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PubMed1989

Bronchoscopic use of the neodymium-yttrium-aluminium-garnet laser for lesions of the trachea and bronchus.

The neodymium-yttrium-aluminium-garnet laser has proved to be a useful therapeutic tool for the management of endobronchial lesions. Between October 1, 1986 and October 31, 1987, 31 patients received 41 laser treatments at the Peter MacCallum Cancer Institute mainly for bronchial obstruction, haemoptysis or persistent cough. Good symptomatic relief was obtained in the majority of patients with no operative mortality and a moderate morbidity. When the endobronchial lesion is malignant, concurrent radiotherapy is needed to prevent the early recurrence of the cancer.

Adult↗

PubMed1999

[Yttrium 90 DOTATOC: a new somatostatin analog for cancer therapy of neuroendocrine tumors].

Current concepts for the treatment of somatostatin receptor positive tumours have not been very motivating up to now. A promising alternative could be the new peptidic vector DOTA-D-Phe1-Tyr3-Octreotide (DOTATOC) recently developed in Basel. It may be labelled with the beta-emitter yttrium-90 (90Y) for internal radiotherapy after systemic application. Pilot therapy studies have shown convincing results with this new radiopharmaceutical. These studies are presented with regard to efficacy and possible toxicity. In summary, the new receptor-mediated 90Y-DOTATOC therapy led to tumour response in the majority of patients, and only in some receiving high cumulative doses of > 200 mCi per m2 body surface renal and hematological toxicity due to irradiation occurred. For the reduction of renal accretion, concepts with concomitant amino acid infusions containing L-lysine in a higher concentration are currently under way.

Female↗

PubMed1999

Yttrium-90 DOTATOC: first clinical results.

In a pilot study, DOTA-d-Phe(1)-Tyr(3)-octreotide (DOTATOC), which can be labelled with the beta-emitting radioisotope yttrium-90, has recently been used for the treatment of patients with advanced somatostatin receptor-positive tumours who had no other treatment option. The aim of the present study was to elucidate the therapeutic potential of (90)Y-DOTATOC in a larger number of patients employing a standardized treatment protocol. Careful attention was paid to any side-effects (renal and/or haematological toxicity). Of 44 patients with advanced somatostatin receptor-positive tumours of different histology, 29 could be included in the study. The 15 patients who were excluded from the study protocol were assigned to our institution for purely compassionate reasons. The 29 patients who were included received four or more single doses of (90)Y-DOTATOC with ascending activity at intervals of approximately 6 weeks (cumulative dose 6120+/-1347 MBq/m(2)) with the aim of performing an intra-patient dose escalation study. In total, 127 single treatments were given. In eight of these 127 single treatments, total doses of > or = 3700 MBq were administered. In an effort to prevent renal toxicity, two patients received Hartmann-Hepa 8% solution during all therapy cycles, while 13 patients did so during some but not all therapy cycles; in 14 patients no solution was administered during the therapy cycles. The treatment was monitored by computed tomography and indium-111 DOTATOC scintigraphy. Blood parameters were controlled weekly, while tumour markers and liver enzymes were controlled 6-weekly. Of the 29 patients, 24 patients showed no severe renal or haematological toxicity (toxicity < or = grade 2 according to the National Cancer Institute grading criteria). These 24 patients received a cumulative dose of < or = 7400 MBq/m(2). Five patients developed renal and/or haematological toxicity. All of these five patients received a cumulative dose of >7400 MBq/m(2) and had received no Hartmann-Hepa 8% solution during the therapy cycles. Four of the five patients developed renal toxicity; two of these patients showed stable renal insufficiency and two require haemodialysis. Two of the five patients exhibited anaemia (both grade 3) and thrombopenia (grade 2 and 4, respectively). To date, 20 of the 29 patients have shown a disease stabilization, two a partial remission, four a reduction of tumour mass <50% and three a progression of tumour growth. (90)Y-DOTATOC could be a powerful and promising new therapeutic agent for anti-cancer treatment - at least in terms of an adjuvant starting point of the disease. However, problems with toxicity have to be solved. Evaluation of the effect of amino acid infusions (e.g. Hartmann-Hepa 8% solution) during (90)Y-DOTATOC treatments with the aim of reducing renal toxicity is ongoing.

Adult↗

PubMed2000

Phase II trial of yttrium-90-DOTA-biotin pretargeted by NR-LU-10 antibody/streptavidin in patients with metastatic colon cancer.

