Yoshiharu Satake

Sedation Practices for Gastrointestinal Endoscopy in Europe, North America, Asia, Africa and Australia

Gastroscopy and colonoscopy are standard practice for diagnosing upper gastrointestinal and colonic diseases. Sedation improves tolerance of the endoscopic procedures, but may be responsible for about 50% of the complication rate of the examination. Data from countries of the five continents regarding the rate of using sedation for gastrointestinal endoscopy are rare. We performed a literature search (PubMed) to identify published national or international studies and summarize data on the rate of using sedation for diagnostic gastrointestinal endoscopic procedures in countries of Europe, North America, Asia, Africa and Australia. In continents where data were not available, we used mailed questionnaires to endoscopy centers in countries of these continents. Our data indicate that the use of sedation for diagnostic gastrointestinal endoscopy is high in North America and Australia, but varies considerably among countries in Europe, Asia and Africa.

Endoscopic Hemostasis in Hemorrhagic Gastric Ulcer—Effectiveness of the Hemoclipping, Ethanol Injections and Heat Probe—

Abstract: The hemostatic effects of hemoclipping, the pure ethanol local injection method and the heat probe methods on hemorrhagic gastric ulcers associated with exposed blood vessels, were compared. The locations of the ulcers and exposed blood vessles, as well as characteristics and the severity of the hemorrhage were discussed. The hemoclipping method was used on 59 patients, the pure ethanol local injection on 32 patients, and the heat probe methods on 26 patients. The hemoclipping and pure ethanol local injection methods were effective in all of the patients in whom the exposed blood vessels were present around the margin of ulcers. The efficacy rate was 91%, 92% and 92%, respectively, when exposed blood vessels were found at the base of the ulcer. The efficacy rate was 94%, 100% and 80% for the three hemostatic methods, respectively, when an oozing hemorrhage was present. The three methods had an efficacy rate of 100% when only blood clots were present. The efficacy rate for a spurting hemorrhage was 86%, 71% and 67%, respectively, for the three methods. The hemoclipping and pure ethanol local injection were effective in 100% of slight and moderate hemorrhage cases, while the heat probe method was effective in only 89% of moderate cases. The efficacy rate was 85%, 85% and 83%, respectively, for severe cases. Overall, the efficacy rate was 93% for the hemoclipping method, 94% for the pure ethanol local injection and 92% for the heat probe method, and there was no significant difference between the three methods with regard to the overall efficacy rate.

Endoscopic and Histopathological Study about 25 Cases of Minute Superficial Depressed Neoplastic Lesions in the Large Intestine

Abstract: We studied 25 cases of minute (less than 5 mm in a diameter) superficial depressed neoplastic lesions during the period of March 1990 to September 1991. These depressed neoplastic lesions were recognized by colonoscopy as asteroid redness with surrounding elevation. The thickness and height of the surrounding elevations were modified by air volume. Occasionally, they seemed according to the air volume to be elevated lesions, though their fundamental form was confirmed as being superficial depressed lesions from observations of histopathological sections and using a dissecting microscope. The endoscopic figures were emphasized by sprinkling them with Methylene Blue.

Cellular and Structural Atypia of the Early Colorectal Cancers

Cellular and structural gland atypia in lesions of early colorectal cancer removed by endoscopic polypectomy in 101 patients were histopathologically studied. The following results were observed. Cellular atypia was frequently found in lesions with a high rate of nuclear polarity loss and multiple nuclear mitoses (99. 0%). The most frequent findings in the glands with structural atypia was intraglandular glands and crowding of neoplastic glands (85. 1%). Most of the appearances of the cellular and structural atypias showed no marked relationship with the sizes of the lesions, depth of invasion and association of adenoma components. Early cancer had both cellular and structural atypia in 95% of the patients and could be diagnosed by conventional histopathological criteria. However five patients with early cancer showed no structural atypia and were diagnosed as having cellular atypia. These cancers were early intramucosal cancer and four lesions were associated with adenoma components 20 mm or less in size. The loss of nuclear polarity and nuclear pleomorphism may be considered more important than nuclear stratification and mitoses in the diagnosis of early cancer.

Present Status of Early Colorectal Cancer in Japan

We examined and clinicopathologically analyzed 422 patients with early colorectal cancer that we encountered, and discussed the problems typical of early colorectal cancers in Japan.

