99mTc-HYNIC octreotide in neuroblastoma
Nuclear Medicine Center, Clinical Hospital, University of Uruguay, Av. Italia s/n, C.P. 11600, Montevideo, Uruguay. Annals of Nuclear Medicine
(Impact Factor: 1.68).
12/2008; 22(9):817-9. DOI: 10.1007/s12149-008-0201-9
Disease status assessment of neuroblastoma patients requires computed tomography (or magnetic resonance imaging), bone scan, metaiodobenzylguanidine (MIBG) scan, bone marrow tests, and urine catecholamine measurements. There is no clinical experience concerning the evaluation of these patients by means of technetium-99m (99mTc)-somatostatin analog scintigraphy. Furthermore, these radiopharmaceuticals are promising imaging agents owing to their lower cost, availability, dosimetry, and ease of preparation. An 8-year-old boy already diagnosed with stage-IV neuroblastoma received chemotherapy. In the follow-up, after obtaining the parents' informed consent, iodin 131 (131I)-MIBG and 99mTc-6-hydrazinopyridine-3-carboxylic acid (HYNIC)-octreotide scans were done on separate days to evaluate tumor extension. Even as the 131I-IBG scan showed mild diffuse uptake in the projection of both lung hili, the 99mTc-HYNIC-octreotide scan showed multiple axial and appendicular bone uptakes and paravertebral, abdominal, mediastinal, and supraclavicular ganglionar uptakes. The 99mTc-HYNIC-octreotide showed much more lesion extension than the 131I-MIBG. Therefore, 99mTc-HYNIC-octreotide may be a promising radiopharmaceutical for the evaluation of neuroblastoma patients. This finding justifies the preliminary evaluation of this tracer in the context of a clinical trial.
Available from: Gabor Mezo
[Show abstract] [Hide abstract]
ABSTRACT: Tumor targeting with peptides is based on the discovery that receptors for many regulatory peptides are overexpressed in tumor cells, compared with their expression in normal tissues. Consequently, these peptides and their analogues can be used as carriers/targeting moieties for the preparation of diagnostic and therapeutic agents that have increased selectivity and decreased peripheral toxicity.
Here an overview is given of the most relevant gonadotropin-releasing hormone (GnRH) and somatostatin derivatives, as well as of their applications in cancer diagnosis and therapy. For this purpose, recently published data in these areas (mostly articles published from 2000 to 2009) were reviewed.
In contrast to other regulatory peptides that stimulate the tumor growth, GnRH and somatostatin derivatives have inhibitory effect; therefore, they were used primarily for the preparation of various conjugates to be used in targeted chemotherapy, targeted radiotherapy, photodynamic therapy, boron neutron capture therapy and cancer diagnosis. Some of these conjugates have already found clinical applications, whereas others are now in preclinical and clinical trials.
Tumor targeting with hormone peptides provides a basis for the development of new diagnostic and therapeutic approaches for cancer.
Available from: mednat.org
[Show abstract] [Hide abstract]
ABSTRACT: the aim of the Di Bella Method (DBM) is to try to overcome the high toxicity level and the limited efficacy of the current medical treatments for cancer.
using Melatonin, Retinoids, and vitamins E, D3, and C, components of the extracellular matrix, the DBM reinforces those means that Physiology considers essential for life. Acting together, these differentiating molecules also have an antiangiogenic and antiproliferative effect. Cabergoline and/or Bromocriptin negatively regulate Prolactin, the ubiquitary mitogenic hormone. This effect is reinforced by Somatostatin and/or its analogues by negatively regulating highly mitogenic molecules such as GH and GH-dependent growth factors.
the preliminary results are reported of a retrospective observational study on 553 patients treated with the DBM. These data show that the DBM achieved an evident improvement in the quality of life and a considerable increase in the mean survival rates for every disease and stage with respect to the data available in the literature relative to chemotherapy and/or monoclonal antibodies. The result was achieved without any of the known significant toxic effects of chemotherapy and (albeit to a lesser extent with respect to chemotherapy) of monoclonal antibodies. The invalidating causes which removed all scientific credibility from the DBM experiments carried out in Italy in 1998 are also reported.
I considered it of use to inform the scientific community of the rationale, the mechanism of action, the scientific basis and clinical findings of the DBM in order to encourage interest in the prospects opened up by the DBM through innovative formulations of the vitamins and Melatonin and the use of biological molecules with a high degree of antitumoural efficacy and low toxicity such as Somatostatin and its analogues.
Available from: jnm.snmjournals.org
[Show abstract] [Hide abstract]
ABSTRACT: Radiolabeled peptides targeted against receptors on the cell surface have been shown to be remarkably specific and effective in the diagnosis and therapy of malignant disease. Much of the early work in this field took place outside the United States, but in recent years the research effort within the United States has accelerated. Most of the initial studies in the United States focused on somatostatin receptor ligands. (111)In-pentetreotide was approved in 1994 and has been used extensively in the diagnosis and management of a wide variety of neuroendocrine tumors, particularly carcinoid. This work was extended to (99m)Tc-labeled analogs, and the most successful, (99m)Tc-depreotide, was approved in 1999. This agent was found to be accurate in the diagnosis of lung cancer, but it was not particularly successful because it was supplanted by (18)F-FDG imaging with positron tomography. More recently, studies with (68)Ga-labeled somatostatin analogs were initiated in the United States. This effort was delayed relative to that in other parts of the world because of difficulty in obtaining the necessary generators and regulatory uncertainty, both of which are less of a problem currently. Several ligands are being developed to image melanoma through targeting of the melanocyte-stimulating hormone receptor. Other ligands are being developed to use the arginine-glycine-aspartate oligopeptide to target angiogenesis and to use bombesin analogs to target the gastrin-releasing peptide receptor for the diagnosis and potential therapy of prostate cancer. Peptide dimers that target 2 receptors simultaneously are also being constructed, potentially increasing the selectivity of the approach significantly. Radiopeptide therapy has been explored with these ligands, initially with high-dose (111)In-pentetreotide. This step has been followed by U.S. participation in several trials with (90)Y-, (177)Lu-, and (188)Re-labeled analogs. Some of these agents are now available clinically outside the United States, and it is important to design and conduct the appropriate trials so that this therapy can be offered within the United States.
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.