Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A 38-year-old male was admitted with edema of the neck and face. Chest X-ray revealed a mediastinal tumor. On chest CT and MRI, a tumor infiltrating the superior vena cava and bilateral brachiocephalic veins in the upper mediastinum was observed. Venography revealed obstruction of bilateral brachiocephalic veins. The tumor was diagnosed as thymoma by percutaneous biopsy, but since it was of stage III according to Masaoka's classification, complete extirpation was considered to be impossible. Preoperative chemotherapy with multiple drugs (CDDP, ADM, VCR, CPA) was administered. The superior vena cava syndrome resolved and the tumor diminished in size. Because of leukopenia, rhG-CSF was also used. The tumor infiltrated the left brachiocephalic vein; therefore, total resection and left brachiocephalic vein reconstruction were performed. Histopathological examination showed extensive, necrosis and fibrosis containing residual thymoma. Postoperatively, similar chemotherapy and cobalt irradiation (40 Gy) to the superior mediastinum were performed. We thus present a case of invasive thymoma which responded to preoperative chemotherapy.
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PMID:[A case of invasive thymoma responsive to preoperative chemotherapy]. 150 97

This is a retrospective analysis of 143 patients with histologically confirmed epidermoid carcinoma of the nasopharynx treated with definitive irradiation. Patients were treated with a combination of Cobalt-60, 4 to 6 MV X rays, and 18 to 25 MV X rays to the primary tumor and the upper necks, excluding the spinal cord at 4000 to 4500 cGy to total doses of 6000 to 7000 cGy. At 10 years the actuarial primary tumor failure rate was 15% in T1, 25% in T2, 33% in T3, and 60% in T4 lesions. The corresponding failure rate in the neck was 18% for N0, 14% for N1, and 33% for N2 and N3 lymphadenopathy. The incidence of distant metastasis was related to the stage of the cervical lymphadenopathy: 16% in patients with N0-N1 nodes compared with 40% in the N2-3 node group. The actuarial 10-year disease-free survival rate was 55% to 60% for T1-3N0-1 tumors, 45% for T1-3N2-3 tumors, 35% for T4N0-1, and 20% for T4N2-3 lesions. The overall 10-year survival rate was about 40% for patients with T1-2N0-1 tumors, 30% for those with T3 any N stage tumors, and only 10% for the patients with T4 lesions. Multivariate analysis showed that tumor stage and histological type, cranial nerve involvement, patient age, and doses of irradiation to the nasopharynx were significant prognostic factors for local/regional tumor control. Increasing doses of irradiation resulted in nasopharynx tumor control in 80% of the patients receiving 6600 to 7000 cGy and 100% of those receiving over 7000 cGy in the T1, T2, and T3 tumors. However, the tumor control rate did not rise above 55% even for doses over 7000 cGy in the T4 lesions. Local tumor control was higher in patients who had simulation (55/78 = 71%) compared with those on whom simulation was not performed (34/61 = 56%) (p = 0.10). Moreover, patients with more than 75% of the reviewed films judged as adequate had 69% primary tumor control (66/96) compared with 53% (23/43) for those with fewer than 75% adequate portal films (p = 0.07).
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PMID:Carcinoma of the nasopharynx: factors affecting prognosis. 158 46

Since 1979, 157 patients with T2, T3, or T4 cancer of the lower rectum have been treated by a short course of irradiation, 30 Gy within 12 days by cobalt 60 using 120 degrees arc rotation on a sacral field, followed by a 2-month rest before surgery. The operative specimens were tumor-free in 13% of patients, Dukes' A in 40% of patients, Dukes' B in 22% of patients, and Dukes' C in 25% of patients. Three (1.9%) patients died postoperatively. At 3 years (107 patients) and 5 years (74 patients) the rates of death of local failure were 7.5% and 9.5%, respectively. The 3-year and 5-year disease-free survival were 71% and 58%. Since 1983, the surgeons took advantage of the tumor regression to carry out sphincter-saving operation in 67 patients with T2, T3, and T4 tumors of the lower third of the rectum. The proportion of patients treated by restorative surgery instead of abdominoperineal resection has grown significantly during the past 4 years, from 22% to 71%. Diverting colostomy was performed in 10 patients. Anastomotic leakages were observed in 7 patients. Of 31 patients who underwent low anterior resection and were followed 3 to 7 years (mean 4.5 years), 5 patients died of distant metastasis and 3 patients are alive after segmental hepatectomy. One patient had local recurrence which was controlled by abdominoperineal resection. The rate of 3-year disease-free survival was 77%.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Role of pre-operative irradiation for anal preservation in cancer of the low rectum. 158 88

