Clinical course and rebleeding predictors of acute haemorrhagic rectal ulcer: 5-year experience and review of the literature.

AIM: This study was carried out to clarify the clinical features of acute haemorrhagic rectal ulcer (AHRU) and to determine the risks and predictors of AHRU rebleeding. METHOD: Forty patients with AHRU were retrospectively analysed. Patient characteristics, endoscopic features and clinical course were investigated and predictors of AHRU rebleeding were analysed. RESULTS: All patients were in a bedridden state as a result of various diseases, and many patients had atherosclerosis-related comorbidities such as hypertension (67.4%), diabetes mellitus (40.0%) and chronic kidney disease (42.5%). All patients had hypoalbuminaemia, 75% of patients were using antithrombotic drugs and 25% of patients were using systemic corticosteroids. Based on colonoscopy, all patients developed ulcers in the distal rectum just above the dentate line and 30% of patients developed whole circumferential ulcers. The median interval between the onset of the bedridden state and the first massive haematochezia was 16 days and 50% of all patients developed rebleeding regardless of the presence or absence of haemostatic therapy. The median time from initial haemostasis to rebleeding was 6 days. Univariate analysis and stepwise multivariate analysis revealed that whole circumferential ulcer (P = 0.036) was a significant independent predictor of AHRU rebleeding. CONCLUSION: In the present study, we elucidated the clinical features of AHRU in detail and reviewed previous reports of AHRU. Rebleeding of AHRU occurred at a high rate and whole circumferential ulcer was a significant independent predictor of AHRU rebleeding.

Value of fluorine-18-FDG-PET to monitor hepatocellular carcinoma after interventional therapy.

METHODS: Thirty-two tumors in 30 patients with hepatocellular carcinoma (HCC) were studied preoperatively using PET with 18F-labeled 2-fluoro-2-deoxy-D-glucose (FDG) to evaluate the metabolic activity of the lesions after interventional therapy. All patients had received transcatheter arterial chemoembolization therapy using iodized oil (Lipiodol, Laboratoire Guerbet, Alnaysous-Bois, France) before the PET study. The tumors were 2 to 18 cm in diameter. FDG uptake at 48 to 60 min after tracer injection was used to determine the standardized uptake value (SUV). The SUVs of the tumor and nontumor regions of the liver were calculated to obtain the tumor-to-nontumor ratio (SUV ratio). The PET results were compared with the findings of CT and histologic examination. RESULTS: The tumors were divided into three types, consisting of those with increased FDG uptake (SUV ratio of 1.07-2.66, Type A, n = 19), similar FDG uptake to the surrounding nontumor region (SUV ratio of 0.77-1.04, Type B, n = 7) and decreased or absent FDG uptake (SUV ratio of 0.13-0.58, Type C, n = 6). In histologic examination, viable HCC tissue remained in all Type A and B tumors, whereas more than 90% necrosis was found in the Type C tumors, indicating that interventional therapy had been effective. These PET findings reflected tumor viability more accurately than the extent of intratumor Lipiodol retention on CT images. CONCLUSION: FDG-PET appears to be a valuable method for the assessment of tumor viability after interventional therapy for HCC.

In vivo assessment of glucose metabolism in hepatocellular carcinoma with FDG-PET.

UNLABELLED: The present study was designed to assess glucose metabolism in hepatocellular carcinoma (HCC) with PET and [18F]fluorodeoxyglucose (FDG) and to compare the results with the measured in vitro enzymatic activity of glucose metabolism and the histologic grading of HCC. METHODS: Dynamic FDG-PET scans were obtained in 17 preoperative patients with HCC. From the serial tissue and arterial radioactivities obtained by dynamic PET, FDG kinetic rate constants (K1 to k4) were obtained. The standardized uptake value (SUV) was also determined from the images acquired 48 to 60 min after FDG administration. These PET results were compared with hexokinase and glucose-6-phosphatase (G6Pase) activities and histologic grading of HCC in surgically resected tumor materials. According to histologic grading, the tumors were divided into low-grade and high-grade HCCs. RESULTS: The k3 and SUV of high-grade HCCs were significantly higher than those of low-grade HCCs (p < 0.005, each). In addition, high correlations were observed between the hexokinase activities and these two parameters (r = 0.715 0.768, respectively). In some HCCs, relatively high G6Pase activities and k4 values modified tumor FDG uptake. CONCLUSION: FDG PET is a valuable method for assessing glucose metabolism and histologic grading of HCC.

