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Biomedical subjects

Kan Takeda

Publications and source records attributed to Kan Takeda.

At least 73 records · Page 4Linked to original sources

Transluminal stent-graft placements for the treatments of acute onset and chronic aortic dissections.

BACKGROUND: Transluminal stent-graft placement (TSGP) for aortic dissection is a relatively new procedure. We performed TSGPs to seal the primary entry site to treat and prevent complications of aortic dissection. The early to mid-term outcomes were analyzed. METHODS AND RESULTS: Thirty-seven patients with a primary intimal tear in descending aorta underwent TSPG. TSGP was performed in 16 acute onset dissections (AOD) with dissection-related complications instead of emergency surgery. Eight AOD without complications were treated to prevent aneurysmal enlargement. Thirteen chronic dissections were treated to prevent rupture. TSGP was technically successful in all cases. One patient with prehospital rupture died. The hospital mortality rate was of 2.7% overall, 6.3% in AOD with complications, 0% in AOD without complications and in chronic dissections. One persistent endoleak required open surgery, and 1 intimal tear was caused by the stent-graft, necessitating an additional TSGP. The primary success rate was 94.4% overall. After hospital discharge, no patient died or suffered aortic rupture during an average follow-up of 24.5 months. New intimal tears caused by the stent-grafts and a secondary endoleak developed in 3 AOD patients. One open procedure and 2 additional TSGPs were performed. Actuarial survival rate and cardiovascular event-free rate at 2 years are 97.3% and 78.3% overall, 93.8% and 48.0% in AOD with complications, 100% and 87.5% in AOD without complications, and both 100% in chronic dissections. CONCLUSIONS: TSGP is a reasonable treatment option for aortic dissection. However, delayed intimal tear formations caused by the stent-graft is a problem that requires further investigation.

Acute Disease↗

Aortic arch aneurysms: treatment with extraanatomical bypass and endovascular stent-grafting.

Endovascular repair of thoracic aortic aneurysms is emerging as an attractive alternative to surgical graft replacement. However, patients with aortic arch aneurysms are often excluded from the target of endovascular repair because of lack of suitable landing zones, especially at the proximal ones. In this paper we describe our method for treating patients with aortic arch aneurysms using a combination of extraanatomical bypass surgery and endovascular stent-grafting.

Aged↗

DNA ploidy analysis performed prospectively using fresh tumor samples in early glottic carcinoma treated with radiotherapy.

PURPOSE: The correlation between the DNA content, determined using fresh tumor tissues, and the macroscopic presentation of the lesion was studied prospectively in patients with T1 glottic carcinoma. METHODS AND MATERIALS: DNA flow cytometry and fiber-optic endoscopic examination were performed for 30 previously untreated patients with T1 glottic carcinoma. The patients received radical radiotherapy at Aichi Cancer Center Hospital. RESULTS: In regard to the type of lesion, 4 (80%) were aneuploid, and 1 (20%) was diploid for the invasive type. There was a tendency to show an invasive appearance in aneuploid tumors. With respect to clinical outcome, there were 3 (43%) local recurrences among the aneuploid tumors that invaded the entire length of one vocal cord, 0 (0%) for medium-sized lesions, and 1 (17%) for small lesions. Aneuploid tumors showed a high correlation between lesion size and local control. CONCLUSIONS: The correlation was not strong enough to conclude that DNA content can replace the macroscopic presentation of the lesion. However, the combination of DNA content and tumor size may help predict radiation sensitivity.

Adult↗

Arterial chemoinfusion therapy through an implanted port system for patients with unresectable intrahepatic cholangiocarcinoma--initial experience.

Arterial chemoinfusion therapy through an implanted port system was performed for patients with unresectable intrahepatic cholangiocarcinoma (ICC). Eleven patients with unresectable ICC were studied. Seven patients had stage-IV disease, two had stage-III disease, and two had stage-II disease. The mean tumor size was 7.0+/-2.6 cm (range 3.8-13.5 cm). A catheter and port system was percutaneously implanted, and anticancer drugs featuring fluorouracil were administered via the infusion system every 1-2 weeks on the outpatient basis in all patients except 2. Arterial chemoinfusion therapy was repeated 12-84 times per patient (mean 51 times). Partial and minor responses were achieved in sevenents (64%). Disease was stable in two patients (18%), and progressed in the other two patients (18%). Tumor growth was controlled during a mean period of 14.5 months in seven responders and two patients with stable disease. The survival rates were 91% at 1 year, 51% at 2 years, 20% at 3 years, and 10% at 4 years, respectively. The mean survival period was 26 months. Toxicity such as cholangitis and pancytopenia was found in three patients (27%). This treatment seems to improve the prognosis of patients with unresectable ICC and deserves further studies.

