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Biomedical subjects

Masaki Kitajima

Publications and source records attributed to Masaki Kitajima.

At least 73 records · Page 4Linked to original sources

Morphologic analysis of gastroesophageal reflux diseases in patients after distal gastrectomy.

The precise mechanisms that cause gastroesophageal reflux after distal gastrectomy remain unclear. We analyzed the endoscopic findings of the cardia and the position of the remnant stomach, which are related to gastroesophageal reflux. We retrospectively examined the records of 45 patients with Billroth I (B-I) and 39 patients with Roux-en-Y (R-Y) procedure for gastric cancer. Esophagitis was evaluated by the Los Angeles (LA) classification. The endoscopic findings of hiatus hernia were classified according to the criteria of the Keio Cancer Detection Center form (K-form). The valvular appearance of the cardia was classified according to V-grades. The height of the remnant stomach was measured on computed tomography scans. The postoperative findings of esophagitis in the B-I group were significantly worse than the preoperative findings, but no significant change was observed in the R-Y group. The postoperative V-grades and K-forrn findings in the B-I group were worse than their preoperative findings. In the R-Y group, however, there was no significant change in the V-grades or K-form findings. In addition, the height of the remnant stomach was significantly higher in the B-I group than in the R-Y group. This study suggested that an aggravated cardia is associated with the B-I procedure and that the position of the remnant stomach may therefore play an important role in the occurrence of postoperative reflux esophagitis. In contrast, the R-Y operation was shown to preserve the cardia and the position of the remnant stomach better. As a result, R-Y might help prevent not only duodenogastric reflux but also gastroesophageal reflux.

Adult↗

Gallstone disease after extended (D2) lymph node dissection for gastric cancer.

Few studies have reported the incidence and clinical outcomes of gallstone disease after extended (D2) lymph node dissection for gastric cancer. The present study was designed to retrospectively compare limited (D1) and D2 dissections in terms of gallstone formation, presentation of gallstones, and surgery for gallstone disease. A total of 805 Japanese gastric cancer patients (595 male, 210 female) who underwent curative resection with D1 (n = 490) or D2 (n = 315) dissection were retrospectively reviewed. Of those subjects followed for 70.5 +/- 44.3 months (range: 2-196 months), 102 (12.7%) developed gallstones. The incidence of gallstone formation was higher in the D2 group than in the D1 group (17.8% vs. 9.4%, p = 0.001). The interval between gastrectomy and detection of gallstones was shorter in the D2 group than in the Dl group (18.8 +/- 11.4 months vs. 29.4 +/- 18.3 months, p = 0.002). Of those with gallstones followed for 48.0 +/- 28.6 months (range: 1-158 months), 74 (72.5%) remained asymptomatic, and 15 (14.7%) experienced mild biliary pain. Thirteen patients (12.7%) developed recurrent biliary pain (n = 3) or biliary complications (n = 10; 6 acute cholecystitis, 3 obstructive jaundice, and 1 cholangitis), and required surgical treatment. Surgery was more frequently sought in the D2 group than in the D1 group (19.5% vs. 4.3%, p = 0.033). In conclusion, patients with D2 dissection developed gallstones more frequently and earlier than patients with D1 dissection. Of those with gallstones, patients with D2 dissection required surgery more often than patients with D1 dissection. A closer follow-up should be mandatory for gallstone disease after D2 dissection, but further studies are needed before generalizations can be made.

Aged↗

Long-term survival of patients with gallbladder cancer detected during or after laparoscopic cholecystectomy.

Little evidence is available regarding long-term survival of patients with gallbladder cancer that is discovered at the time of laparoscopic cholecystectomy (LC). Therefore the present study was performed to evaluate long-term outcomes of this disease. Of 1546 patients who underwent LC for benign gallbladder disease between January 1992 and January 2002, 8 patients (0.5%) had cancers that were found during or after LC. The median follow-up period was 55 months (range: 36-142 months). The gallbladder was resected without perforation in all cases. During surgery there was a suspicion of malignancy in 6 of 8 cases. Frozen section analysis showed that 2 had TNM stage Tis tumors, 2 had T1a tumors, and 2 had T2 tumors. Two patients with T2 tumors were immediately converted to extended cholecystectomy. The final pathology revealed another 2 tumors, and demonstrated that 3 patients had Tis tumors, 3 had T1a tumors, and 2 had T2N0M0 tumors. None of the patients underwent additional surgery. All patients survived with no evidence of recurrence during the median follow-up of 55 months. In conclusion, before and during LC, we have not overlooked T2 or more advanced tumor, which requires additional procedures for curative resection. This might result in good survival. We consider that an intensive preoperative work-up and meticulous inspection of the opened gallbladder should be mandatory to detect gallbladder cancer in patients who undergo LC. At present, this is not routinely practiced.

