Tsugio Kitamura

Endoscopic ultrasonography in diagnosis and staging of pancreatic cancer

The accuracy of endoscopic ultrasonography (EUS) for diagnosis of pancreatic cancers was evaluated in consecutive 232 patients with possible pancreatic cancer, and that for assessment of their locoregional spread was evaluated in 28 patients with pancreatic cancer subjected to pancreatectomy, in comparison with the accuracies of transabdominal ultrasonography (US) and computed tomography (CT). EUS was found to be significantly more accurate than US or CT and was especially useful for detecting small pancreatic cancers of less than 2 cm in diameter. With EUS, pancreatic cancers could be detected as a hypoechoic mass with a relatively unclear margin and irregular internal echoes. EUS was also more sensitive than CT and US for detecting venous and gastric invasions: it was more useful for detecting direct invasion of pancreatic cancers when the tumors were less than 3 cm in diameter. These findings indicate that EUS is an accurate method for diagnosis of pancreatic cancer and assessment of their locoregional spread and is particularly useful for detecting small tumors.

Synthetic Methods for the Generation and Preparative Application of Benzyne

Many methods have been developed for generating benzyne. Convenient and reliable precursors extensively studied so far involve benzenediazonium-2-carboxylate and o-dihalobenzenes such as 1,2-bromofluorobenzene and 1,2-dibromobenzene. Recently, in addition to the above precursors, o-(trimethylsilyl)phenyl triflate has been put into frequent use for benzyne reactions, in which benzyne is efficiently generated under mild conditions using fluoride ion. Furthermore, o-(trimethylsilyl)phenyliodonium triflate has been developed as a more efficient benzyne precursor. This mini-review focusses on recent progress in benzyne chemistry from the viewpoint of organic synthesis. The methods for generating benzynes are classified by the conditions into four categories: basic conditions using strong bases, mild conditions using fluoride ion, thermolysis, and oxidation.

Effectiveness of periodic checkup by ultrasonography for the early diagnosis of hepatocellular carcinoma.

Periodic checkup by ultrasonography was conducted on patients with chronic liver diseases for early detection of hepatocellular carcinoma. in 19 months, a total of 2004 examinations were performed on a total of 660 cases (179 cases with liver cirrhosis in the compensatory stage, younger than 70 years; 481 cases with chronic hepatitis, aged 40 to 70 years for men and 50 to 70 years for women). of the 660 cases, 22 HCC cases (3.3%) were detected and finally diagnosed by angiography and/or histologic examination. Four of those cases (18%) had a single nodule smaller than 1 cm in diameter, and 11 cases (50%) had a single nodule smaller than 2 cm. Surgical resection was performed on 12 cases (55%). in comparison with the control group (83 HCC cases not receiving any periodic checkup), the frequency of small liver cancer and the surgical resection rate in the study group were significantly higher. This examination system by periodic ultrasonography checkup of patients with chronic hepatic diseases was effective for early detection and permitted aggressive therapy of hepatocellular carcinoma.

A Practical and Convenient Fluorination of 1,3-Dicarbonyl Compounds Using Aqueous HF in the Presence of Iodosylbenzene

A simple, practical, and convenient fluorination of 1,3-dicarbonyl compounds was achieved by direct use of aqueous hydrofluoric acid and iodosylbenzene (PhIO). The reaction of ethyl benzoylacetate with the reagent system of aqueous HF and PhIO in CH(2)Cl(2) gave ethyl 2-fluoro-2-benzolyacetate in 98% yield. Other 1,3-dicarbonyl compounds including β-keto esters and 1,3-diketones underwent the fluorination reaction to give the corresponding fluorinated products in good yields.

Palladium-catalyzed intramolecular hydroarylation of 4-benzofuranyl alkynoates. Approach to angelicin derivatives.