Aged↗

Preoperative transcatheter arterial infusion chemotherapy for locally advanced breast cancer (stage IIIb) for down-staging and increase of resectability.

OBJECTIVES: To evaluate the clinical usefulness of preoperative transcatheter arterial infusion chemotherapy (TAIC) for locally advanced breast cancer. METHODS: Seven patients with unresectable locally advanced breast cancer (stage IIIb) underwent TAIC percutaneously 1-3 times (mean, 1.7 times) until tumors became resectable. Anticancer drugs were injected into both the internal mammary and the distal subclavian arteries. RESULTS: There was no major complication related to the procedure. The mean tumor size was significantly decreased from 10.0+/-3.9 to 5.1+/-2.5 cm (P=0.0086). Skin and muscle invasions were improved in two patients (28%) and lymph nodes disappeared in one patient (14%). In two patients (28%), down-staging was achieved from stage IIIb to stage IIIa. All tumors turned into resectable, and mastectomy was performed with a mean period of 35 days (range 9-60 days) after TAIC. Marked decrease in tumor size allowed one patient to receive breast-conserving surgery. There was no local recurrence in any patient. However, five patients (71%) experienced distant metastases. The 3-year disease free and overall survival were 0 and 71.4%, respectively. CONCLUSIONS: TAIC for locally advanced breast cancer is useful in reducing tumor size and achieving down-staging in a relatively short period, leading to an expanded surgical indication.

Adult↗

Aneurysm expansion after stent-graft placement in the absence of endoleak.

Sixty-three patients with thoracic or abdominal aortic aneurysms were treated with endovascular stent-grafts. No endoleak was identified at any interval of follow-up in 58 patients. In four of them (7%), the aneurysms expanded by 10 mm or more during follow-up and additional interventions were required. Aneurysm expansion was caused by inappropriate sealing at the aneurysmal necks in two patients and transgraft seroma in the other two. Although some aneurysm expansion could be avoided by proper patient selection and accurate placement of stent-grafts, it seems difficult to predict aneurysm expansion in most cases.

Aged↗

Radiofrequency ablation combined with chemoembolization in hepatocellular carcinoma: treatment response based on tumor size and morphology.

PURPOSE: To evaluate local therapeutic efficacy of radiofrequency (RF) ablation after chemoembolization for hepatocellular carcinoma (HCC) based on tumor size and morphology. MATERIALS AND METHODS: Sixty-four patients underwent RF ablation under ultrasonographic or real-time computed tomographic (CT) fluoroscopic guidance within 2 weeks after chemoembolization. One hundred eight lesions were treated. Sixty-five lesions were small (<or=3 cm), 32 were intermediate in size (3.1-5 cm), and 11 were large (5.1-12 cm). Seventy-four of the HCCs were nodular lesions and the other 34 were nonnodular (multinodular and infiltrative) lesions. Response to treatment was evaluated by dynamic enhanced CT and magnetic resonance imaging. Tumor necrosis was considered to be complete when no foci of enhancement were seen within the tumor and at its periphery. RESULTS: Complete necrosis was achieved in all lesions regardless of tumor size or morphology. There have been no local recurrences in small and intermediate-sized lesions regardless of tumor morphology during a mean follow-up of 12.5 months. In large HCCs, nodular lesions showed no recurrence, but two of six of nonnodular lesions recurred beyond the thermal lesions created around the tumor. The estimated 1-year survival rate was 98.0% in all patients. CONCLUSIONS: This combined therapy has a therapeutic effect on small and intermediate-sized HCCs regardless of tumor morphology and is a promising treatment option for large nodular lesions. Control of large nonnodular lesions is still a challenging problem.

Adult↗

Refractory biliary leak from intrahepatic biliary-enteric anastomosis treated by selective portal vein embolization.

A 66-year-old woman underwent partial hepatectomy and pylorus-preserving pancreaticoduodenectomy for advanced Klatskin-type cholangiocarcinoma, and five intrahepatic biliary-enteric anastomoses were created. One anastomosis between the anterior-superior segmental bile duct and the jejunum developed a refractory biliary leak. Selective portal venous embolization with use of ethanol was performed in the anterior-superior portal branch to eliminate the production of bile by the target segment. The patient's clinical course was uneventful and the leak resolved after portal vein embolization.

Aged↗

Midterm results of stent-graft repair of acute and chronic aortic dissection with descending tear: the complication-specific approach.

