Shintaro Akamoto

18F-fluorodeoxyglucose positron emission tomography in the diagnosis of small pancreatic cancer

AIM To investigate the role of (18)F-fluorodeoxyglucose positron emission tomography (FDG-PET) in the diagnosis of small pancreatic cancer. METHODS This study involved 31 patients with proven invasive ductal cancer of the pancreas. The patients were divided into 3 groups according to the maximum diameter of the tumor: TS1 (maximum tumor size ≤ 2.0 cm), TS2 (> 2.0 cm and ≤ 4.0 cm) or TS3-4 (> 4.0 cm). The relationships between the TS and various diagnostic tools, including FDG-PET with dual time point evaluation, were analyzed. RESULTS The tumors ranged from 1.3 to 11.0 cm in diameter. Thirty of the 31 patients (97%) had a positive FDG-PET study. There were 5 patients classified as TS1, 15 as TS2 and 11 as TS3-4. The sensitivity of FDG-PET, computed tomography (CT) and magnetic resonance imaging (MRI) were 100%, 40%, 0% in TS1, 93%, 93%, 89% in TS2 and 100%, 100%, 100% in TS3-4. The sensitivity of FDG-PET was significantly higher in comparison to CT and MRI in patients with TS1 (P < 0.032). The mean standardized uptake values (SUVs) did not show a significant difference in relation to the TS (TS1: 5.8 ± 4.5, TS2: 5.7 ± 2.2, TS3-4: 8.2 ± 3.9), respectively. All the TS1 tumors (from 13 to 20 mm) showed higher SUVs in FDG-PET with dual time point evaluation in the delayed phase compared with the early phase, which suggested the lesions were malignant. CONCLUSION These results indicate that FDG-PET with dual time point evaluation is a useful modality for the detection of small pancreatic cancers with a diameter of less than 20 mm.

Neutrophil Elastase Inhibitor (Sivelestat) Preserves Antitumor Immunity and Reduces the Inflammatory Mediators Associated with Major Surgery

PurposeTo examine the effects of the administration of perioperative sivelestat, a selective neutrophil elastase inhibitor, on tumor immunity and inflammatory mediators in patients who undergo major surgery.MethodsThirteen patients admitted to the hospital for elective surgery were equally randomized into one of two groups: the Sivelestat group (n = 6) and the control group (n = 7). Thereafter, the immunosuppressive acidic protein (IAP), serum interleukin-6 (IL-6), and type 1/type 2 T-helper cell balance were all assessed at several time points before and after surgical intervention.ResultsThe serum IL-6 values at 1 and 12 h after surgery and on postoperative days 1 and 3 were all significantly lower in the sivelestat group than in the control group. The IAP values at postoperative days 7 and 28 in the sivelestat group were also significantly lower than those in the control group. There was a significant correlation between the IL-6 level at 1 h after surgery and the IAP level at postoperative days 7 and 28.ConclusionsIn this preliminary study, the perioperative administration of sivelestat was thus suggested to reduce surgical stress by decreasing the cytokine release and preserving the antitumor immunity.

Lymphatic vessel invasion detected by monoclonal antibody D2-40 as a predictor of lymph node metastasis in T1 colorectal cancer.

ObjectiveWhen selecting patients who are at high risk for lymph node metastasis, the detection of lymphatic vessel invasion (LVI) is important. We investigated LVI detected by D2-40 staining as a predictor of lymph node metastasis in T1 colorectal cancer.Materials and methodsClinicopathological factors including LVI were investigated in 136 patients who underwent colectomy with lymph node dissection for T1 colorectal cancer. We used immunostaining with monoclonal antibody D2-40 to detect LVI.ResultsLymph node metastases were found in 18 patients (13.2%), and LVI were detected in 45 (33%); lymph node metastasis was more frequently observed in LVI-positive groups (13/45 vs 5/91, p < 0.001). Both univariate and multivariate analyses revealed that LVI detected by D2-40 and a poorly differentiated histology at the invasion front were independent risk factors of lymph node metastasis.ConclusionLVI detected by D2-40 is important for the prediction of lymph node metastasis.

Extraperitoneal colostomy in laparoscopic abdominoperineal resection using a laparoscopic retractor

Although extraperitoneal colostomy is often performed to prevent postoperative parastomal hernia formation following an open abdominoperineal resection of lower rectal cancer, it has not been widely employed laparoscopically because of the difficulty associated with the extraperitoneal route. This paper describes a laparoscopic extraperitoneal sigmoid colostomy using the Endo Retract™ Maxi instrument. This surgical technique is easy, and helps to prevent the development of parastomal hernias.

