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1.
Cellular levels of O6-methylguanine-DNA methyltransferase (MGMT) correlate strongly with cellular resistance to carcinogenic and chemotherapeutic agents that produce adducts at the O6-position of guanine in DNA. Although biochemical and molecular assays can indicate the average MGMT content of tissues or tumors, they cannot distinguish mixed populations of cells, such as those that exist in tumor biopsy samples. We have determined MGMT at the cellular level in a panel of pediatric rhabdomyosarcoma xenografts by in situ immunostaining with a human MGMT-specific antibody employing a very sensitive procedure that involves biotin-avidin coupled horseradish peroxidase with silver-enhanced diaminobenzidine-nickel staining. Two xenograft tumor lines known to be MGMT-deficient were not stained, whereas the nuclei in three MGMT-expressing lines were clearly stained. This is the first demonstration of an in situ procedure that discriminates drug-sensitive MGMT-deficient tumors from drug-resistant MGMT expressing tumors. This procedure should prove useful, therefore, for predicting the susceptibility of tissues and tumors to O6-guanine alkylating agents.  相似文献   

2.
The dexamethasone-modified adrenal scintiscan, a noninvasive procedure, is described for the preoperative distinction between primary aldosteronism (aldosterone-producing ademona) and idiopathic aldosteronism (bilateral hyperplasia) and for the preoperative localization of aldostersone-producing adenomas. This procedure has been carried out on 17 subsequently proved cases of primary aldosteronism and nine cases (four unexplored) of idiopathic aldosteronism. In the tumor cases, it indicated correctly the side of the tumor in 88 per cent. It was correct in predicting the existence of bilateral hyperplasia in all of the five cases explored. It produced the same response in four more cases believed to have bilateral hyperplasia, in which surgical exploration has not been carried out. Many of the same patients had, in addition, standard adrenal scintiscans (SS), adrenal venography, and determinations of aldosterone in adrenal venous blood. These results are compared with those of the dexamethasone scintiscan (DS). In tumor localization, the 88 per cent figure for the DS was only moderately better than that of the other three (71 per cent, SS; 80 per cent, venography; 80 per cent, adrenal venous aldosterone levels). However, in predicting bilateral hyperplasia, the DS was 100 per cent correct, as were the levels of aldosterone in adrenal venous blood. The SS and adrenal venography failed in bilateral hyperplasia and gave many false-positive results indicating tumor. The DS, a relatively simple outpatient procedure, appears to be at least as effective, both in lateralizing tumors and distinguishing between tumor and bilateral hyperplasia, as the more difficult, expensive, and sometimes hazardous invasive procedure of bilateral adrenal vein catheterization.  相似文献   

3.
For localized, non-small cell carcinomas (stages I and II) surgery is the treatment of choice because these lesions usually can be excised completely. The choice of the surgical procedure--lobectomy, pneumonectomy, segmental or sleeve resection--depends on the extent of malignant disease and the patients functional status. The procedure of choice is usually that which will encompass all existing disease and provide maximum conservation of normal lung tissue. On occasion, stage III disease may present borderline cases for surgery. Indications are based on existing or imminent complications in advanced locoregional tumor growth. Localized chest-wall or pericardium invasion, superior sulcus tumors, limited mediastinal nodal involvement, and phrenic involvement are not absolute surgical contraindications. Each case must carefully be evaluated and individualised. This kind of tumor management requires sophisticated techniques. The primary aim is to achieve complete tumor resection and to avoid an exploratory thoracotomy or an incomplete surgical resection. The hilar and mediastinal lymph nodes have to be completely resected to ensure a real R0-resection. The presence of distant or extrathoracic metastasis is indicative of inoperability and a surgical procedure is an absolute contraindication. There is no proven place to date for debulking surgical procedures in lung cancer.  相似文献   

4.
Computed tomography assesses the linear coefficient of X-ray radiation decrease in the tissue and hence determines changes in its density thus allowing one to control the destruction of tumor cells and tissues during treatment. The paper proposes a procedure for determining the sizes and density of a tumor along the chosen linear direction crossing the image of a pathological focus. The whole procedure is performed by the special computer programme "Diaglmag". The equations that characterize the dynamics of using the parameters used before, during, and after treatment are presented. Baseline information on the optic image densities on a computer tomogram is obtained with a graphic scanner. The examples presented in the paper show it feasible to solve a difficult task to determine the effect of treatment. This enables a treatment regimen to be corrected in time or modified.  相似文献   