A Phase II study of yttrium-90-tetra-azacyclododecanetetra-acetic acid-biotin (90Y-DOTA-biotin) pretargeted by NR-LU-10 antibody/streptavidin (SA) was performed. The primary objectives of the study were to evaluate the efficacy and safety of this therapy in patients with metastatic colon cancer. Twenty-five patients were treated with a single dose of 110 mCi/m2 (mean administered dose, 106.5 +/- 10.3 mCi/m2) of 90Y-DOTA-biotin. There were three components of the therapy. Patients first received NR-LU-10/SA on day 1. A clearing agent (biotin-galactose-human serum albumin) was administered approximately 48 h after the NR-LU-10/SA to remove residual circulating unbound NR-LU-10/SA. Lastly, 24 h after administration of clearing agent, patients received biotin-DOTA-labeled with 110 mCi/m2 90Y. All three components of the therapy were administered i.v. Both hematological and nonhematological toxicities were observed. Diarrhea was the most frequent grade 4 nonhematological toxicity (16%; with 16% grade 3 diarrhea). Hematological toxicity was less severe with 8% grade 3 and 8% grade 4 neutropenia and 8% grade 3 and 16% grade 4 thrombocytopenia. The overall response rate was 8%. Two partial responders had freedom from progression of 16 weeks. Four patients (16%) had stable disease with freedom from progression of 10-20 weeks. Despite the relatively disappointing results of this study in terms of therapeutic efficacy and toxicity, proof of principle was obtained for the pretargeting approach. In addition, valuable new information was obtained about normal tissue tolerance to low-dose-rate irradiation that will help to provide useful guidelines for future study designs.

Adult↗

PubMedDate not supplied

Yttrium-90 delivered via a centering catheter and afterloader, given both before and after stent implantation, inhibits neointima formation in porcine coronary arteries.

BACKGROUND: Intracoronary radiation (IR) studies have shown reduction of neointima formation (NF). Extrapolation of animal studies with beta-radiation to clinical trials have shown variable results, which may be related to dosimetry, centering issues, and/or shielding of beta-rays by the stent metal. We examined the effect of yttrium-90 (90Y), a pure beta-emitter delivered via an automatic afterloader to a centering catheter, on the inhibition of NF in balloon-injured (BI) porcine coronary arteries as well as in arteries receiving 90Y either prior to or following stent implantation (SI). METHODS: Twenty-three swine (44 coronary arteries) were studied. In the first study, IR (18 Gy at 1.2 mm from the balloon surface) was administered in 17 arteries following BI, while eight control arteries were subjected to BI only. In the second study, 10 swine (19 coronary arteries) underwent SI. IR (18 Gy) was administered in six arteries before and in eight arteries after SI, while five control arteries received SI only. The animals were sacrificed 2 weeks after BI and 4 weeks after SI. Their coronaries were perfusion fixed and stained, and vessel parameters (intimal area [IA] and medial fracture length [FL]) were analyzed by computer-aided histomorphometry. RESULTS: Arteries subjected to IR following BI had less NF compared to controls (IA/FL = 0.14 +/- 0.2 mm vs. 0.49 +/- 0.2 mm; P = 0.003). IA was reduced significantly in the arteries receiving radiation before and after SI compared to controls (0.92 +/- 0.98 and 0.00 +/- 0/00 vs. 2.72 +/- 1.2 mm2; P = 0.014), despite similar SI in all groups. CONCLUSIONS: IR with 90Y delivered via a centering catheter is safe and effective with complete and homogenous inhibition of NF in the context of BI or SI in the porcine coronary model.

Animals↗

PubMed1999

Hepatic radioembolization with Yttrium-90 glass microspheres for treatment of primary liver cancer.

OBJECTIVE: To study the clinical results of hepatic radioembolization with Yttrium-90 (90Y) glass microspheres in the treatment of primary liver cancer. METHODS: Seventeen patients with liver cancer were treated with glass microspheres from August 1996 to May 1998. Hepatic radioembolization with 90Y and lipiodol-ultrafluid was used. Percutaneous port-catheter system (PCS) implantations via femoral artery were performed in 12 patients. RESULTS: In the 17 patients, their mean ratio of absorbed doses between tumor and normal liver was 2.4:1. CT showed a significant reduction in tumor size in 11 of the 17 patients. Average survival was 19.5 months. The indwelling catheters of all the 12 patients were patent and no catheter tip locations were found. CONCLUSIONS: 90Y glass microsphere is one of the best radioisotopes. Not only good responses to the therapy of 90Y glass microspheres can be achieved in patients with metastatic liver cancer, but also in those with primary liver cancer, specially the localized or hypervascular mass. The patients with massive arterioportal shunt should not be limited to this form of radiation therapy. The percutaneous PCS implantation via the femoral artery is a new passageway for the treatment of primary liver cancer with 90Y glass microspheres and other interventional therapy.

