therapy.

Precision interferometry for measuring wavefronts of multi-wavelength optical pickups.

A novel wavefront measurement interferometer is developed that enables the user to evaluate the wavefronts of multi-wavelength optical pickups. In this interferometer, instead of transparent pinholes used in Mach-Zehnder interferometers, reflection dot pinhole mirrors are used to generate reference wavefronts for different wavelengths which make the optical system very flexible and simple compared with those using transparent pinholes. The interferometer is designed to operate at wavelengths of 405 nm, 650 nm and 780 nm over an NA range of up to 0.95, which is very difficult to realize when transparent pinholes are used for generating reference wavefronts. The three-beam problem is solved and the optics of the interferometer is simplified by employing a software filter instead of using spatial filters in the optics of the interferometer. The instrument has an equal optical path length that enables the user to measure pickups with a very short coherence length. A new method by which asymmetric aberration components, such as astigmatic and coma aberrations, can be calibrated by rotating the measured lens with 90 and 180 degrees is proposed and the calibration results are verified by using a high precision reference point source. System accuracy is also evaluated by comparing with the measurement results obtained by commercial Fizeau type interferometer and a good agreement is achieved.

Ectopic varices rupture in the gastroduodenal anastomosis successfully treated with N-butyl-2-cyanoacrylate injection.

The term "ectopic varices" is used to describe dilated portosystemic collateral veins in unusual locations other than the gastroesophageal region. We recently experienced a rare case of ectopic varices that developed in the gastroduodenal anastomosis after subtotal gastrectomy. A 70-year-old male with liver cirrhosis due to hepatitis C virus infection was admitted for hematemesis and tarry stool. He had received a subtotal gastrectomy with the Billroth-I method for gastric ulcer at 46 years of age. Although emergency endoscopy revealed esophageal and gastric fundal varices, there were no obvious bleeding points. After removal of the coagula, ectopic varices and a fibrin plug were observed on the gastroduodenal anastomosis. During the observation, blood began to spurt from the fibrin plug. N-butyl-2-cyanoacrylate with lipiodol injection succeeded in hemostasis. Splenic angiography showed gastric varices feeding from a short gastric vein and the posterior gastric vein. The blood flow around the bleeding point, as indicated by lipiodol deposition, had decreased, and no feeding vein was observed. Endoscopic and angiographic findings are shown and the treatment for such lesions is discussed.

Effect of the free radical scavenger MCI-186 on pulmonary ischemia-reperfusion injury in dogs.

BACKGROUND: Free radical scavengers and superoxide dismutase have been found to protect against cerebral ischemic damage, and it was suggested that oxygen free radicals contribute to ischemia-reperfusion injury induced by cerebral ischemic damage. MCI-186 (3-methyl-1-phenyl-2-pyrazolin-5-one) is a potent scavenger and inhibitor of hydroxyl radicals and protective agent of peroxidative injury. The purpose of this study was to evaluate the effects of MCI-186 on pulmonary ischemia-reperfusion injury in a simulated transplanted lung model. METHODS: Fourteen dogs were divided into two groups (n = 7 each). In the MCI group, MCI-186 was continuously administered at 3 mg/kg/hour intravenously (IV) from 30 minutes before reperfusion until 30 minutes after reperfusion (total administration time 1 hour). Vehicle was administered in the control group. Warm ischemia was induced for 3 hours by clamping the left pulmonary artery and veins. Simultaneously, the left stem bronchus was bisected and then anastomosed before reperfusion. The right pulmonary artery was ligated 15 minutes after reperfusion, and the right stem bronchus was then bisected. RESULTS: The respiratory gas exchange, hemodynamic changes, wet-to-dry weight ratio (WDR) and malondialdehyde (MDA) concentration in the tissue were significantly improved (p < 0.05) in the MCI group. The histologic damage was more severe in the control group and polymorphonuclear neutrophil (PMN) infiltration was reduced in the MCI group. CONCLUSION: MCI-186 has a protective effect on pulmonary ischemia-reperfusion injury through the inhibition of lipid peroxidation.