Toyokazu Kawano

Endoscopic ultrasonography of superficial esophageal cancers using a thin ultrasound probe system equipped with switchable radial and linear scanning modes

BACKGROUND Detailed information on the depth of invasion of superficial esophageal cancer is required for endoscopic mucosal resection. As a pretherapeutic diagnostic procedure, endoscopic ultrasonography using conventional 7.5 MHz systems has been ineffective at providing sufficient details. A newly developed, thin ultrasound probe system provides both radial and linear scanning for evaluation of superficial esophageal cancer. METHODS Endoscopic ultrasonography was performed in 16 patients using a switchable probe driven at 20 MHz. Seventeen lesions of superficial esophageal cancer were evaluated for depth of invasion to discriminate mucosal from submucosal penetration. RESULTS The overall accuracy of staging was 64.7%. In all six errors, mucosal cancers were overstaged as submucosal invasion. The diagnostic accuracy was 80% when the muscularis mucosae was visualized. CONCLUSION A 20 MHz linear-radial switchable probe is a useful new method in the staging of superficial esophageal cancer.

Synchronous multiple colorectal adenocarcinomas.

The object of the present work was to characterize clinical features and the quality of preoperative examinations in patients with synchronous colorectal carcinomas, and to compare the incidence of associated benign polyps with our findings in patients with a single malignant lesion.

Clinical impact of strip biopsy for early gastric cancer.

BACKGROUND The impact of EMR (strip biopsy method) on the selection of subsequent treatment for early gastric cancer was analyzed retrospectively. METHODS A total of 163 consecutive patients with gastric epithelial tumors (186 lesions) underwent strip biopsy. On the basis of pretherapeutic findings, the indications for strip biopsy were classified into 4 groups: benign-malignant borderline group (93 lesions), curative indication group (65), diagnostic indication group (22), and palliative indication group (6). The clinical impact of the strip biopsy result on the subsequent treatment strategy was assessed. RESULTS Of the lesions in the benign-malignant borderline group, 36.6% were intramucosal cancer. In the curative indication group, the results of strip biopsy differed from the pretherapeutic findings for 7.7% of the lesions. Strip biopsy was effective treatment for all lesions in the benign-malignant borderline group and for 92.3% of those in the curative indication group. Strip biopsy avoided unnecessary surgery in 50% of patients in the diagnostic indication group and 16.7% of those in the palliative indication group. After the strip biopsy results were explained, 50% of the patients in the palliative indication group reversed their initial decision and opted for surgery. Strip biopsy results reversed the decision for surgery, which had been based on inaccurate pretherapeutic information, in 20% of cases of early gastric cancer. CONCLUSIONS Strip biopsy has a major clinical impact, because it provides an accurate diagnosis, aids in the selection of an appropriate treatment strategy, and reduces unnecessary surgery.

Prognostic value and interobserver agreement of endoscopic ultrasonography for superficial squamous cell carcinoma of the esophagus: a prospective study.

Background and Aims. Submucosal invasion of superficial esophageal cancer (SEC) is related to the prognosis. We prospectively analyzed outcomes of SEC in patients staged by endoscopic ultrasonography (EUS).Patients and Methods. We staged 31 endoscopically diagnosed SEC cases using a 20/15-MHz thin probe. The EUS tumor stage was classified as EUSM (limited within mucosa), EUS-SM (with submucosal invasion), or EUS-MP over (invading the muscularis propria or deeper). Lymph node metastasis and 2-yr survival were analyzed according to the EUS tumor stage in 29 squamous cell carcinoma cases. Interobserver agreement of the EUS stage was tested between the examiner and a blind reviewer.Results. Lymph node metastasis was significantly frequent in the EUS-SM group (8 of 18 cases [44.4%]) compared with the EUS-M group (1 of 10 cases [10%]) (p=0.03). Patient survival at 2 yr after initial therapy was 72.2% in the EUS-SM group and 90% in the EUS-M group. Death from cancer was noted only in the EUS-SM group (three cases). The accuracy rates of EUS tumor staging were 74.1% by the examiner and 66.7% by the blind reviewer, with moderate interobserver agreement (κ=0.46).Conclusions. Thin-probe EUS can classify SEC into two groups: the EUS-M group with excellent outcome and the EUS-SM group with a significant risk of lymph node metastasis.

p53 Mutations in Two Patients with Intraductal Papillary Adenoma of the Pancreas

There has been no report on p53 gene mutation in benign human pancreatic intraductal tumors. We examined pancreatic juice and tissue specimens from two patients with intraductal papillary adenoma of the pancreas by polymerase chain reaction‐single‐strand conformation polymorphism analysis and direct sequencing and found point mutations of p53 gene resulting in amino acid substitutions in exons 6 and 8. Thus, p53 gene mutation may be an early event in the neoplastic process of some pancreatic intraductal tumors and may play an important role in tumorigenesis.