"Radiosurgery" is the term for a special concept in radiotherapy. It describes a percutaneous, stereotactically guided irradiation delivering a single high dose with collimated narrow beams. The precise stereotactic localization of the target point and a steep dose gradient outside the target volume allow the administration of high doses to a lesion without damage to adjacent normal tissue. Risk of necrosis, due to a dose volume relationship represents the limits of radiosurgery. Units for radiosurgery were designed at Stockholm using multiple external cobalt-60-gamma sources, at Boston operating with protons of a cyclotron, at Berkeley operating with helium ions accelerated by a synchrocyclotron. An attractive alternative to these complicated and expensive facilities is the use of a modified linear accelerator. At the German Cancer Research Center in Heidelberg such a system was developed and has been available for the treatment of patients since 1984. Though, data of over 100,000 patients with vascular malformations and cancer disease are available worldwide, the indication for this therapy is validated only for a minority of entities. In cases of inoperable arteriovenous malformations favourable results in achieving obliteration range between 60% and 100% were obtained. Median survival for solitary brain metastases with controlled, extracerebral tumor diseases were between nine and twelve months. Up to now, advantages of stereotactic irradiation for benign tumor masses could not be proven. Therefore, randomized trials should be initiated in this field, considering decisive improvements in local tumor control with techniques of microsurgery and fractionated, postoperative radiotherapy during the last few years.
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PMID:[Stereotactic convergent-beam irradiation: its current prospects based on clinical results]. 159 59

Thirty-six patients with advanced hematologic malignancy were entered into a Phase I study designed to define the maximum tolerated dose of unshielded total body irradiation delivered from dual 60 Cobalt sources at an exposure rate of 8 cGy/min and given in fractions twice daily for total doses ranging from 12 Gy to 17 Gy. All patients received cyclophosphamide, 120 mg/kg administered over 2 days before total body irradiation. Allogeneic marrow was infused from HLA-identical siblings (n = 29) or one locus HLA incompatible family members (n = 3); three patients received cryopreserved autologous marrow and one patient received syngeneic marrow. The maximum tolerated dose of total body irradiation given as 2 Gy fractions twice a day was 16 Gy. One of eight patients receiving 12 Gy, none of four receiving 14 Gy, three of 20 receiving 16 Gy, and two of four receiving 17 Gy developed severe (Grade 3-4) regimen-related toxicity. The primary dose limiting toxicity was pneumonitis, followed by veno-occlusive disease of the liver, renal impairment, and mucositis. Five patients (14%) are alive, four disease-free 798-1522 days posttransplant. Twenty (56%) relapsed posttransplant. Further investigation of regimens containing 16 Gy of hyperfractionated total body irradiation is warranted to assess anti-tumor efficacy.
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PMID:Marrow transplantation following escalating doses of fractionated total body irradiation and cyclophosphamide--a phase I trial. 163 36

Using proton beam therapy, high doses have been delivered to chordomas and chondrosarcomas of the base of skull and cervical spine. Dose inhomogeneity to the tumors has been accepted in order to maintain normal tissue tolerances, and detailed attention to patient immobilization and to precise positioning has minimized the margins necessary to ensure these dose constraints. This study examined the contribution of precise positioning to the better dose localization achieved in these treatments. Three patients whose tumors represented different anatomic geometries were studied. Treatment plans were developed which treated as much of the tumor as possible to 74 Cobalt-Gray-Equivalent (CGE) while maintaining the central brain stem and central spinal cord at less than or equal to 48 CGE, the surface of the brain stem, surface of the spinal cord, and optic structures at less than or equal to 60 CGE, and the temporal lobes at less than or equal to 5% likelihood of complication using a biophysical model of normal tissue complication probability. Two positioning accuracies were assumed: 3 mm and 10 mm. Both proton beam plans and 10 MV X ray beam plans were developed with these assumptions and dose constraints. In all cases with the same positioning uncertainties, the proton beam plans delivered more dose to a larger percentage of the tumor volume and the estimated tumor control probability was higher than with the X ray plans. However, without precise positioning both the proton plans and the X ray plans deteriorated, with a 12% to 25% decrease in estimated tumor control probability. In all but one case, the difference between protons with good positioning and poor positioning was greater than the difference between protons and X rays, both with good positioning. Hence in treating these tumors, which are in close proximity to critical normal tissues, attention to immobilization and precise positioning is essential. With good positioning, proton beam therapy permits higher doses to significantly more of the tumor in these sites than do X rays.
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PMID:Importance of precise positioning for proton beam therapy in the base of skull and cervical spine. 165 8