Adult↗

PubMed1975

Radiation synovectomy of the rheumatoid knee with yttrium 90.

The use of radioactive yttrium (90Y) in the treatment of rheumatoid knee joints is described. Clinical results in 48 knees after a mean observation period of more than 3 years are reported: 60 percent excellent or good at one year, 46 percent at two years, 33 percent at three years and 17 percent at four years. The number of failures or relapses exceeded 50 percent between 30 and 36 months. The average rate of relapse in successful cases was 12.8 percent per year. The most important factors associated with unsatisfactory result were advanced articular destruction and progression of the systemic disease.

Adolescent↗

PubMedDate not supplied

Three-dimensional computerized stress analysis of commercially pure titanium and yttrium-partially stabilized zirconia implants.

PURPOSE: The purpose of this study was to use three-dimensional finite element analysis to analyze stress distribution patterns in Re-Implant implants made of commercially pure titanium (cpTi) and yttrium-partially stabilized zirconia (YPSZ). MATERIALS AND METHODS: Two three-dimensional finite element analysis models of a maxillary incisor with Re-Implant implants were made, surrounded by cortical and cancellous bone. A porcelain-fused-to-metal crown for the cpTi implant and a ceramic crown for the YPSZ implant were modeled. Stress levels were calculated according to the von Mises criteria. RESULTS: Higher stresses were observed at the area where the implant entered the bone. Stresses were higher at the facial and lingual surfaces than the proximal ones. In cortical bone and at the junction of cortical and cancellous bone, stress distribution presented a pattern of alternating higher (4.0 to 5.0 MPa) and lower (1.3 to 2.0 MPa) stress areas. Higher stresses were found at the apical third of the implant-to-bone junction as well. CONCLUSION: Re-Implant implants presented a pattern of low, well-distributed stresses along the entire implant-to-bone interface. YPSZ implants had very similar stress distribution to cpTi implants and may be viable esthetic alternatives, especially in maxillary anterior regions.

Ceramics↗

PubMedDate not supplied

Root instrumentation with an erbium:yttrium-aluminum-garnet laser: effect on the morphology of fibroblasts.

OBJECTIVE: The purpose of this study was to evaluate the effect of erbium:yttrium-aluminum-garnet laser instrumentation of root surfaces on the morphology of fibroblasts from continuous lineage. METHOD AND MATERIALS: Dentinal slices with 4 mm2 of surface area were obtained from teeth extracted for severe periodontal involvement. Specimens were assigned to one of three treatment groups: group 1, application of the laser with an energy level of 250 mJ at 103 pulses per second; group 2, application of the laser with an energy level of 80 mJ at 166 pulses per second; and group 3, similar to group 2, but with concomitant water irrigation of the device. The specimens were incubated in multiwell plates containing cell culture media. After 24 hours, the specimens were submitted to routine preparation for scanning electron microscopy. Three independent and blind examiners used photomicrographs to evaluate the morphology of the fibroblasts: 0 = without cells; 1 = flat cells; 2 = round cells; and 3 = combination of round and flat cells. RESULTS: Statistical analysis indicated that there were significant differences among treatment groups and that group 3 was significantly different from groups 1 and 2. CONCLUSION: There was no difference between groups 1 and 2 in the morphology of fibroblasts. Laser instrumentation with concomitant irrigation impaired the adhesion of fibroblasts to dentinal surfaces.

Aluminum Silicates↗

PubMed2005

[Yttrium- Aluminium Garnet Crystal (I)].

The Yttrium- Aluminum Garnet Crystal is synthetically obtained and represents the active medium of the Nd: YAG, Ho: YAG, Er: YAG lasers. These solid state lasers showed very good results in Ophthalmology, due to their emission in different regimes (continuous wave or giant short pulses), at different wavelengths (near IR and starting from it in UV or visible spectre), the ability to focus the radiation through simple optic systems or the transmission to narrow, hard accessible spaces using flexible optic fibers. The high efficiency of these lasers reported in ophthalmology is obtained by the photo-disruptive or thermic mechanism of the laser beams. This paper introduces the properties of the laser radiation, the structure and the way the YAG laser works and the applications of these lasers in Ophthalmology (such as posterior capsulotomy, iridotomy or trabeculoplasty) as well.

Aluminum Silicates↗

PubMedDate not supplied

Hepatic intra-arterial injection of Yttrium-loaded microspheres for liver metastasis secondary to colorectal cancer: best soups are sometimes made from old recipies.

