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Dive into the research topics where Tsutomu Isa is active.

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Featured researches published by Tsutomu Isa.


American Journal of Surgery | 2001

Predictive factors for long-term survival in patients with intrahepatic cholangiocarcinoma

Tsutomu Isa; Toshiomi Kusano; Hideaki Shimoji; Yoshitaka Takeshima; Yoshihiro Muto; Masato Furukawa

BACKGROUND In order to elucidate the predictive factors for long-term survival in patients with intrahepatic cholangiocarcinoma (ICC), we evaluated 7 patients who survived for more than 5 years (5-year survivors). METHODS We examined the clinicopathologic and biologic factors of the 5-year survivors, and these findings were then compared with those in 20 patients who died within 5 years after surgery (control group). RESULTS In the 5-year survivors, the gross appearance of the tumors included a mass-forming (MF) type in 5 cases, an intraductal growth (IG) type in 1, and another type (microcarcinoma with hepatolithiasis) in 1. No case demonstrated a periductal infiltrating (PI) type. Except for 1 case with an IG type tumor, no lymph node metastasis was seen in any patients. All of the 5-year survivors were classified from stage I to III, and all also underwent a curative resection. The clinicopathologic factors demonstrating significant differences between the 5-year survivors and the control group included the gross type of the tumor, lymph node involvement, the surgical margin, curability, and pTNM stage. CONCLUSION The predictive factors for long-term survival in patients with ICC are thus suggested to include not only tumor staging and curability, but also lymph node metastasis and the gross type of the tumors.


Journal of Clinical Gastroenterology | 2001

Natural progression of untreated hepatolithiasis that shows no clinical signs at its initial presentation

Toshiomi Kusano; Tsutomu Isa; Mitsuji Ohtsubo; Takahiro Yasaka; Masato Furukawa

Goals To elucidate the natural progression of hepatolithiasis that showed no signs at the time of initial presentation. Study Over a 17-year period, we observed 122 of 311 patients with hepatolithiasis who reported no symptoms and, thus, who received no treatment at initial presentation. The follow-up period was for up to 15 years (mean, 10.08 years). Results Fourteen of 112 patients (11.5%) developed some symptoms attributed to hepatolithiasis. The interval until the onset of symptoms ranged from 9 months to 7.33 years (mean, 3.42 years ). The developing symptoms included abdominal pain, hepatic abscess, cholangitis, and cholangiocarcinoma. Nine of the 14 patients (64.3%) developed stone migration to the extrahepatic bile duct at the onset of clinical symptoms. The incidence of lobar liver atrophy on computed tomography in the patients with symptomatic hepatolithiasis (13 of 14 patients; 92.9%) was significantly higher than that in the patients with asymptomatic hepatolithiasis (14 of 108 patients; 13.0%). The prognosis of the patients with symptomatic hepatolithiasis were as follows: 2 died of cholangiocarcinoma, 1 died of hepatic failure, and 11 survived. Fifteen of asymptomatic patients died, but none of these deaths were attributed to hepatolithiasis. Conclusions Close observation is an alternative management at initial presentation for patients with asymptomatic hepatolithiasis without extrahepatic stones or lobar liver atrophy.


Digestive Surgery | 1999

Radiation-Associated Rectal Cancer: Report of Four Cases

Osamu Tamai; Eiji Nozato; Hiroshi Miyazato; Tsutomu Isa; Shungo Hiroyasu; Masayuki Shiraishi; Toshiomi Kusano; Yoshihiro Muto; Masahiro Higashi

Background/Aims: Radiation-associated rectal cancer is a remarkable clinical entity. We demonstrate 4 patients (mean age 68 years, range 63–74) who had undergone pelvic radiotherapy for cervical cancer. We indicate some characteristics of radiation-associated rectal cancer. Results: Two patients had received intracavitary and external pelvic radiotherapy, while the remaining 2 had external pelvic radiotherapy following hysterectomy. The mean total radiation dose was 63 Gy, though radiation dose information was not available for 1 patient. Colorectal cancer developed at a mean time of 20.7 years (range 11–30) after radiation therapy. All patients presented with chronic radiation colitis, and 3 demonstrated abnormal tumor markers. Colonoscopy revealed an ulcerative, localized well-differentiated adenocarcinoma of the rectosigmoid colon in 1 patient, and diffusely infiltrating cancers of the lower rectum, one signet-ring cell carcinoma and two mucinous carcinomas in the remaining 3. One case was stage I, 2 were stage IIIa, and the remaining case was stage IV. Three patients underwent abdominoperineal resection. The remaining patient was felt to be inoperable. The colorectal wall demonstrated the changes of chronic radiation injury. Two patients died within a short time because of their advanced cancers. Conclusion: Radiation-associated rectal cancer has a tendency to be diagnosed in the advanced stage and to have a poor prognosis. A literature review and our case report suggest that since there are no reliable clinical or laboratory indicators of the presence of a curable colorectal cancer in the setting of chronic radiation proctocolitis, surveillance with a colonoscope should be done 10 years after irradiation in patients with previous pelvic radiotherapy.