Adult↗

Left trisegmentectomy and combined resection of the inferior vena cava, without reconstruction, for giant cystadenocarcinoma of the liver.

A 54-year-old woman with giant liver cystadenocarcinoma underwent left trisegmentectomy with combined resection of the inferior vena cava (IVC) and the right hepatic vein. As a result, only the right inferior hepatic vein was preserved as a drainage vein. Because the perivertebral plexus and the azygos vein were both well developed, neither veno-venous bypass nor IVC reconstruction was performed. The developed collateral veins acted as the venous drainage pathway to maintain a stable systemic circulation. On the seventh postoperative day, portal vein flow dramatically decreased and the patient tended to liver failure. Prostaglandin E(1) (PGE(1)) was administrated via the superior mesenteric artery. The portal flow then gradually increased and liver failure was avoided. Six months after the operation, she was re-admitted due to obstructive jaundice and presented with complete stenosis of the common bile duct (CBD). The jaundice persisted and liver dysfunction progressed. The patient died seven months after the operation. The confluence of the right inferior vein and the IVC could have been deformed, causing outflow blockade. The intrinsic shunt was not good enough to act as the drainage pathway, and IVC reconstruction may have been needed.

Cystadenocarcinoma↗

Primary undifferentiated spindle-cell carcinoma of the gallbladder presenting as a liver tumor.

Undifferentiated spindle-cell carcinoma (SpCC) of the gallbladder is extremely rare. There is very little information available regarding the characteristics and treatment of this disease. We herein report the unique case of a 76-year-old female patient with a primary SpCC of the gallbladder that presented as a liver tumor. Preoperative radiologic examinations showed a 5-cm liver tumor around the gallbladder bed, and irregular thickening of the gallbladder wall. The patient underwent en-bloc resection of the gallbladder and segments 4b and 5 of the liver (including the liver tumor). Microscopic findings revealed that both lesions consisted mainly of a sarcomatous spindle-shaped component. Small foci of well-differentiated adenocarcinoma cells were identified in the gallbladder mucosa. There was a gradual transition between the two different components, thereby implying that these two cell types had a common origin. Immunohistochemical studies showed that the spindle-shaped cells were epithelial in nature. The patient's postoperative course was uneventful. However, she died of recurrent liver disease 6 months after the surgery. In conclusion, we surmised that the sarcomatous spindle cells originated from a carcinomatous component in the gallbladder mucosa through dedifferentiation. Further studies are needed to better understand the characteristics of this deadly tumor, and to establish an effective therapy for it.

Adenocarcinoma↗

Minimally invasive surgery for gastric cancer--toward a confluence of two major streams: a review.

The minimalization of therapeutic invasiveness in order to preserve quality of life (QOL) is a major topic in the management of early gastric cancer. After laparoscopic surgery for gastric cancer was introduced by Kitano et al. in 1991, an enthusiasm to develop laparoscopic procedures has grown steadily. In the initial phase, early gastric cancer limited to the mucosal layer with no risk of lymph node metastasis was treated by laparoscopic wedge resection or intragastric mucosal resection. Since technical and instrumental advances in endoscopic treatment were achieved by gastroenterologists, these cases can be managed by intraluminal endoscopic approaches. The attention of surgeons then shifted to more radical procedures such as laparoscopic gastrectomy with lymph node dissection, which is comparable to open surgery and can be indicated even in advanced cancer. Although this paradigm shift has already been realized in the field of colorectal surgery, we must pay attention to the particular biological nature of gastric cancer in terms of the potential of peritoneal dissemination. While early-phase recovery after surgery has been improved by laparoscopic surgery, preservation of late-phase QOL by function-preserving surgery is also essential in this regard; therefore, the sentinel node (SN) concept has been a much-discussed topic in gastric cancer surgery to approach this aspect. Recently, the validity of the SN concept has been demonstrated by a number of single institutional studies, and prospective multicenter trials are currently ongoing. Theoretically, various types of function-preserving surgery could be applied in cases of early gastric cancer with negative SNs as less invasive surgery to improve long-term QOL. Although we still have to solve several remaining issues in the treatment of gastric cancers, a confluence of these two major streams, laparoscopic surgery and sentinel node navigation surgery, would enable us to apply a novel individualized minimally invasive approach, both in terms of degree of incisional access and extent of function preservation.