Is the Histogenesis of 6‐10 mm Early Colorectal Cancer Different from that of Larger Cancers?

Abstract: Out of a total of 466 cases of early colorectal cancer, we analyzed 139 cases with submucosal invasion (sm cancer) according to tumor size, gross appearance, depth and degree of invasion, and the presence of adenoma components. Early colorectal cancers 11 ‐20 mm in diameter were the most common lesion in this group, and the percentage with sm cancer increased with tumor size. More than 70% of relatively small sm cancers, 6‐10 mm in diameter, had moderate or massive submucosal invasion similar to that found in large sm cancers. Only 35% of 6‐10 mm cancers had an adenoma component; the majority (65%) had no adenoma component. In marked contrast, 63% of sm cancers 11 ‐20 mm in diameter had an adenoma component and in sm cancer the percentage of tumors composed solely of cancerous tissue without an adenoma component was low. Similar results were obtained when only protruding type sm cancers, which accounted for the majority of sm cancer cases, were included in the analysis. Therefore, we believe that the protruding type sm cancer 6‐10 mm in diameter is at a stage close to advanced cancer. It is possible that many 6‐10 mm sm cancers have a histogenesis different from that of large sm cancers.

“Does non‐protruded neoplasm in the large intestine exist ?”

Several warm encouraging letters were sent in response to the paper “Endoscopic and Histopathological Study about 25 Cases of Minute Superficial Depressed Neoplastic Lesions in Large Intestine” which appeared in Dig. Endosc., 1993, 5;3-12 with questions touching several core issues. The doctors who wrote were ; Vincenzo Speranza, M.D. (Universita Degli STUD1 Diroma, Professor of Surgery), Simon K. Lo, M.D. (Harbor-UCLA Medical Center, Director of Endoscopy & Assicuate Chief), G.N. Tytgat, M.D. (Academisch Ziekenhuis bil de Universiteit van Amsterdam, Professor), Charles J. Lightdale, M.D. (Memorial Sloan-Kettering Cancer Center, Director of Endoscopic Research) and Melvin Schapiro, M. D. (President of 10th World Congress of Gastroenterology). The questions can be summarized as follows : First, what is the true incidence of such depressed lesions ? Second, what is their relevance to colon cancers? Third, what is the natural history of these lesions? Are they the earlier forms of the typical elevated ademonas ? Fourth, are they seen as so in other ethnic groups ? We would like to introduce our recent data concerning colonic non-protruded neoplasm. We have thought that this term might be more appropriate for the lesions than superficial depressed neoplastic lesions, since the lesions that were classified as tumor components were recognized at a slightly depressed or level even with the surrounding normal colonic mucosa. We studied 127 colorectal early cancers (invasions had to be within submucosal layers) and 4252 adenomas, both protruded or non-pro-

Endoscopic Therapy of Early Gastric Cancer —Comparison of Endoscopic Mucosal Coagulation and Resection—

Abstract: The clinical efficacy of various methods of endoscopic treatment was evaluated in 70 patients with early gastric cancer. The treatments included using an Nd‐ YAG laser on 22 patients (2 IIa cases, 3 IIa + IIc cases and 17 IIc cases), a heater probe on 2 patients (IIc) and endoscopic mucosal resection (EMR) on 46 patients (13 I cases, 15 IIa cases, 2 IIa + IIc cases and 16 IIc cases). Laser irradiation and the heater probe method (endscopic mucosal coagulation; EMC), which cause coagulation and necrosis to lesions using heat energy, were found to be successful for well differentiated adenocarcinoma confined to the mucosa even if the size of the lesions was 20 mm and over. Poorly differentiated adenocarcinoma with lesions 20 mm or smaller reoccurred, and only well differentiated adenocarcinoma with infiltration limited to the mucosa seemed to be treatable endoscopically by EMR. Whether or not total resection was possible was determined with respect to the size and site of lesions in patients treated by EMR. Great therapeutic efficacy was achieved when the lesions were 10 mm or smaller and located in the anterior wall or the greater curvature. Piecemeal resection had to be made in a majority of cases when the lesions measured 10 mm or more or were located in the lesser curvature or the posterior wall. Therefore, endoscopic EMR is recommended if the size of the lesions is 10 mm or less, while EMC must also be considered if the lesions are larger or piecemeal resection is required.