Intramolecular hydroarylation of 4-benzofuranyl alkynoates using Pd(OAc)(2) as catalyst took place selectively and efficiently, giving angular furocoumarin derivatives in high yields. The parent angelicin was obtained in 80% yield by this method. The starting 4-benzofuranyl alkynoates were easily accessible from readily available 4-hydroxybenzofurans and alkynoic acids.

Recent advances in ultrasonographic diagnosis of hepatocellular carcinoma

The diagnostic accuracy of ultrasonography (US) for hepatocellular carcinoma (HCC) was estimated by checking against the regional cancer registry, and also the clinical features, major therapy, and prognosis of HCC cases diagnosed by initial US were examined for the two periods of 1980 and 1984. The number of patients with HCC was 83 of 4442 in 1980 and 86/3393 in 1984. As for the detectability of the tumor, the sensitivity improved from 94.0% to 96.5%. Regarding the ability to confirm the detected tumor to be HCC, the sensitivity improved from 53.0% to 68.6% without decrease in the specificity of 99.9%. The size and number of nodules were more accurately diagnosed in 1984, and cases with small (⩽4 cm) single nodule increased from 2% to 9%. Active therapy was performed in more cases and the 2‐year survival rate increased from 9% to 20%. The remarkable improvement was achieved in the diagnostic accuracy of US for HCC during 4 years from 1980 to 1984.

Diagnostic accuracy of ultrasonography for hepatocellular carcinoma

Accuracy of ultrasonography for the diagnosis of hepatocellular carcinoma (HCC) was examined. The subjects were 5339 patients who underwent ultrasonography of the upper abdomen, during the year 1980 at our hospital. Out of 5339, 113 cases were found to be hepatocellular carcinoma by a 3‐year follow‐up study, checking against the records of regional cancer registry. Diagnostic accuracy based on 6 months of follow‐up was as follows: for identification of liver tumors, sensitivity, specificity, and overall accuracy were 94.9%, 98.7%, and 98.9% respectively; for diagnosis of HCC, sensitivity, specificity, and overall accuracy were 58.9%, 99.9%, and 99.3% respectively. In conclusion, the ability of ultrasonography to detect hepatocellular carcinoma is adequately high, and thus, ultrasonography can be employed as a diagnostic procedure for mass screening. Cancer 58:344–347, 1986.

Hypervalent Iodine-Mediated Fluorination of Styrene Derivatives: Stoichiometric and Catalytic Transformation to 2,2-Difluoroethylarenes.

Fluorination of styrene derivatives with a reagent system composed of μ-oxo-bis[trifluoroacetato(phenyl)iodine] and a pyridine·HF complex gave the corresponding (2,2-difluoroethyl)arenes in good yields. Similarly, the reagent of PhI(OCOCF3)2 and the pyridine·HF complex acted as a fluorinating agent for styrene derivatives. The fluorination of styrene derivatives with the pyridine·HF complex underwent under catalytic conditions using 4-iodotoluene as a catalyst and m-CPBA as a terminal oxidant.

Drastic effect of bidentate phosphine ligands on Pd-catalyzed hydroarylation of ethyl propiolate: a simple route to arylbutadienes

Palladium complexes with bidentate phosphine ligands, Pd(dppe)(OAc)(2) and Pd(dppm)(OAc)(2), were found to be effective catalysts for reactions of simple arenes with ethyl propiolate, affording arylbutadiene derivatives selectively.

Diagnosis of hepatic cavernous hemangioma by fine needle aspiration biopsy under ultrasonic guidance.

Percutaneous aspiration biopsy of the liver using a heparinized 22-gauge needle was performed under ultrasonic guidance in 11 patients with hepatic cavernous hemangioma. Ten (91%) of 11 biopsy specimens obtained were cytologically diagnostic for hemangioma. No indications of malignancy were found. There was no relation between the cytological diagnosis and the location, size, or ultrasonographic findings. No complications were encountered.These findings indicate that cytological examination of the liver by fine needle aspiration biopsy is useful in diagnosing hepatic cavernous hemangioma of any size and in any location, provided optimal route to the lesions is chosen.