Background—Ablation lesion depth caused by radiofrequency-based renal denervation (RDN) was limited to <4 mm in previous animal studies, suggesting that radiofrequency-RDN cannot ablate a substantial percentage of renal sympathetic nerves. We aimed to define the true lesion depth achieved with radiofrequency-RDN using a fine sectioning method and to investigate biophysical parameters that could predict lesion depth.Methods and Results—Radiofrequency was delivered to 87 sites in 14 renal arteries from 9 farm pigs at various ablation settings: 2, 4, 6, and 9 W for 60 seconds and 6 W for 120 seconds. Electric impedance and electrode temperature were recorded during ablation. At 7 days, 2470 histological sections were obtained from the treated arteries. Maximum lesion depth increased at 2 to 6 W, peaking at 6.53 (95% confidence interval, 4.27–8.78) mm under the 6 W/60 s condition. It was not augmented by greater power (9 W) or longer duration (120 seconds). There were statistically significant tendencies at 6 and 9 W, with higher injury scores in the media, nerves, arterioles, and fat. Maximum lesion depth was positively correlated with impedance reduction and peak electrode temperature (Pearson correlation coefficients were 0.59 and 0.53, respectively).Conclusions—Lesion depth was 6.5 mm for radiofrequency-RDN at 6 W/60 s. The impedance reduction and peak electrode temperature during ablation were closely associated with lesion depth. Hence, these biophysical parameters could provide prompt feedback during radiofrequency-RDN procedures in the clinical setting.

Background. There has been extensive use of serum tumor markers in diagnosing pancreatic adenocarcinoma. There is no tumor marker, however, that alone has sufficient diagnostic accuracy. It is necessary to know which combination of tumor markers should be used to detect pancreatic cancer, with respect to clinical usefulness and cost effectiveness. Methods. Serum levels of 17 kinds of tumor markers were determined in 145 patients and 40 healthy volunteers. Thirty‐five patients with proven pancreatic adenocarcinoma, and 32 with benign pancreatobiliary disease (14 chronic pancreatitis and 18 biliary stones) were selected. For analysis of the usefulness of each tumor marker to differentiate these two groups, scatterplot and relative operating characteristic (ROC) analyses were used. A multivariate discriminant system to differentiate these two groups was developed using stepwise discriminant analysis by backward elimination selection. Results. The significance of each tumor marker varied according to the tumor volume. By ROC analysis, the markers were divided into four subgroups according to their usefulness in discriminating pancreatic adenocarcinoma from benign pancreatobiliary disease. A discriminant system consisting of two different discriminant functions using nine tumor markers (CA 19–9, DUPAN‐2, TPA, elastase‐1, lipase, amylase, γ‐glutamyl transpeptidase, alkaline phosphatase, and lactate dehydrogenase) was developed and designated CAMPAS‐P; it could differentiate between all 35 cases of pancreatic adenocarcinoma and 32 cases of benign pancreatobiliary disease. On the other hand, CAMPAS‐P showed a low positive rate in pancreatic tumors of unusual histologic type, and poor organ‐specific diagnostic ability in various digestive organ malignancies. Conclusions. CAMPAS‐P may be very useful for differential diagnosis between pancreatic adenocarcinoma and benign pancreatobiliary disease.

The serum levels of CA 125 and CA 19-9 were determined by an immunoradiometric assay employing the monoclonal antibody OC 125 and anti-CA 19-9 antibody in 88 patients with ovarian carcinoma. When a cut-off value of CA 125 was set below 35 U/ml in the control group, serum elevated levels of CA 125 were found in 86.7% of the patients with surgically demonstrable ovarian serous cystadenocarcinoma, in 100% (4/4 cases) of clear-cell carcinoma, in 50% (2/4 cases) of endometrioid carcinoma, in 100% (5/5 cases) of undifferentiated carcinoma, and in 80% of the recurrent cases. Using a cut-off value of 37 U/ml, serum elevated levels of CA 19-9 were detected in 68.2% of mucinous cystadenocarcinoma, in 28.9% of serous cystadenocarcinoma, in 75% (3/4 cases) of metastatic ovarian carcinoma, and in 37.5% of the recurrent cases. A statistical analysis of the combination assay using CA 125, CA 19–9, tissue polypeptide antigen (TPA), immunosuppressive acidic protein (IAP), ferritin and CEA was carried out by multivariate method (discriminatory analysis) in 45 patients with ovarian carcinoma and 50 healthy subjects. As a result before treatment, positive rates of a single tumor marker were 79.7% with CA 125, 42.7% with CA-19-9, 73.1% with IAP, 61.7% with TPA, 64.3% with ferritin and 25.4% with CEA, respectively. A combination assay of these markers was useful for detecting identification of ovarian carcinoma, by which it gave a higher accuracy of ovarian cancer detection.

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