Gastrectomy↗

Partial resection of the second portion of the duodenum for gastrointestinal stromal tumor after effective transarterial embolization.

We report herein the case of 64-year-old man with gastrointestinal stromal tumor (GIST), who was treated by partial resection of the duodenum after preoperative transarterial embolization. He presented to our hospital with a history of tarry stools, dizziness, and severe anemia (hemoglobin, 7.5 g/dl). Gastroduodenal endoscopy revealed the presence of a submucosal tumor in the second portion of the duodenum. The presence of the tumor was subsequently confirmed by double-contrast gastrointestinal radiography and abdominal computed tomography. Super-selective angiography showed tumor staining fed from the anterior and posterior superior pancreaticoduodenal arteries, and the inferior pancreaticoduodenal artery. Two weeks after transarterial embolization through these vessels, the tumor size was found to have shrunk to 40% of its original size. Partial resection of the duodenum was performed and absence of tumor cells at the surgical margin was confirmed by intraoperative frozen-section examination. Histopathological examination revealed that the duodenal submucosal tumor consisted of spindle cells, and immunohistochemical analysis revealed positive tumor staining for c-kit protein, CD34 and alpha-smooth muscle actin (SMA), and negative staining for desmin and S-100; the positivity rate for MIB-1 staining was 2.2%. Based on these findings, the tumor was diagnosed as a GIST of low-grade malignancy, classified as the muscular type. It is considered that preoperative treatment of duodenal GISTs, such as transarterial embolization, may be useful for reducing the extent of resection, from pancreaticoduodenenctomy to a partial resection.

Duodenal Neoplasms↗

Surgical site infection surveillance after open gastrectomy and risk factors for surgical site infection.

Surgical site infection (SSI) surveillance was examined in gastric cancer patients who had undergone an open gastrectomy between 1997 and 2003 at Keio University Hospital in Tokyo, Japan. National Nosocomial Infections Surveillance (NNIS) reports and several studies have discussed SSI risk factors, but only open gastrectomy was analyzed by regression analysis. The purpose of this study was to examine these issues by performing a regression analysis for the prediction of SSI. SSI was defined by the surgical patient component according to the NNIS system (1999) produced by the Centers for Disease Control and Prevention. Patients undergoing an open gastrectomy were followed up and monitored for SSIs. Risk factors for SSI, after all factors were considered, were studied using single and multivariate analysis. The study enrolled 984 patients who had undergoing an open gastrectomy. Using multivariate and logistic regression analysis, the duration of the operation was identified as a [corrected] risk factor for SSI at open gastrectomy. Although numerous potential risk factors in surgical patients were examined, the duration of the operation was the only significant risk factor for SSIs after open gastrectomy.

Aged↗

Increasing age does not affect efficacy of sentinel lymph node biopsy using smaller-sized technetium-99m tin colloids for breast cancer patients.

BACKGROUND: Increasing age of breast cancer patients was reported to cause not only failure of sentinel lymph node (SLN) identification but also false negative results. METHODS: A retrospective review was conducted of breast cancer patients who underwent sentinel lymph node biopsy (SLNB) using small-sized technetium-99m-labeled tin colloid (particle size: 200-400 nm in diameter). A comparison between 82 patients who were less than 60 years and 40 patients who were > or =60 years of age was performed to evaluate the efficacy of SLNB using the small-sized tin colloid in older patients. RESULTS: One hundred twenty-two clinically node-negative breast cancer patients underwent SLNB. Apart from age, there were no statistically significant differences between the younger patients and the older patients in terms of the clinicopathologic characteristics. Successful mapping rates, false negative rates, and accuracy were comparable between the 2 groups. CONCLUSIONS: SLNB using the small-sized tin colloid was not affected by increasing age.

Adult↗

Selective cyclooxygenase 2 inhibitor induces indefinite survival of fully allogeneic cardiac grafts and generates CD4+ regulatory cells.