5.
We have performed thoracoscopic resection of schwannoma without intraspinal extension in two asymptomatic cases confirmed by chest roentgenogram and computed tomography: the case 1 with the tumor as large as 4.0 x 4.0 x 3.5 cm found in the paravertebral fifth Intercostal space, the case 2 with the tumor as large as 3.2 x 2.5 x 1.8 cm found on the first rib in contact with the supreme intercostal vein. In the operation of case 1, the dilated fifth intercostal vein in contact with the tumor which could not be controlled by Endo-Clip was doubly ligated by the use of Knot-Pusher. The tumor was successfully dissected from the chest wall and proved to arise from the fifth intercostal nerve. The tumor was brought into Endo-Pouch and extracted through one of the skin incisions which was minimally enlarged to accommodate the pouched lesion. In the operation of case 2, curved forceps facilitated the procedure because the tumor located near the apex of thorax. The tumor was found to originate from sympathetic nerve and removed through the minimally enlarged incision as case 1. We conclude as the following. The benign tumor found in the mediastinum or the chest wall is amenable to thoracoscopic treatment. In thoracoscopic procedure, as the operation under thoracotomy, we must acquire skills of standard operative technique, i.e., suture or ligation, because those skills are necessary when Endo-Clip or Endo-GIA cannot be used. The skin incision should be minimally enlarged finally when the specimen is extracted to minimize operative intervention.  相似文献   

6.
Intraluminal ultrasound with 12.5 and 20 MHz transducer allows precise analysis of the extrahepatic bile ducts and the adjacent structures. Inflammatory and malignant thickening of the bile duct wall can be assessed without difficulty. It is not possible, however, to differentiate between benign and malignant bile duct thickening, and for this purpose biopsy is required in addition. In tumor staging intraluminal ultrasound is superior to conventional ultrasound, because tumor infiltration into the adjacent tissues can be assessed and lymph nodes along the hepaticoduodenal ligament can be detected. Owing to the ultrasound frequencies available, local staging is limited to a circumference of 1.5/2 cm. Intraluminal ultrasound provides additional information that is useful in the diagnosis and therapy of bile duct stones and in different types of palliative tumor therapy. The procedure is simple and not too time consuming, and it involves no risks to the patient.  相似文献   

7.
Concerning laparoscopy and tumor dissemination, we know from several multivariate analyses that at laparotomy, if the tumor is entirely and immediately removed, the puncture of a stage I ovarian cancer has no influence on the prognosis. In contrast the inadequate surgical management of an undiagnosed ovarian cancer may worsen the prognosis. The diagnosis is the key step. To be able to immediately and completely treat an ovarian cancer when managing an ovarian tumor surgically, Laparoscopic diagnosis is safe and reliable when used cautiously. The surgical diagnosis may and should probably be performed by laparoscopy whatever the ultrasonographic appearance of the tumor. Masses diagnosed as suspicious at surgery should be treated by immediate laparotomy, since the results of laparoscopic treatment of an ovarian cancer are not known. In young patients, conservative surgery is the main advantage of laparoscopy, and should be achieved in most benign masses. The recent progresses of in vitro fertilization should be taken into account when managing an ovarian tumor in a patient who wishes to become pregnant. Frozen sections are useful, when treating highly suspicious masses, allowing an immediate staging and avoiding the disadvantages of a second surgical procedure. Whenever a malignant tumor has been missed at laparoscopy, restaging is required and should be considered to be an oncologic emergency.  相似文献   