BACKGROUND: Endovascular stent-graft placement for the treatment of patients with aortic dissection is emerging as an attractive alternative to conventional cardiac operations. However, there has been no report of longer-term follow-up. The purpose of this study is to describe our midterm results with endovascular stent-graft repair for the treatment of patients with aortic dissections. METHODS: Thirty-eight patients with aortic dissections with descending tears were treated with endovascular stent-grafting. Ten patients had acute type A, 14 patients had acute type B, and 14 patients had chronic type B dissection. Stent grafts fabricated from expanded polytetrafluoroethylene-covered Z stents were placed to close entry tears in all patients through the delivery systems introduced from the femoral or the iliac arteries. RESULTS: Two patients with complicated acute type B dissection, who would have required surgical intervention, died within 30 days of the procedure, although no other patients died within the same period. There were no late deaths during the mean follow-up period of 27 months. Early and late complication rates were 33% and 36%, respectively, in patients with acute dissection, whereas rates were 4% and 0% (P <.05 vs patients with acute dissection) in patients with chronic dissection. CONCLUSIONS: Entry closure with endovascular stent-graft placement may be a safe and effective method for the treatment of patients with aortic dissection. It could be an alternative to conventional surgical intervention in selected patients with chronic dissection. However, strict patient selection and close follow-up seem mandatory in patients with acute dissection receiving Z stent-based stent-grafts. Stent-graft repair should be delayed for acute type B dissection without complications.

Acute Disease↗

Renal angiomyolipoma: relationships between tumor size, aneurysm formation, and rupture.

PURPOSE: To evaluate the relationships between tumor size, aneurysm formation, and spontaneous rupture in renal angiomyolipomas. MATERIALS AND METHODS: Twenty-three patients with renal angiomyolipoma were examined with angiography and computed tomography (CT). The single largest lesion in each kidney was evaluated. Tumor size was measured at CT, and aneurysm size was measured at renal angiography. Tumor and aneurysm sizes were compared between the group with ruptured angiomyolipoma and the group with unruptured angiomyolipoma. Multiple regression analysis was performed to identify factors affecting rupture. RESULTS: Twenty-nine kidneys with angiomyolipoma were identified. Eight angiomyolipomas were hemorrhagic; the remaining 21 were not hemorrhagic. Tumor size was larger than 4 cm and aneurysm size was 5 mm or larger in all hemorrhagic lesions. There were significant differences in mean tumor size (11.4 cm +/- 5.5 [SD] vs 5.0 cm +/- 3.1, P <.02) and mean aneurysm size (13.3 mm +/- 6.2 vs 2.4 mm +/- 2.9, P <.02) between the ruptured and unruptured tumor groups. When tumor size of 4 cm or larger and aneurysm size of 5 mm or larger were used as predictors of rupture, sensitivity and specificity, respectively, were 100% and 38% with the former criterion and 100% and 86% with the latter criterion. Multiple regression analysis indicated that aneurysm size was the most important factor linked to rupture. CONCLUSION: Aneurysm formation appears to be related to tumor size, and large aneurysms confer a higher probability of rupture.

Adolescent↗

Diagnosis of inflammatory pseudotumor of the liver.

Inflammatory pseudotumor (IPT) is a rare benign tumor of unknown origin, it has the appearance of a malignant tumor but has a benign histology and clinical course. Therefore, we studied five patients with IPT of the liver to determine what examination can aid in its diagnosis. Five cases of inflammatory pseudotumor of the liver were analyzed. All patients were examined by echography, computed tomography (CT), magnetic resonance imaging (MRI), endoscopic retrograde cholangiography (ERC) and angiography to diagnose the liver tumor. In all patients echography and CT scan showed a similar appearance while MRI showed a variable pattern. In two patients ERC showed a stenotic image of intra-hepatic bile ducts. In the angiographic study, the arterial phase in three patients showed a hypervascular tumor and in one patient, a hypovascular tumor. Vascular abnormality was presented in one patient. Similarly, portography in four patients showed some abnormality. We performed ultrasonography-guided percutaneous needle biopsy in two patients in order to diagnose IPT. Histological examinations of two patients were consistent with IPT. The other three patients underwent surgical treatment for a cholangiocellular carcinoma or abscess. It is difficult to diagnose IPT of the liver exclusively with an image examination. Ultrasonography-guided percutaneous liver biopsy should be performed in order to diagnose IPT by histology.

Aged↗

Differences in fatty acid metabolic disorder between ischemic myocardium and doxorubicin-induced myocardial damage: assessment using BMIPP dynamic SPECT with analysis by the Rutland method.