BACKGROUND: Selective inhibition of cyclooxygenase 2 has been reported to have not only anti-inflammatory effects but also effects on the immune response. We investigated ability of a cyclooxygenase 2 inhibitor to inhibit alloimmune response in a murine cardiac transplantation model. METHODS: CBA (H2(k)) mice underwent transplantation of C57BL/10 (H2(b)) hearts. On the day of transplantation, the recipients received either no treatment or single administration of aspirin (a cyclooxygenase 1 and 2 inhibitor) or the selective cyclooxygenase 2 inhibitor NS-398. Naive CBA mice (secondary recipients) underwent adoptive transfer of splenocytes from treated mice with long-surviving grafts (primary recipients) to determine whether regulatory cells developed after NS-398 treatment. Histologic, cell-proliferation, and cytokine studies were also performed. RESULTS: Untreated CBA mice rejected C57BL/10 cardiac grafts acutely (median survival time, 8 days). The majority of recipients given aspirin rejected their grafts within 20 days (median survival time, 11 days). In mice given NS-398, the majority of the grafts survived indefinitely (median survival time, >100 days). Secondary CBA recipients given CD4+ splenocytes from primary CBA recipients treated with NS-398 also had indefinite survival of C57BL/10 hearts (median survival time, >60 days). Graft acceptance and proliferative hyporesponsiveness were also confirmed by the histologic and cell-proliferation studies, respectively. Production of interleukin 4 and 10 from splenocytes of the recipients treated with NS-398 were significantly higher than that from untreated recipients. CONCLUSIONS: In our model administration of cyclooxygenase 2 inhibitor induced indefinite survival of fully mismatched cardiac grafts and generated CD4+ regulatory cells. Cyclooxygenase 2 inhibitor could warrant consideration for use as an immunomodulating agent in clinical transplantation.

Animals↗

Gastric cancer mimicking a submucosal tumor diagnosed by laparoscopic excision biopsy.

We report a case of advanced gastric cancer exhibiting the features of a submucosal tumor (SMT) of the gastric body. The patient was a 50-year-old male in whom a gastric SMT was detected during a mass screening examination. Upper gastrointestinal endoscopy revealed a protuberant tumor, 2 cm in diameter, covered with normal-appearing mucosa. Examination of an endoscopic biopsy specimen of the tumor revealed chronic gastritis with regenerative and erosive changes. An endoscopic ultrasound examination demonstrated a hypoechoic mass in the third layer of the gastric wall. The clinical diagnosis was gastric SMT, and the patient's course was monitored. Twenty-six months after the initial visit to our hospital, an endosonograph-guided biopsy revealed Group III (borderline lesion). Three months after the biopsy, the size of the SMT had increased slightly. Laparoscopic wedge resection of the tumor was performed to make a pathologic diagnosis and we were able to make a diagnosis of gastric lymphoepithelioma-like carcinoma intraoperatively. Gastrectomy with lymph node dissection was followed as curative surgery. Laparoscopic total excision biopsy is a useful technique in patients with a gastric SMT whose diagnosis has not been confirmed pathologically.

Biopsy↗

Value of computed tomography-derived estimated liver volume/standard liver volume ratio for predicting the prognosis of adult fulminant hepatic failure in Japan.

BACKGROUND AND AIMS: The prognosis of fulminant hepatic failure (FHF) has been improved but is still unsatisfactory, and liver atrophy has been reported as a poor prognostic factor for this disease. The aim of this study was to assess the clinical value of the estimated liver volume (ELV) compared to the standard liver volume (SLV) in patients with FHF. METHODS: Estimated liver volume of 24 adult patients with FHF receiving artificial liver support (ALS) was measured by using computed tomography. Actual liver weight (ALW) was measured if possible, and the calculated ELV/SLV ratio was compared to the ALW/SLV ratio and the ALW/BW (bodyweight) ratio. Sequential ELV/SLV ratios during the clinical course were analyzed in relation to the prognosis. RESULTS: The ELV/SLV ratio was significantly correlated with both the ALW/SLV and ALW/BW ratios. The mean ALW/SLV ratio of patients who underwent living donor liver transplantation (LDLT) was 0.59 +/- 0.17. The mean ELV/SLV ratio at the time of starting ALS (day 0) in the patients who survived (group 1) was 1.081 +/- 0.183, but that of cases who underwent LDLT or died without LDLT (group 2) was 0.764 +/- 0.255. The mean ELV/SLV ratios were 1.084 +/- 0.222 and 0.650 +/- 0.195 in groups 1 and 2, respectively, 5 days after starting ALS (day 5). Among the group 2 patients, those who had no liver atrophy on day 0 had a significantly decreased ELV/SLV ratio on day 5. CONCLUSIONS: These results suggest that the ELV/SLV ratio is a very useful objective marker to estimate liver atrophy and this marker reflects the prognosis of FHF patients very well.

Adult↗