Journal of Clinical Gastroenterology | 1997

Clinicopathologic features of resected primary adenosquamous carcinomas of the liver.

Tsutomu Isa; Toshiomi Kusano; Yoshihiro Muto; Masato Furukawa; Masaya Kiyuna; Takayoshi Toda

Four cases of resected adenosquamous carcinoma of the liver were clinicopathologically reviewed, together with immunohistochemical findings. Although no lymph node metastases were seen and a curative resection was achieved in all cases, two patients had recurrences in the peritoneum and distant organs such as the pericardium and pleura relatively soon after the operation. Of the remaining two cases, one patient died during the postoperative period and the other died of coexistent hilar cholangiocarcinoma. Together these findings suggest that this disease tends to spread locally and distantly in the early phase of tumor growth and shows aggressive biological behavior. In an immunohistochemical study, involucrin was a specific marker for the squamous component and CA19-9 was a marker for the adenomatous component.


Surgery Today | 1999

Radiation-associated ischemic coloproctitis: report of two cases.

Hirofumi Tomori; Takashi Yasuda; Masayuki Shiraishi; Tsutomu Isa; Yoshihiro Muto; Haruhiko Egawa

Radiation-associated ischemic coloproctitis is a rare clinical entity caused by vascular insufficiency to the rectosigmoid colon. It most commonly occurs after radiotherapy for gynecological cancer. We present herein the cases of two patients who developed radiation-associated coloproctitis with transmural necrosis and eventual perforation. Perforation of the rectosigmoid colon occurred 3.5 years after radiotherapy in case 1, a 46-year-old woman, and presented as a well-defined small area of transmural necrosis. Conversely, in case 2, a 55-year-old woman, it occurred 1.5 years after radiotherapy, and presented as segmental, diffuse transmural necrosis. The lesion in case 1 had been caused by intramural vascular obliteration due to marked fibrosis of the bowel wall, while that in case 2 had been caused by occlusion of the mesenteric artery with thrombosis. Both patients underwent Hartmann’s resection without rectal excision, and survived the perforative event.


Surgical Laparoscopy Endoscopy & Percutaneous Techniques | 2000

Combined endoscopic and surgical treatment for multiple polyps of the small intestine in Peutz-Jeghers syndrome: a case report.

Kaoru Taira; Hirotaka Matsubara; Tsutomu Isa; Hiroshi Miyazato; Shungo Hiroyasu; Masayuki Shiraishi; Yoshihiro Muto; Fukunori Kinjo

Combined endoscopic and surgical treatment in a 14-year-old girl with Peutz-Jeghers syndrome is reported herein. The patient was diagnosed with Peutz-Jeghers syndrome because of mucocutaneous pigmentation and hamartomas of the small intestine at 10 years of age, when she underwent an emergency laparotomy for an intussusception of the small intestine. Since this diagnosis, she has undergone follow-up, and barium radiologic and endoscopic studies have shown multiple polyps of various sizes from the stomach throughout the small intestine and to the colon. This time, with the use of combined endoscopic and surgical treatment for polyps of the small intestine, 26 polyps were removed endoscopically by performing only one enterotomy. This combined technique may allow for a longer interval between laparotomies, therefore reducing the complications associated with multiple laparotomies and resections.


Journal of Gastroenterology | 1999

Common bile duct blood clot: an unusual cause of ductal filling defects for calculi.