8.
BACKGROUND: Primary tumors of the vertebral bodies have previously been treated with total or subtotal excision in a piecemeal fashion (intralesional excision). Radiation therapy has been used to help control tumor growth. Recurrence rates with an intralesional, piecemeal removal of vertebral tumors have been unacceptably high. This study describes a method to excise a lumbar vertebra "en-bloc," and in the process, to perform a marginal (extralesional) resection of a primary tumor of the mobile lumbar spine that allows for a potential surgical cure. METHODS: A combined posterior-anterior procedure allows for an extralesional, marginal resection of the tumor and the involved vertebra. All posterior bony elements, including the pedicles and the adjacent intervertebral discs, are removed via a posterior approach. An anterior, retroperitoneal approach is then used to remove the vertebral body/tumor as a single specimen. The nerve roots at the involved levels are spared and the spine is instrumented and fused both posteriorly and anteriorly. RESULTS: Three patients successfully had combined posterior-anterior resections of lumbar vertebral chordomas. No permanent neurological complications occurred. Overall morbidity of the procedure was acceptable. At 31-month follow-up, no tumor recurrence has been detected. CONCLUSIONS: "En-bloc" resection of a primary vertebral tumor of the lumbar spine is technically demanding, but potentially curative. The alternative approaches-intralesional excision, radiation therapy, or a combination-are unable to cure these tumors. Long-term, 10-year follow-up will be necessary to confirm whether this en-bloc approach provides a surgical cure.  相似文献   

9.
Residual tumor volume has been considered important in predicting survival following brain surgery. The purpose of this study was to develop a procedure for quantifying pre- and postsurgical brain tumor volumes that is less subjective than the traditional qualitative grading scale still used by surgeons and radiologists to assess extent of resection (such as gross total, subtotal, and partial resection). Pre- and postsurgical magnetic resonance (MR) imaging brain scans on GE Medical System optical disks were transferred to a Macintosh personal computer using a Pioneer optical disk drive subsystem, and the MedVision 1.41 computer software program was used to analyze regions of interest (ROIs) within them for computation of the volume of tumor tissue therein. Because this procedure puts the original MRI (or CT scan) data file for a patient directly into the personal computer, it bypasses the need for scanning and digitizing MR (or CT scan) film images. Between June 1993 and May 1996, pre- and postsurgical volumetric measurements were made in more than 1,000 brain tumor resection cases and 49 radiosurgery cases. The average intra-observer error was estimated to be 1.8%. This method should facilitate the examination of the effects of various therapies on extent of brain tumor resection. The method is fast, is more precise than intraoperative visual assessment of tumor removal or qualitative comparison of pre- and postoperative scans, and it allows the computation of pre- and postsurgical (three-dimensional) volumes of even irregularly shaped tumors.  相似文献   

10.
The major prerequisite for resection of a pancreatic tumor is non-involvement of large blood vessels. Preoperative assessment of blood vessel infiltration may prevent unnecessary surgery. The aim of our study was to investigate the accuracy of endoscopic ultrasonography (EUS) in diagnosis of pancreatic cancer and in preoperative staging. Thirteen patients (7 females, 6 males; mean age 64 years) with a pancreatic tumor, but no evidence of distant metastases, underwent EUS and computerized tomography (CT) in order to assess blood vessel involvement by the tumor. The results were compared with intraoperative findings in 12 patients and with postmortem findings in 1 patient. A tumor was demonstrated by EUS in 12 patients and was confirmed at surgery in all 12 patients. In one patient no tumor was demonstrated by EUS, although a tumor was visible by CT; no tumor was found at surgery. In two patients CT failed to demonstrate a pancreatic tumor that was demonstrated by EUS; at surgery a tumor was detected in both patients. EUS detected blood vessel involvement in seven patients, which was confirmed at surgery in six of them. In the other six patients surgery confirmed the EUS finding of no blood vessel involvement. CT detected blood vessel involvement in two patients only. The overall accuracy of EUS and CT for detecting the tumor was 100% and 77% respectively, and for blood vessel involvement 92% and 61% respectively. In conclusion, EUS is an accurate procedure for preoperative assessment of blood vessel involvement in patients with pancreatic cancer. This procedure may enable the selection of those patients who may benefit from surgery, and should be part of the evaluation of patients with pancreatic cancer who are candidates for curative surgery.  相似文献   

