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991.
992.
Study Type – Therapy (case series) Level of Evidence 4 What’s known on the subject? and What does the study add? Although extranodal extension in node‐positive patients may provide prognostic information in certain urological malignancies, contradictory results have been reported in node‐positive patients after radical cystectomy for bladder cancer. We examined whether extranodal extension could have an impact on the outcomes of node‐positive patients who underwent radical cystectomy for bladder cancer in a single large tertiary hospital. We have shown that the presence of extranodal extension was not an independent prognostic factor in node‐positive patients after radical cystectomy and pelvic lymphadenectomy for bladder cancer.
OBJECTIVE
? To examine whether extranodal extension (ENE) has an impact on the outcome of node‐positive patients who underwent radical cystectomy for bladder cancer.PATIENTS AND METHODS
? Of 543 consecutive patients who underwent radical cystectomy for urothelial carcinoma of the bladder between 1990 and 2007, 112 patients with lymph node metastasis detected on histological examination were evaluated with regard to recurrence‐free survival (RFS) and disease‐specific survival (DSS) based on ENE status.RESULTS
? The overall 5‐year RFS and DSS rates were 22.3% and 33.8%, respectively. ENE was observed in 41 (36.6%) of the 112 patients. ? The presence of ENE was associated with advanced pathological nodal status (P= 0.004), more positive lymph nodes (P= 0.006), and higher lymph node density (P < 0.001). ? The incidence of positive ENE increased with large positive lymph node diameter (P < 0.001). ? Multivariate analysis showed that lymph node density (hazard ratio (HR) = 2.39, 95% CI 1.09–5.24, P= 0.029; and HR = 3.13, 1.43–6.84, P= 0.004) and use of adjuvant chemotherapy (HR = 1.80, 1.02–3.20, P= 0.041; and HR = 2.07, 1.13–3.79, P= 0.018) were significant predictors of RFS and DSS, respectively. ? After adjustment for other prognostic factors, ENE was not significantly related to RFS (P= 0.825) and DSS (P= 0.961) by multivariate analysis.CONCLUSIONS
? The presence of ENE was not an independent prognostic factor in node‐positive patients after radical cystectomy for bladder cancer. ? Additional prospective studies are needed to determine the independent prognostic role of ENE. 相似文献993.
This retrospective study correlated the mammographic manifestations and averaged nuclear grades using Holland, Van-Nuys, and Lagios classifications in 37 cases of ductal carcinoma in situ (DCIS); microcalcifications alone were seen in 59.4%, microcalcifications with associated mass in 19%, and mass alone in 21.6%. DCIS is more likely to be accompanied by microcalcifications than mass on mammography. Correlation is good between the nuclear grades of DCIS and mammographic manifestations. 相似文献
994.
MRI of primary meningeal tumours in children 总被引:5,自引:0,他引:5
H.-K. Yoon S. S. Kim I. O. Kim D. G. Na H. S. Byun H. J. Shin B. K. Han 《Neuroradiology》1999,41(7):512-516
Childhood meningeal tumours are uncommon and mostly meningiomas. We reviewed the histological and radiological findings in
meningeal tumours in six children aged 12 years or less (four benign meningiomas, one malignant meningioma and one haemangiopericytoma).
Compared to the adult counterpart, childhood meningiomas showed atypical features: cysts, haemorrhage, aggressiveness and
unusual location. MRI features varied according to the site of the tumour, histology, haemorrhage, and presence of intra-
or peritumoral cysts. Diagnosis of the extra-axial tumour was relatively easy in two patients with meningiomas, one malignant
meningioma and one haemangiopericytoma. MRI findings strongly suggested an intra-axial tumour in two patients with benign
meningiomas, because of severe adjacent edema. Awareness of the variable findings of childhood meningiomas and similar tumours
may help in differentiation from brain tumours.
Received: 22 September 1998 Accepted: 18 November 1998 相似文献
995.
The radiographic findings of Pneumocystis carinii pneumonia (PCP) are various. The typical findings are diffuse, bilateral, symmetric, finely granular, or reticular infiltrates.