Global metabolic reprogramming of colorectal cancer occurs at adenoma stage and is induced by MYC

Significance Metabolic reprogramming is one of the hallmarks of cancer. However, the underlying mechanisms that regulate cancer metabolism are poorly understood. Here we performed multiomics-based analysis of paired normal–tumor tissues from patients with colorectal cancer, which revealed that the protooncogene protein MYC regulated global metabolic reprogramming of colorectal cancer by modulating 215 metabolic reactions. Importantly, this metabolic reprogramming occurred in a manner not associated with specific gene mutations in colorectal carcinogenesis. For many years, small-molecule or biologic inhibitors of MYC have been required. Here we demonstrate that knockdown of MYC downstream pyrimidine synthesis genes contributes to the suppression of colorectal cancer cell proliferation similar to MYC, and thus pyrimidine synthesis pathways could be potential targets for colorectal cancer therapy. Cancer cells alter their metabolism for the production of precursors of macromolecules. However, the control mechanisms underlying this reprogramming are poorly understood. Here we show that metabolic reprogramming of colorectal cancer is caused chiefly by aberrant MYC expression. Multiomics-based analyses of paired normal and tumor tissues from 275 patients with colorectal cancer revealed that metabolic alterations occur at the adenoma stage of carcinogenesis, in a manner not associated with specific gene mutations involved in colorectal carcinogenesis. MYC expression induced at least 215 metabolic reactions by changing the expression levels of 121 metabolic genes and 39 transporter genes. Further, MYC negatively regulated the expression of genes involved in mitochondrial biogenesis and maintenance but positively regulated genes involved in DNA and histone methylation. Knockdown of MYC in colorectal cancer cells reset the altered metabolism and suppressed cell growth. Moreover, inhibition of MYC target pyrimidine synthesis genes such as CAD, UMPS, and CTPS blocked cell growth, and thus are potential targets for colorectal cancer therapy.

Surgical approach for extrahepatic metastasis of HCC in the abdominal cavity.

BACKGROUND/AIMS Despite recent development of therapeutic strategies for intrahepatic lesions, standard guidelines for treatment of extrahepatic metastases of hepatocellular carcinoma have not been established. METHODOLOGY Surgical resection for intra-abdominal extrahepatic metastases of hepatocellular carcinoma was performed on 10 patients at our institution between 1992 and 2008. We retrospectively examined the clinicopathologic features and significance of a surgical approach in these patients. RESULTS Nine of the 10 patients received treatment for primary hepatocellular carcinoma before surgery for intra-abdominal extrahepatic metastasis. A simultaneous intrahepatic lesion was detected in half of the patients when the extrahepatic metastasis was resected. Extrahepatic recurrent organs included adrenal glands, lymph nodes, abdominal wall, stomach and diaphragm. The mean survival period after resection was 36.1 months. Two patients are still alive without further recurrence. One patient died of retroperitoneal recurrence and 7 died of intrahepatic recurrence or liver failure after resection. CONCLUSIONS With careful case selection, considering that not all extrahepatic metastases suggest systemic spread of hepatocellular carcinoma, surgical treatment for metastatic lesions in the abdominal cavity can provide a relatively good prognosis.

Localized malignant mesothelioma in the middle mediastinum: Report of a case

Localized malignant mesothelioma in the mediastinum is rare and most known cases have been reported as “localized malignant pericardial mesothelioma.” We report a case of a middle mediastinal tumor, which we were able to resect completely. Histopathological examination of the tumor confirmed that it was a malignant epithelial lymphohistiocytoid mesothelioma. We assumed that the tumor was derived from the pericardium. Local recurrence was detected 1 year after resection, and the patient died of the disease about 2 years later.

Hand-assisted laparoscopic partial splenectomy using an endopath monopolar sealer.

A partial splenectomy is a good way to prevent postsplenectomy infections by preservation of the immune role of the spleen for select patients. Although a laparoscopic total splenectomy is a safe and feasible treatment modality, the laparoscopic approach has not been generally adopted for a partial splenectomy because of technical difficulties. The hand-assisted technique provides an excellent means to explore, to retract safely, and to apply immediate hemostasis in solid organ resection. The hand-assisted laparoscopic partial splenectomy using an endopath monopolar sealer (Salient EndoSH2.0 Monopolar Sealer) was performed successfully. The segmental arteries and veins were isolated and divided using a tactile feedback. Splenic parenchyma was dissected and sealed using an endopath monopolar sealer. The surgical field was almost bloodless during the parenchymal transection and the transection time was around 15 minutes. The hand-assisted laparoscopic approach allows partial splenectomy as a safe and bloodless surgery for select patients.

Spontaneous perforation in collagenous colitis

Fig 1. Contrast-enhanced computed tomography of the abdomen indicating edema (arrow) and gas (arrowhead) within the bowel wall of the descending colon. A 64-YEAR-OLD WOMAN with a history of depression treated by mianserin was admitted to our hospital with acute abdominal pain. She had no history of other drug use. Abdominal tenderness with peritoneal signs was observed in the left upper quadrant. This was preceded for 2 weeks by nonbloody diarrhea and appetite loss. Laboratory tests indicated a leukocyte count of 11,930/mm and a C-reactive protein level of 13.69 mg/dL. Contrast-enhanced computed tomography of the abdomen indicated edema and gas within the bowel wall of the descending colon (Fig 1). Ischemic colitis and necrosis of the descending colon were suspected, and an emergency laparotomy was performed. Gas bubbles were detected in the mesentery and subserous layer of the descending colon. Wall thickening and an inflammatory change were also detected, but there were no macroscopic signs of peritonitis or necrosis in the descending colon. Left-sided colectomy and transverse colostomy were performed. Grossly, the specimen exhibited multiple longitudinal ulcers. Histopathologic examination indicated typical findings of collagenous colitis (CC) with a thick subepithelial collagenous band and an ulcerated area with mesentery penetration (Fig 2). The postoperative course was uneventful.

Beneficial effect of D-allose for isolated islet culture prior to islet transplantation

Pretransplant restoration of islets damaged during isolation remains to be solved. In this study, we examined the effect of D‐allose on islets isolated from rat pancreata prior to islet transplantation.