11.
Earlier studies have suggested that a solid tumor behaves, in its general pattern of growth, like a normal integrated organ. In this study, the growth patterns of spherically shaped tumor nodules are re-examined using an accurate tumor volume-measuring procedure, with the aim of investigating the possible role of apoptosis in regulating tumor growth. Observations revealed at least three distinct phases of growth: rapid growth phase I, slower growth phase II and 'stationary' phase III. Transition from one phase to the next was primarily due to an increase in the level of apoptosis and not to a decrease in the cell proliferation rate. The level of apoptosis, at a given phase, was similar in a single nodule and each of the multiple coexisting nodules of the same tumor line. However, temporal shifts in apoptosis levels caused early phase transition in coexisting nodules, such that their total volume was the same as that of a single nodule. It can be concluded that apoptosis appears to be a primary mechanism regulating tumor growth as a 'total mass', irrespective of whether the tumor exists in one or multiple nodules, if derived from the same tumor line.  相似文献   

12.
The majority of patients with soft tissue or bone sarcomas of the upper extremity can be treated today with limb-saving procedures using combined modality therapies. For patients with a tumor in the shoulder area, sometimes an interscapulothoracic amputation is the only radical surgical treatment. However, in selected cases, in which the tumor does not involve the neurovascular bundle, a limb-sparing alternative might be the Tikhoff-Linberg resection. Normal function of the hand and forearm, with reasonable function of the elbow, can be maintained by this procedure. Four case histories are reported.  相似文献   

13.
14.
OBJECTIVE: Failure to diagnose synchronous tumors leads to errors in patient treatment and prognosis. The existence of metachronous tumors requires strict patient follow-up to ensure early identification of the second tumor. The present study evaluates the results obtained in the application of a structured procedure for the diagnosis and follow-up of multiple colorectal carcinoma. MATERIALS AND METHODS: A structured procedure was used to follow for 5 years a group of 12 patients with multiple colorectal tumors (7 synchronous and 5 metachronous) of a series of 450 colorectal neoplasms. RESULTS: Six synchronous tumors were diagnosed preoperatively and one intraoperative. Of the 5 metachronous neoplasms, 4 strictly adhered to the follow-up protocol, as a result of which the second tumor was detected at an early stage. The remaining case involved no follow-up, and the second tumor was diagnosed in an advanced stage as a result of bowel occlusion. The left colon was predominantly involved; polyps were detected in 9 cases, while two patients had 3 malignancies detected by histopathological study. COMMENTS: We emphasize the need for a full evaluation of the colon in all patients with colorectal carcinoma. In the case of incomplete preoperative evaluation, intraoperative colonoscopy is to be considered; if this is not feasible it should be performed one month after surgery. A structured follow-up procedure permits the early detection of these tumors, there by improving patient prognosis.  相似文献   

15.
PURPOSE OF STUDY: The surgical and clinical outcome of a limb-salvaging technique for tumors about the knee utilizing autogenous vessel transfer is reported. The original indication for these lesions was amputation or Van Nes rotationplasty because of vascular encasement by the tumor. MATERIAL: Twelve patients are reported: seven females and five males with an average age of 16 years. There were nine distal femur and three proximal fibula stage IIB primary malignant tumors. METHOD: All patients underwent a local wide resection of the primary tumor including the main vessels, followed by local reconstruction of the bone and vessels by an ipsilateral vessel transfer. Postoperatively the limbs were immobilized in a cast and the patients were treated with intravenous Heparin, followed by a single low dose Heparin injection for three months. RESULTS: Immediate postoperative arterial occlusion in one patient was successfully treated, but eight weeks later another occlusion occurred and an amputation was necessary. In another patient, arterial thrombi necrotized two toes; they were subsequently amputated. Other local complications were hematoma (two patients), superficial skin necrosis (one patient), and deep infection (one patient). All were successfully revised surgically. All resections obtained negative margins, and there were no local recurrences or distant metastases. In all twelve patients the tumor either encased the artery and vein, or the pseudocapsule of the tumor touched the vascular adventitia. DISCUSSION: The results show that by patients in whom there is attachment of the tumor with major vessels or in whom the vessels are encased by the tumor, wide limb-saving resection can be achieved by en-bloc resection of the primary tumor and the vessels. In this respect a contamination of the vessels is no longer a contra-indication for a limb-saving procedure. CONCLUSION: The described method is safe, has a relatively low complication rate comparable with rotationplasties and allows a limb-saving procedure.  相似文献   