Colorectal cancer is a severe disease with a significant incidence in Western world. In the course of disease, about 40% of patients will eventually develop metastases to the liver. The majority of them will never be candidate for curative surgical management. For those patients, systemic or intra-hepatic chemotherapy is the treatment's cornerstone. Unfortunately, despite evident improvements and apparition of several active new agents, no hope of cure emerges on the agenda for now. Hepatic intra-arterial injections of radioactive devices have since a long time drawn interest from the medical community. An anti-tumoural activity has been demonstrated with Yttrium-loaded microspheres injected in the hepatic artery for several liver neoplasms including metastases from colorectal cancer. We lack however the results of large randomized phase III trials to define clearly the place of those interventional therapies in the management of colorectal cancer metastatic to the liver.

Clinical Trials, Phase II as Topic↗

PubMed2006

[Labeling of CDTPA-dianhydride-coupled CD45 monoclonal antibody with yttrium-90].

OBJECTIVE: To explore the methods for labeling CDTPA-coupled CD45 monoclonal antibody (mAb) with yttrium-90 ((90)Y) for potential acute myeloid therapy. METHODS: CD45 mAb was labeled with (90)Y by CDTPA and the labeling rate, radiochemical purity, final specific activity, and immunological activity of the mAb were detected. RESULTS: With the optimal molar ratio of CDTPA/Ab at 20:1, the labeling rate was 95%, radiochemical purity 99.8%, and final specific activity 1.9 mCi/mg. This conjugate was stable in vitro with comparable immunological activity in comparison with unlabeled CD45 mAb. CONCLUSION: (90)Y-CDTPA-CD45 mAb possesses good properties as an ideal targetting therapeutic agent for acute leukemia.

Anhydrides↗

PubMed2006

[Determination of trace lead and iron in nickel chloride and manganese sulfate by flame atomic absorption spectrometry after coprecipitation with yttrium phosphate].

Using yttrium phosphate as the coprecipitation collector for the separation and preconcentration of trace lead and iron in nickel chloride and manganese sulfate, flame atomic absorption spectrometric (FAAS) determination was described in the present paper. Coprecipitation parameters including the pH of the solution, and the amounts of YCl3 and H3 PO4 were discussed. It was found that lead and iron in nickel chloride could be coprecipitated quantitatively in the range of pH 3.0-4.0, and so could be lead in manganese sulfate. The detection limits (3sigma) of lead and iron in 20 mL solution were 1.63 x 10(-2) mg x L(-1) and 4.58 x 10(-2) mg x L(-1) respectively. In NiCl2 solution the standard addition recoveries for lead and iron were 100.91% and 99.73% respectively, and in MnSO4 solution the standard addition recoveries were 99.45% and 98.98% respectively. The method has eliminated the interference of matrix, and the result is satisfied.

Chemical Precipitation↗

PubMed1991

Radiotherapy in mice with yttrium-90-labeled anti-Ly1 monoclonal antibody: therapy of the T cell lymphoma EL4.

Yttrium-90 is a potent beta-emitting radionuclide with potential for therapy of lymphoma. A monoclonal antibody against Ly1, the murine homologue of human CD5, was labeled with 90Y and found to selectively bind to Ly1-positive, radiation-sensitive, EL4 mouse lymphoma cells. When tested in this aggressive model of T cell lymphoma, in vivo studies in C57BL/6 mice showed that a single 140-microCi i.p. dose of 90Y-anti-Ly1, given 1 day after i.v. injection of a lethal dose of EL4 cells, resulted in significant but transient improvement in survival. Protection was selective, since a 90Y-labeled irrelevant control antibody did not prolong survival. Biodistribution studies showed that protection was likely limited by inadequate localization of labeled antibody to tumor. Importantly, labeled anti-Ly1 specifically localized in the immunological tissue (spleen and thymus) and lowered the WBC count, perhaps limiting the tolerated dose. Myelosuppression, which is considered one of the major side effects associated with 90Y usage, was not a lethal complication, since WBC counts recovered in mice given a 140-microCi dose of 90Y-anti-Ly1 without EL4 cells and 100% of these animals survived. The maximum tolerated dose was less than 200 microCi. Despite the high localization of 90Y-anti-Ly1 in spleen, splenectomies of tumor-injected mice did not improve the antitumor efficacy of radiolabeled antibody. Further evidence for inadequate delivery of radionuclide to tumor was shown when external total-body irradiation was given to mice given injections of a lethal dose of EL4 tumor cells. Comparison of internal and external irradiation studies indicated that the partially protective effect of 140 microCi 90Y-Ly1 was equivalent to external radiation of only 100-200 cGy. Because this model reflects the current clinical limitations of radiolabeled antibodies for therapy, including partial antitumor efficacy, delivery of labeled anti-T cell antibodies to the immune system, and low maximum tolerated dose, the model may be useful for examining strategies which could increase the tolerated dose and therapeutic efficacy.