A comparison of the intracellular DNA strand scission activities of the antitumor drug bleomycin, three of its metal complexes, demethyl bleomycin A2, and iron-containing, redox-inactivated bleomycin in Ehrlich ascites tumor cells was performed by means of the alkaline elution technique. This comparison was aided by use of CoCl2 to eliminate or minimize post-cell lysis strand scission by bleomycin in aliquots of treated cultures. No strand scission resulted from treatment of cells with the cobalt complex. The levels of intracellular DNA degradation by copper bleomycin and iron bleomycin were equivalent to those produced by metal-free bleomycin. The findings are correlated with previous measurements of growth inhibition by these three bleomycins as well as by cobalt bleomycin and related to the concentrations of radiolabeled bleomycin bound to DNA after treatment of cells with each form of drug. In comparison, both demethyl bleomycin A2 and iron-containing, redox-inactivated bleomycin showed marked, concentration-dependent reductions in random DNA strand scission, as compared with unmodified bleomycin or iron bleomycin prepared from Fe(III) and bleomycin. However, the fraction of DNA from cells treated with these two bleomycins, which eluted through filters prior to alkaline denaturation, was equivalent to that for unmodified bleomycin and Fe(III)bleomycin. The generation of this class of damaged DNA correlates more closely with concentration-dependent growth inhibition by each of the six forms of bleomycin than the degree of random strand scission.
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PMID:Intracellular DNA strand scission and growth inhibition of Ehrlich ascites tumor cells by bleomycins. 169 48

Tumor concentrations of the chemotherapeutic drug, bleomycin, labeled with cobalt-57 (Co-bleo) were compared in mouse tumor models and in human lung tumors using quantitative single-photon emission computed tomography. Drug concentrations in histologically similar human tumors showed marked variability for the same injected dose (ID). Small cell carcinomas showed concentrations between 1.09 and 8.85 %ID/cc x 10(-3) while non-small cell lung tumors showed a concentration variation between 0.36 and 6.75 %ID/cc x 10(-3). In contrast to the situation in human tumors, uptake in mouse tumors showed only slight variability in animals with the same tumor model. EMT-6 tumors in mice showed at 6 hr significantly higher uptake of Co-bleo (p less than 0.001) and significantly higher tumor-to-lung ratio (p less than 0.001) when compared to murine fibrosarcomas. The EMT-6 tumors in contrast to the fibrosarcomas responded to bleomycin treatment in a dose dependent manner. The results indicate that while in mice the tumor dose closely follows the administered dose, in humans, the tumor dose and the tumor-to-lung ratio in the individual patient cannot be predicted from the administered dose.
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PMID:Administered dose and tumor dose of bleomycin labeled with cobalt-57 in mice and men. 170 87

Concentrations of bleomycin labeled with cobalt 57 (Co-bleo) over time were measured in vivo in 17 patients with 32 sites of lymphoma and 18 patients with lung tumors after administration of the same dose of bleomycin. There were marked variations in individual tumor drug concentrations even among tumors with the same histologic type, indicating that the tumor concentration of this drug in individuals cannot be predicted from the administered dose. Also, tumor concentration could not be predicted from the area under the concentration over time curve (AUC) of Co-bleo in the blood; there was no correlation (r = 0.53) between the AUC and the concentration in the tumor at any point in time between 30 minutes and 8 hours after injection. There was no significant difference in the percent of the injected dose per milliliter (%ID/ml) which was delivered to the tumor when low and high amounts of bleomycin were administered to the same patient. Also, a good correlation (r = 0.88) between the %ID/ml over time was found when injection of low and high doses of bleomycin were compared. The results indicate that using quantitative single photon emission computed tomography (SPECT) and a labeled tracer dose it is possible to predict what fraction of the dose of a chemotherapeutic drug will concentrate in an individual patient's tumor in vivo. They also show that, for bleomycin, escalation of dose will result in a proportional increase of tumor concentration. This increase depends on individual properties of tumors which can be measured quantitatively in vivo by SPECT and are expressed as percent of %ID/ml of tumor tissue.
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PMID:In vivo measurements of the fraction of dose of bleomycin labeled with cobalt 57 delivered to human tumors. 170 47

Experience with the use of external beam conventional radiation over a period of several decades has shown that in every instance where there has been a major advance in the physical delivery of radiation to the tumor (beam energy and characteristics and precise tumor dose delivery) there has been a corresponding major improvement in the treatment results. The advent of megavoltage sources following the invention and use of Cobalt 60 and medical linear accelerator units during the late 1940's and early 1950's and their major impact on tumor control and patient survival in solid tumors such as carcinoma of the prostate, Hodgkin's Disease, head and neck tumors and cancer of the cervix are being discussed. Most recently, the use of computerized tomography and computer systems for treatment planning is likely to show a further improvement in the therapeutic results.
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PMID:Does improved depth dose characteristics and treatment planning correlate with a gain in therapeutic results? Evidence from past clinical experience using conventional radiation sources. 174 Mar 90


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