16.
The present status of hepatic resection for hepatocellular carcinoma (HCC) is reviewed with special reference to the vascular aspects. Hepatic resection combined with portal tumor thrombectomy has been attempted in Japan. This procedure may be effective in the prevention of rupture of esophageal varices and making transcatheter arterial embolization possible. According to the report of Yamaoka and his associates, the 1- and 3-year survival rates of 29 patients treated with this combined procedure were 53% and 12%, respectively. This surgical strategy may thus yield survival benefits. In patients with a tumor near the confluence of the major hepatic vein and inferior vena cava, resection of segments 4b, 7, and 8 combined with hepatic vein reconstruction has been performed, which allows functional preservation of the residual liver. The historical development of hepatic vascular exclusion (HVE) is also reviewed. HVE can be performed safely using a centrifugal active pump, even in patients with cirrhosis. Hepatic resection combined with removal of tumor thrombus in the right atrium has been carried out using extracorporeal circulation. There are reports that at least two patients undergoing this operation survived more than 2 years after surgery. The hepatic warm ischemic time should be less than 60 min. Vascular surgery techniques are being increasingly applied in Japan for the treatment of HCC. Such surgery can be performed safely even in patients with cirrhosis. Improvement of long-term survival in patients undergoing such procedures remains an unresolved problem, however.  相似文献   

17.
PURPOSE: Malignant tumors at the proximal humerus are an operative challenge. Radical removal is a principal of tumor surgery but as much functionality as possible should be retained. These conditions often conflict so a compromise has to be reached. This paper proposes a solution to this dilemma, introducing an operative approach, with a new modular prosthesis, to a secondary Paget's osteosarcoma in the proximal humerus. METHODS AND RESULTS: A recently developed humerus modular prosthesis is described, which has been implanted into a patient with Paget's osteosarcoma. In these, mostly elderly, patients, successful operative therapy should combine radical removal with early mobilization. Paget's osteosarcoma is a recognized complication of the disease, and its prognosis is poor. In our patient, the implanted humerus prosthesis allowed a limb-saving procedure to be combined with radical removal of the tumor and postoperative early mobilization. A 3-month follow-up yielded good results with no recurrence of the disease and the patient had satisfactory movement. She was able to resume normal daily life shortly after the operation. CONCLUSION: Implantation of a modular prosthesis of the humerus may allow radical removal of a malignant tumor in that area while achieving early motion. In the literature, amputation is often advocated, as radical treatment with chemotherapy is not a successful option in this elderly patient group. We think the alternative use of a modular prosthesis of the humerus is possible in selected cases. We have encountered no other case in the literature where a limb-saving procedure attempts to preserve as much functionality as possible in Paget's osteosarcoma.  相似文献   

18.
19.
We performed six immediate free flap reconstructions after tumor ablation in 5 children under the age of 15 years presenting with head and neck malignancy. One patient underwent free flap transfer on two separate occasions because of tumor recurrence. There were no flap losses nor were there any complications related to microvascular surgery. Although a pediatric head and neck malignant tumor is rare, surgical resection is the primary therapeutic role for those that are amenable to complete excision. Pediatric microsurgery provides a safe and reliable procedure for reconstruction of head and neck defects after extirpation of the tumor.  相似文献   

20.
The proportion of patients with localized prostate cancer treated by radical prostatectomy is increasing rapidly in Japan. As for the qualifications of patient candidates for radical surgery, various clinical and pathological findings to predict tumor extent and disease-free outcome must be considered carefully. There has been increased interest in the application of neoadjuvant or adjuvant therapy for locally advanced tumor group in order to improve disease-free survival and overall survival. The new anatomical approach to radical prostatectomy with its nerve sparing option assures preservation of erection. This procedure achieves excellent cancer control for patients with a definite organ-confined tumor preoperatively. Finally, more time is needed to obtain information on the long-term outcome after radical prostatectomy.  相似文献   

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