Hideaki Shimoji; Masayuki Shiraishi; Shungo Hiroyasu; Tsutomu Isa; Toshiomi Kusano; Yoshihiro Muto

Abstract: We report a case of obstructive jaundice caused by a blood clot in the common bile duct in a 75-year-old man with cirrhosis. Five years prior to his admission, he had undergone a left hepatectomy for hepatocellular carcinoma. At the present admission, he appeared icteric, and endoscopic retrograde cholangiography revealed filling defects in the common bile duct. Choledochotomy was therefore performed for possible common duct stones, and exploration of the duct showed blood clot casts filling the duct. The casts were easily removed, and the patients postoperative course was uneventful. However, he developed ascites and jaundice 1 month later and died of liver failure approximately 3 months after undergoing the choledochotomy. Autopsy revealed hemorrhagic necrosis in the proximal intrahepatic duct of the posterior segment, which was considered to be the cause of the observed hemobilia, as well as the blood clot in the common bile duct at surgery. We report this rare case and discuss the cause of hemobilia.


Gastric Cancer | 1999

Microsatellite instability in patients with gastric remnant cancer

Atsushi Nakachi; Hiroshi Miyazato; Hideaki Shimoji; Shungo Hiroyasu; Tsutomu Isa; Masayuki Shiraishi; Yoshihiro Muto

Background. About 2% of patients who undergo partial distal gastrectomy for gastroduodenal diseases develop gastric remnant cancer 10 to 30 years after the gastrectomy. It is important in clinical practice to determine a molecular marker to identify patients susceptible to gastric remnant cancer. Methods. We investigated nine gastric remnant cancers (from nine individuals who had gastrectomies for primary gastric cancer or gastroduodenal ulcer) for microsatellite instability (MSI) at six loci, using the polymerase chain reaction (PCR). A control group of ten patients with sporadic gastric cancers in the upper third of the stomach was also similarly analyzed. Results. MSI was demonstrated in eight of nine cancers from the individuals who had had primary gastric cancer or gastroduodenal ulcer (88.9%) compared with two of ten cancers from the individuals with sporadic gastric cancer in the upper third of the stomach (20%). Conclusion. These results suggest that one or more MSI is associated with remnant gastric cancer after gastrectomy.


Clinical Imaging | 2001

Fundic adenomyomatosis bulged with the subserosal excessive fat of the gallbladder mimicking polypoid carcinoma: A case report with unusual imaging and morphological features

Hideaki Shimoji; Atsushi Nakachi; Hirotaka Matsubara; Hiroshi Miyazato; Tsutomu Isa; Shungo Hiroyasu; Masayuki Shiraishi; Yoshihiro Muto

This report describes a 41-year-old female who presented with adenomyomatosis of the gallbladder mimicking polypoid carcinoma, on the diagnostic imaging findings and revealing unusual histologic features for such a localized adenomyomatosis. The mass was located on the gallbladder liver-side wall at the fundus and papillary hyperechoic growth showed no clear ultrasonographic features of adenomyomatosis. The patient underwent a laparoscopic cholecystectomy with a tentative diagnosis of superficial polypoid carcinoma. Histologically, the tumor bulged due to subserosal excessive fat tissue.


Gastric Cancer | 1998

Barrett's adenocarcinoma associated with acquired eventration of the diaphragm.

Hideaki Shimoji; Hiroshi Miyazato; Atsushi Nakachi; Hirotaka Matsubara; Osamu Tamai; Tsutomu Isa; Masayuki Shiraishi; Toshiomi Kusano; Yoshihiro Muto

Abstract:We report a rare case of Barretts adenocarcinoma asso-ciated with acquired eventration of the diaphragm in a 71-year-old woman. She initially developed dysphagia and epigastric discomfort in May, 1997. On July 9, she was referred to our Department of Surgery at the Ryukyus University Hospital for thorough examination and treatment. Esophageal adenocarcinoma and eventration of the diaphragm were revealed by exhaustive examinations, including chest X-ray, computed tomography, and magnetic resonance imaging, and proximal gastrectomy with reconstruction of jejunal interposition was performed, on August 8. Histologically, the tumor revealed that the adenocarcinoma arose from short-segment Barretts esophagus (SSBE). It thus appears that eventration of the diaphragm may induce SSBE and Barretts adenocarcinoma. We therefore recommend that periodic examinations of the esophagus and stomach be performed in patients with eventration of the diaphragm. Barretts adenocarcinoma associated with acquired eventration of the diaphragm is reported. Patients with eventration of the diaphragm should undergo periodic examinations of the esophagus and stomach.

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Yoshihiro Muto

University of the Ryukyus

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Toshiomi Kusano

University of the Ryukyus

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Hideaki Shimoji

University of the Ryukyus

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Atsushi Nakachi

University of the Ryukyus

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Osamu Tamai

University of the Ryukyus

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