Expression of glucose transporters in human pancreatic tumors compared with increased FDG accumulation in PET study.

UNLABELLED: Although overexpression of GLUT-1 glucose transporter has already been reported in human cancers, the mechanism of glucose entry into pancreatic cancers remains unknown. To evaluate the relationship between GLUT glucose transporters and FDG uptake, FDG-PET was performed in 34 preoperative patients (mean age, 60.9 yr) with suspected pancreatic tumors, including 28 malignant and 6 benign tumors. METHODS: FDG uptake at 50 min after injection of 185 MBq of [18F]FDG with >5 hr of fasting was semiquantitatively analyzed as standardized uptake values (SUVs). The GLUT expression was studied by immunohistochemistry of paraffin sections from these tumors after operation using anti-GLUT-1, -2, -3, -4 and -5 antibodies to obtain immunohistochemical grading ("strong," "weak" and "negative") by three experienced physicians. RESULTS: Of 26 malignant tumors proved by histological examination, 23 (88%) tumors were positive for the expression of GLUT-1 glucose transporter, and 17 (61%) showed strong expression. On the other hand, 13 (46%), 0 (0%), 9 (36%) and 13 (46%) malignant tumors were positive for the expression of GLUT-2, -3, -4 and -5 glucose transporters, respectively. Three of six benign tumors showed strong GLUT-1 expression. Concerning GLUT-2, -3, -4 and -5, only one benign tumor showed positive GLUT-5 expression. Thus, GLUT-1 showed relatively high sensitivity but low specificity (50%) for detecting malignant tumors, whereas GLUT-2, -3, -4 and -5 had lower sensitivities but higher specificities. Correlations between SUVs and grading of GLUT immunoreactivity were significant in GLUT-1 (strong, 4.49 +/- 2.95; weak, 3.42 +/- 1.21; negative, 2.52 +/- 0.84) (p < 0.05) but not in the remaining four GLUT transporters. CONCLUSION: These data indicate that GLUT-1 has a significant role in the malignant glucose metabolism and may contribute to the increased uptake of FDG in PET imaging in patients with pancreatic tumor.

Value of fluorine-18-fluorodeoxyglucose and thallium-201 in the detection of pancreatic cancer.

UNLABELLED: This study compares the diagnostic value of 18F-FDG PET imaging and 201TI-SPECT imaging in patients with pancreatic cancer. METHODS: Twenty-five patients with histologically-proven pancreatic cancer were studied. Following PET transmission scanning, 3 mCi of 201TI were administered after patients had fasted overnight. Thallium-201-SPECT images were obtained 15 min later. Immediately after 201TI-SPECT imaging, 4 mCi of FDG were administered and PET images were obtained 60 min later. The PET and SPECT images were compared qualitatively and quantitatively. For quantitative analysis, 10 x 10 mm2 regions of interest (ROIs) were selected in areas of the tumor showing the highest tracer accumulation and in the normal pancreas. The tumor to nontumor activity ratio (T/N ratio) was calculated. RESULTS: Although both techniques delineated focal lesions with an increase in tracer accumulation in 16 patients, PET identified eight additional patients in whom 201TI-SPECT images did not visualize any lesion. Thus, FDG-PET provided significantly higher sensitivity (96%) than 201TI-SPECT (64%). Among the patients showing increased tracer accumulation, the T/N ratio was significantly higher with FDG-PET (3.24 +/- 1.27) than with 201TI-SPECT (1.77 +/- 0.37) (p < 0.0001). CONCLUSION: We conclude that FDG-PET has a larger clinical value for noninvasive detection of pancreatic cancer than 201TI-SPECT. If a PET camera is available, FDG-PET is considered to be the method of choice for the evaluation of patients with suspected pancreatic cancer.

FDG uptake, GLUT-1 glucose transporter and cellularity in human pancreatic tumors.