In patients taking aerosol pentamidine, atypical findings may be the first manifestation. One interesting radiologic finding
of PCP is that the pneumonia may spare the irradiated lung. We report PCP developed in a patient undergoing irradiation for
lung cancer. High-resolution CT revealed diffuse, bilateral, and symmetric ground-glass opacities with septal thickening in
both lungs; however, the radiation port was spared and appeared as the “photographic negative of post-radiation pneumonia.”
The distribution of the pneumonic infiltrates was altered by radiotherapy.
Received: 27 July 1998; Revision received: 23 November 1998; Accepted: 4 January 1999 相似文献
996.
Sung-Hoon Kim Soo-Kyo Chung Yong-Whee Bahk Young-Ha Park Sung-Yong Lee Hyung-Sun Sohn 《European journal of nuclear medicine and molecular imaging》1999,26(2):163-170
The characteristic whole-body and pinhole scintigraphic manifestations of osteo-enthesopathy and arthropathy in Reiter’s
syndrome (RS) are described, with an emphasis on early diagnosis. We analysed 59 sets of whole-body and pinhole bone scintigrams
of 59 patients with RS. The population comprised 47 men and 12 women with an age range from 15 to 53 years (mean=29.4). Bone
scintigraphy was carried out 2–2.5 h after intravenous injection of technetium-99m hydroxydiphosphonate using a single-head
gamma camera (Siemens Orbiter Model 6601) with a low-energy high-resolution and a 4-mm pinhole collimator for whole-body and
pinhole scintigraphy, respectively. In total 262 lesions of osteo-enthesopathy and arthritis were detected on 59 whole-body
scintigrams, an incidence of 4.4 lesions per patient. As anticipated, the lesional distribution was asymmetrical: 68% were
in the lower limb skeleton and 32% in the axial and upper limb skeleton. Pinhole bone scintigraphy, applied selectively to
one region of interest in each case, enabled us to accurately diagnose arthritis and osteo-enthesopathy. It was noteworthy
that osteo-enthesopathy, alone or in combination with arthritis, occurred in 78.9%, and had a strong predilection for the
foot bones, especially the calcaneus (25.6%). Pinhole scintigraphy detected enthesopathy in the absence of radiographic alteration
in 14.1% of cases and portrayed characteristic signs of RS in 6.9%. Whole-body bone scintigraphy augmented with pinhole scintigraphy
was found to be useful in order to panoramically display the systemic involvement pattern, to assess the characteristic bone
and articular alterations and to detect early signs of RS.
Received 1 August and in revised form 17 October 1998 相似文献
997.
Choi D Lee KS Suh GY Kim TS Kwon OJ Rhee CH Han J 《Journal of computer assisted tomography》1999,23(1):107-113
PURPOSE: The purpose of this work was to describe the radiologic findings of pulmonary tuberculosis in patients who presented with acute respiratory failure. METHODS: We included patients who had newly diagnosed active pulmonary tuberculosis and who presented with acute respiratory failure. Initial chest radiographic (n = 17) and high-resolution CT (n = 11) findings of each patient were analyzed retrospectively. RESULTS: Of 1,010 patients with active pulmonary tuberculosis, 17 patients (1.7%) presented with acute respiratory failure. Nine (53%) of the 17 patients died. The most common initial chest radiographic findings were small nodular lesions (16/17; 94%), consolidation (13/17; 76%), and ground-glass opacity (12/17; 70%). Eleven (69%) of 16 nodular lesions, 9 of 13 (69%) consolidations, and 10 of 12 (83%) ground-glass opacities were bilateral. On HRCT (n = 11), miliary micronodular lesions were seen in 6 patients (55%), whereas bronchogenic spread of tuberculosis with disseminated centrilobular nodules and tree-in-bud appearance was seen in 5 patients (45%). Diffuse areas of ground-glass attenuation were seen in all six patients with miliary nodules and four of five patients with bronchogenic spread of tuberculosis. CONCLUSION: Patients with pulmonary tuberculosis occasionally present with acute respiratory failure. In this condition, chest radiograph most commonly shows bilateral small nodular lesions mixed with consolidation or ground-glass opacity, whereas HRCT demonstrates findings of miliary or bronchogenic disseminated tuberculosis with diffuse areas of ground-glass attenuation. 相似文献
998.