Epstein-barr virus association is rare in esophageal squamous cell carcinoma

AbstractBackground. A critical role of Epstein-Barr virus (EBV) in carcinogenesis of nasopharyngeal squamous cell carcinoma and gastric adenocarcinoma is strongly suspected. We analyzed the possible EBV association for Japanese squamous cell carcinoma (SCC)-dominant esophageal cancer cases. Methods. We retrospectively screened 36 surgically resected esophageal cancer lesions from 36 patients maily with SCC using in situ hybridization (ISH) for EBV-encoded small RNA1 (EBER-1). EBV DNA analysis using real-time quantitative polymerase chain reaction (Q-PCR) was performed for three recent cases. Results. We found no EBER-1-positive cancer cell in any tested esophageal cancer lesion. There were many EBER-1-positive tumor-infiltrating lymphocytes in the basaloid SCC lesion and a small number of positive lymphocytes in the other five advanced SCC lesions (14.7% of SCC). One SCC lesion with a highcopy number of EBV DNA had EBER-1-positive lymphocytes. Conclusions. EBV is rarely associated with esophageal SCC, and may appear through tumor-infiltrating lymphocytes in some advanced lesions.

Strip biopsy to treat esophageal granular cell tumor

Esophageal granular cell tumors are rare neoplasms. We successfully treated a 35-year-old Japanese man with an esophageal granular cell tumor without any complications using strip biopsy. Endoscopic ultrasonography revealed a hypoechoic tumor with a diameter of 8 mm that was confined to the submucosal layer. A strip biopsy done with a two-channel endoscope completely resected the tumor. Six months later, no abnormal findings were recognized in the resected area. Therefore we propose that strip biopsy be considered as a viable alternative treatment for esophageal granular cell tumor, depending on the histologic character, tumor size, and depth of tumor infiltration.

Ruptured amebic liver abscess.

We treated two patients with a ruptured amebic liver abscess. The diagnosis was made at a relatively early stage and treatment was successful for one patient, but an accurate diagnosis of liver abscess was not made and invasive extraintestinal amebiasis led to multiple organ failure and to death for the other. Neither patient had been outside of Japan, and both were heterosexual. The origins of Entamoeba histolytica infection could not be determined. Though the mortality rate is high in cases of ruptured amebic liver abscess, appropriate management can lead to a good prognosis.

Thin-probe endoscopic ultrasonography for surgical resection of early colorectal neoplasms: A pilot study

Purpose: To retrospectively analyze the results of our therapeutic recommendations for EMR and surgical operation using thin-probe EUS for patients with early colorectal neoplasms. Methods: We retrospectively analyzed the therapeutic recommendation for using EUS and the results in 63 lesions of 63 patients. When the depth of the change for the third layer (submucosal layer) was 1 millimeter or more, we recommended surgical operation(EUS operation-recommended group). Results: Surgical operation was suitable for all of lesions in the EUS-operation-recommended group (23 lesions of 23 patients). Conclusion: We think that a change of 1 millimeter or more in the third layer (corresponding to the submucosal layer) in EUS for colorectal neoplasms may be a useful finding for surgical decision making. Correspondence to: Hideo Yanai, Department of Clinical Research, National Hospital Organization Kanmon Medical Center, 1-1 Sotoura, Shimonoseki-752-8510, Japan, Tel: +81-83-2411199; Fax: 81-83-241-1301; E-mail: yanaih@kanmon-mc2. hosp. go. jp

Prediction of Lymph Node Metastasis in Early Gastric Carcinoma by Immunohistochemical Analysis and its Clinical Application.

1986年から1995年に施行した早期胃癌手術326症例のうちリンパ節転移を認めた21例について, ホルマリン固定パラフィン包埋切片を用いてABC法にて癌関連遺伝子であるp53, c-erb B2, cyclin E, CD44について免疫組織学的検討をおこない, その陽性率について対象群40例と比較検討した. p53, cyclin E, CD44のいずれにおいても陽性率は転移群で有意に高率であり, 3遺伝子ともに陽性を示した症例はn (+) 群: 7/21 (33%), n (-) 群: 3/40 (8%) で. n (+) 群で有意に高率であった. さらにcyclin EまたはCD44が強陽性を示した7例は全例がn (+) 群であった. 1996年度の手術症例29例について, 生検標本において転移高危険群と判定した症例は計4例で, n (+) の2例はもれなく含まれていた. 以上より, p53, cyclin E, CD44陽性症例ではリンパ節転移の危険性が極めて高いことを考慮すべきで, 生検組織による術前判定が可能であり, 最適の治療法や術式の決定に活用できるものと考えられた.