Animals↗

PubMed1990

[The treatment of gonarthritis with yttrium-90].

200 patients with gonarthritis--142 patients with rheumatoid arthritis, 38 patients with psoriatic arthritis, 7 patients with ankylosing spondylarthritis, 2 patients with collagenosis, 2 patients with antero-arthritis, 2 patients with hemophilia and 7 patients with gonarthrosis were treated with yttrium-90--4-5 mCi intra-articularly. All patients were with high activity of the process and were in the I up to the III roentgenologic stage. The results in 81.25% of the 80 patients with rheumatoid arthritis I and II stage and in 62.57% of the 62 patients in the III stage were considered "very good" and "good". Since the results in these groups are very close and the differences are insignificant it could assumed that synoviorthesis is a useful method also in the III stage of rheumatoid arthritis. The results in the other types of arthritis were favourable in 79.8% of the patients treated, i. e. they are similar to those in rheumatoid arthritis. This allows the assumption that synoviorthesis is a universal method for local treatment of all types of arthritis. The follow up of the patients for one year established a reliable reduction of the articular edema and improvement of the joint movements.

Adult↗

PubMed1990

Changes in aqueous outflow after in vitro neodymium: yttrium aluminum garnet laser cyclophotocoagulation.

To examine the possible role of transscleral outflow routes, enucleated human and porcine eyes underwent noncontact neodymium:yttrium aluminum garnet (Nd:YAG) laser cyclophotocoagulation 3 mm posterior to the limbus. Pars plana lesions were verified histologically. The eyes were perfused with saline solution at 50 mm Hg perfusion pressure, placing the tip of the needle into the hyaloid orbicular space. The outflow facility was 0.072 microliter/min/mm Hg in paired controls and 0.105 microliter/min/mm Hg in human lasered eyes, a difference of 31%. In porcine eyes the difference was 43%. Since concepts of aqueous production, impaired circulation, and inflammation do not apply to enucleated eyes, the increase may be related to pars plana transscleral flow facilitated by disruption of the neuroepithelial barrier.

Animals↗

PubMed1990

The contact neodymium-yttrium aluminum garnet laser. A new approach to arthroscopic laser surgery.

Arthroscopic treatment of meniscal lesions has been modified as technological advances have occurred. However, alternatives to conventional arthroscopic cutting tools, including electrocautery and CO2 lasers, have thus far met with limited success. The recent development of a sapphire tip has enabled the use of the neodymium-yttrium aluminum garnet (Nd-YAG) laser in a contact mode in a saline medium. This study compares the biology of the Nd-YAG laser to that of electrocautery and scalpel techniques with respect to its effects on articular cartilage and the meniscus. The contact Nd-YAG laser has advantages over both scalpel and electrocautery with regard to its effects on articular cartilage. It also has significant biologic advantages over electrocautery for meniscal lesions. Although in its infancy in the clinical setting, the contact Nd-YAG laser represents the possible beginning of a new era for application of laser energy in arthroscopy.

Aluminum↗

PubMed1990

Yttrium-90-labeled monoclonal antibody for therapy: labeling by a new macrocyclic bifunctional chelating agent.

Yttrium-90 (90Y) is a promising radiometal for therapy of cancer due to its high-energy beta emission and a physical half-life of 2.67 days. Bifunctional chelating agents based on DTPA cyclic anhydride or EDTA do not form Y(III) complexes that are stable under physiologic conditions. A new macrocyclic bifunctional chelating agent based on 1,4,7,10-tetraazacylododecane-N,N',N",N"'-tetraacetic acid (DOTA) forms a stable Y(III) complex. It was converted to p-bromoacetamidobenzyl-DOTA (BAD), and conjugated to monoclonal antibody Lym-1 via 2-iminothiolane, either as the free ligand or as the 88Y chelate. Stability studies of Lym-1-2IT-BAD-88Y in human serum in vitro showed no measurable loss of Y(III) from the ligand over a 25-day period. In Raji-tumored mice, tumor uptake was 16.8% of the injected dose per gram of tissue on Day 3. The bone uptake was 2.0, 3.6, and 2.1% injected dose per gram of tissue on Day 1, 3, and 5, respectively. The biodistribution of the control 88Y-citrate demonstrated continuous increase in bone uptake from 13.8% injected dose per gram on Day 1 to 24.9% injected dose per gram on Day 4.

Animals↗