Intracranial germinomas: correlation of imaging findings with tumor response to radiation therapy 总被引:9,自引:0,他引:9
OBJECTIVE: The purpose of this study was to correlate imaging characteristics of intracranial germinomas with response to radiation therapy. MATERIALS AND METHODS: Using tumor size at the completion of irradiation, we classified 23 patients with histologically proven germinomas in the pineal gland (n = 6), the suprasellar region (n = 7), and the basal ganglia (n = 10) into two groups: excellent response group (n = 14) and good response group (n = 9). Excellent response was defined as complete resolution or residual tumor less than 1.0 cm in diameter, and good response was defined as residual tumor of 1.0-3.0 cm in diameter. CT (n = 53) and MR (n = 32) images obtained before, during, and after radiation therapy were retrospectively analyzed with particular attention to the location, size, presence of cystic change, and CSF seeding of the tumors. RESULTS: In all 23 patients, the tumors decreased 85-100% in size at the completion of irradiation with 40-56 Gy. A significant factor in the different responses to irradiation between patients in the excellent and good response groups was cystic change of the tumor. Tumors with cystic components responded more slowly and had larger residual lesions than did tumors without cystic components (p < .01). In eight of 12 cystic tumors, the cystic portion of the tumor responded more slowly than did the solid portion and remained visible on imaging 6-12 months after irradiation. We found no significant differences between the two groups in location, size, and CSF seeding of tumors. In 12 patients with residual lesions at the completion of irradiation, the tumors proceeded to resolve after completion of treatment. CONCLUSION: In our study, tumor response to radiation therapy correlated negatively with the presence of a cystic region. 相似文献
999.
Preoperative transarterial embolization of spinal tumor: embolization techniques and results 总被引:6,自引:0,他引:6
Shi HB Suh DC Lee HK Lim SM Kim DH Choi CG Lee CS Rhim SC 《AJNR. American journal of neuroradiology》1999,20(10):2009-2015
BACKGROUND AND PURPOSE: The techniques of preoperative embolization of hypervascular spinal tumors, which has been known to be helpful for completing tumor resection, have not been described in detail. The purpose of this study was to analyze the technique and to evaluate the safety and value of preoperative transarterial embolization of hypervascular spinal tumors. METHODS: Eighteen patients with hypervascular spinal tumors underwent transarterial embolization before surgery. The lesions were located between the upper cervical and lower lumbar spine: C1-T1 (n = 6), T5-L3 (n = 11), and L5 (n = 1); they arose intradurally in six patients and extradurally in 12. Thirty-one arteries were embolized with polyvinyl alcohol (PVA) particles (150-500 microm), and, in 18 of these, pieces of gelatin sponge were added for proximal pedicular embolization. The criteria for judging the effectiveness of embolization were completeness of tumor removal and estimated blood loss during surgery. RESULTS: Tumor embolization was total in eight patients, nearly total in seven, subtotal in one, and partial in two. There were no symptomatic complications associated with embolization. Tumors were totally removed in 17 patients and nearly totally removed in one. The average estimated blood loss during surgery was 1100 mL (range, 200-6000 mL) for all 18 patients, and 1540 mL in patients with extradural tumors. CONCLUSION: Preoperative embolization of hypervascular spinal tumors is safe and effective. It can make complete resection of a tumor possible and can make an unresectable tumor resectable. Superselection or flow control is necessary to achieve effective devascularization and to avoid complications. 相似文献
1000.
Qian Z Maynar M Usón-Garallo J Sanchez-Margallo F Lima-Rodriguez MA Lima-Rodrigues JR Kim JK Gonzalez-Roman A Castañeda WR 《Academic radiology》1999,6(5):317-320
RATIONALE AND OBJECTIVES: The purpose of the study was to evaluate a method of producing obstruction of the common bile duct and concomitant biliary duct dilatation in an animal model. MATERIALS AND METHODS: Laparoscopic placement of a double-balloon occlusion device was used to produce common bile duct obstruction and bile duct dilatation in pigs. RESULTS: One week after the procedure, common bile duct obstruction and dilatation of the biliary tree were demonstrated with either percutaneous transhepatic cholangiography or percutaneous cholecystography. CONCLUSION: The use of this method is technically feasible and provides a useful subacute and chronic animal model of common bile duct obstruction and dilatation of the biliary tree for percutaneous interventional training and research purposes. 相似文献