UNLABELLED: We previously reported that grading of GLUT-1 glucose transporter expression was related closely to FDG accumulation in FDG PET in human cancers. But in this strong GLUT-1 expression group, there was an enormous range of standardized uptake values (SUVs) within them. METHODS: To evaluate other factors determining the FDG PET uptake, FDG PET was performed in 36 preoperative patients (mean age 62.0 yr) suspected of having pancreatic tumors, including 33 malignant and 3 benign neoplastic tumors. FDG uptake at 50 min after injection of 185 MBq 18F-FDG with > 5 hr fasting condition was semiquantitatively analyzed as SUVs. The GLUT-1 expression was studied by immunohistochemistry of paraffin sections from these tumors after the operation using the antiGLUT-1 antibody. The number of tumor cells within a 5- x 5-mm square was counted manually using x200 magnification photographs and was graded immunohistochemically as strong, weak or negative. RESULTS: In all 36 cases there were 3 cases of GLUT-1 negative, 8 of GLUT-1 weak positive and 25 of GLUT-1 strong positive. In all cases, the total number of tumor cells had no significant value for SUVs. Among 33 GLUT-1 positive cases, the number of GLUT-1 positive tumor cells correlated significantly with SUVs (p < 0.01). Only in 25 strong grade cases, the number of GLUT-1 strong positive tumor cells had a more significant value for SUVs (p < 0.005). Computational multivariate analysis using multiple regression for SUVs was performed evaluating the five variables as follows: tumor size, GLUT-1 immunohistochemical grading, number of total tumor cells, number of total GLUT-1 positive tumor cells and number of GLUT-1 strong positive cells. This analysis revealed that only the variable, the number of GLUT-1 strong positive cells, had a significant regression coefficient for SUVs (standard regression coefficient = 0.855, p < 0.0001). CONCLUSION: These data indicate that GLUT-1 expression plays an essential role in higher FDG accumulation in pancreatic tumor FDG PET, and the cellularity has a significant influence on SUVs only in the condition of GLUT-1 strong positive expression.

[An autopsy case of well differentiated leiomyosarcoma of the jejunum].

A 54-year-old man had a leiomyosarcoma of the jejunum, 8 X 6 X 5 cm in size resected, on December 17, 1982 and died of liver metastases with hemorrhagic ascites (4,000 ml) on July 5, 1984. The malignant potential of a smooth muscle tumor based on the mitotic index of tumor cells has been stressed for many years. However, our biologically malignant autopsy case showed not only an exceptionally low mitotic index in tumor cells of the surgical specimen but also in those of the autopsy specimen. In this report, the fact that the degree of mitotic figures sometimes fail to indicate biological behavior is discussed.

[Imaging of somatostatin receptor using 111In-pentetreotide].

Recently radiolabeled somatostatin analog, [111In]pentetreotide, was developed and its usefulness for the diagnosis and localization of neuroendocrine tumors has been described. In this paper, we reported the results of [111In]pentetreotide scintigraphy in four patients with gastroenteropancreatic endocrine tumors. Two patients with metastatic gastrinoma, one patient with gastric carcinoid, and one patient suspected with gastrinoma, were injected with 119-156 MBq of [111In]pentetreotide. Planar and SPECT images were obtained 4, 24, and 48 hours postinjection. Both primary and metastatic tumors were well visualized in patients with metastatic gastrinoma. Especially in one patient small liver metastases which were not detected by CT or MRI were imaged. We could not obtain positive images in the other two patients. Four-hour or 24-hr images were better than 48-hr images because of higher count density and lower gut activity. No significant adverse effect were seen in any patient. [111In]pentetreotide scintigraphy is a useful procedure for the localization of gastroenteropancreatic endocrine tumors.

[MR angiography in the evaluation of endoscopic injection sclerotherapy for esophago-gastric varices].

We evaluated the utility of magnetic resonance angiography (MRA) for the detection of esophago-gastric varices and assessment of their therapeutic response to endoscopic injection sclerotherapy (EIS). MRA was performed in a total of 12 patients with esophago (E)-gastric (G) varices (V) (9 EV and 3 GV patients) both before and two-weeks after EIS. 25-35 horizontal images were obtained during single breath holding and data were reconstructed by using the two dimension time of flight method. MRA detected varicose lesions in all GV patients and in 7 of 8 EV patients of the grades F2 or higher. Varicose lesion in grade F1 EV patients were initially undetectable before EIS but became evident on MRA after EIS. The portal collaterals were equally well displayed by MRA and the superior mesenteric arteriography at its portogram phase. MRA and endoscopy were concordant for the disappearance or persistence of varicose lesions after EIS. We conclude that MRA is useful for the detection of esophago-gastric varices and other portal collaterals. MRA provides a non-invasive and workable technique in evaluation of patients with esophago-gastric varices undergoing EIS.