UNLABELLED: Dynamic myocardial SPECT data acquired with 15-(123)I-(p-iodophenyl)-3-(R,S)-methylpentadecanoic acid (BMIPP) were analyzed by the Rutland method. The relative time-activity curves generated from dynamic SPECT in normal control subjects were compared with similar curves from patients with established ischemic heart disease (IHD) and doxorubicin-induced myocardial damage (DxMD). Comparison of such time-activity curves may provide some indirect information concerning qualitative differences in BMIPP metabolism. METHODS: Thirteen patients with various malignancies who received doxorubicin, 16 patients with IHD, and 15 normal control subjects were examined. Immediately after the bolus injection of BMIPP, dynamic data acquisition with a 3-head SPECT system was started and continued for 15 min. Using the time-activity curves of the myocardium as the output function (Mo(t)) and the time-activity curves of the left ventricular cavity as the input function (B(t)), the Rutland equation was calculated: Mo(t)/B(t) = F + K integral B(t)dt/B(t), where F is the blood - background subtraction factor and K is the uptake constant. The duration of the linear portion in this equation and the K values were evaluated. RESULTS: Mo(t)/B(t) was plotted against integral B(t)dt/B(t). Mo(t)/B(t) showed a good linear correlation with integral B(t)dt/B(t) from 30 s to 230 +/- 57 s in normal control subjects. The duration of this linearity was prolonged to 317 +/- 79 s in DxMD (P = 0.0014) and shortened to 182 +/- 58 s in IHD (P = 0.039). The mean K value was 0.0740 +/- 0.0184 in normal control subjects, significantly higher than the K values of 0.0599 +/- 0.0148 in DxMD patients (P = 0.026) and 0.0497 +/- 0.0189 (P = 0.0020) in IHD patients. CONCLUSION: Analysis of BMIPP dynamic SPECT data by the Rutland method is useful for detecting qualitative differences in BMIPP metabolism in various types of myocardial damage. It is speculated that the fatty acid metabolic disorder is characterized by a delay in metabolism in DxMD and by increased backdiffusion in IHD.

Aged↗

Limitations of endovascular treatment with stent-grafts for active mycotic thoracic aortic aneurysm.

An 81-year-old woman with ruptured mycotic thoracic aortic aneurysm was treated with endovascular placement of stent-grafts fabricated from expanded polytetrafluoroethylene and Z-stents. Although exclusion of the aneurysm was achieved at the end of the procedure, a type I endoleak developed on the following day. Despite emergent surgical resection of the aneurysm and extra-anatomical reconstruction, the patient died 2 days later. Stent-graft repair may not be a suitable method for the treatment of ruptured mycotic aneurysm in the presence of active infection.

Aged↗

Dissecting aneurysm of the superior mesenteric artery successfully treated by endovascular stent-graft placement.

Spontaneous and isolated dissecting aneurysm of the superior mesenteric artery is a rare event that has been successfully treated by surgery in several reported cases. To our knowledge, we present the first case of a patient with spontaneous and isolated dissecting aneurysm of the superior mesenteric artery that was successfully treated by endovascular stent-graft placement.

Aortic Dissection↗

Radiofrequency ablation combined with renal arterial embolization for the treatment of unresectable renal cell carcinoma larger than 3.5 cm: initial experience.

The purpose of the study was to evaluate the feasibility, safety, and therapeutic effects of the combination of renal arterial embolization and radiofrequency (RF) ablation to reinforce the anticancer effect on renal cell carcinomas (RCCs) measuring 3.5 cm or larger. This study was undertaken to evaluate this combined therapy on large RCCs-based tumor geometry. Eleven patients with 12 RCCs 3.5 cm or larger in diameter (3.5-9.0 cm) underwent combined therapy. Two were exophytic tumors, and the remaining 10 tumors had components extending into the renal sinus fat. Tumor vessels were selectively embolized in nine patients and the renal artery was completely embolized in two patients with polyvinyl alcohol or ethanol mixed with iodized oil. RF ablation was percutaneously done under the computed tomographic (CT)-fluoroscopic guidance. Response to treatment was evaluated by dynamic contrast-enhanced CT and magnetic resonance (MR) imaging. Tumor enhancement was eliminated after a single RF session in nine tumors (75%), after two sessions in two tumors (17%), and after four sessions in one tumor (8%). Both exophytic tumors (100%) and 7 of 10 tumors having components in the renal sinus fat (70%) were completely ablated with a single RF session. All tumors remained controlled during a mean follow-up period of 13 months and showed significant reduction in tumor sizes (5.2 +/- 1.7 cm to 3.6 +/- 1.4 cm, p < 0.001). A delayed abscess developed in the ablated lesion in a patient, which was percutaneously drainaged. Combined therapy as described in this report is a feasible, relatively safe, and promising treatment method for large RCCs regardless of tumor geometry.

Adult↗