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Radioactive Iodine (radioactive + iodine)
Terms modified by Radioactive Iodine Selected AbstractsRecombinant Human Thyrotropin Administration Enhances Thyroid Uptake of Radioactive Iodine in Hyperthyroid CatsJOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 6 2008I. Van Hoek Background: Hyperthyroidism is the most diagnosed endocrine disorder in cats and radioiodine (131I) is the treatment of choice. The dose emission rate and radioactivity in urine, saliva, and on hair and paws are determined by the dose of administered 131I. A dose reduction of therapeutic 131I could possibly be achieved after recombinant human thyrotropin (rhTSH) administration as in humans with nodular goiter. Hypothesis: rhTSH will increase radioiodine uptake in hyperthyroid cats. Animals: Five hyperthyroid cats. Methods: Twenty-five micrograms rhTSH (day 1) or 2 mL 0.9% sodium chloride (NaCl) (day 9) was injected IV. One hour later, 11.4 ± 4.1 (mean ± SD) MBq 123I was injected IV. Radioactive iodine uptake (RAIU) was measured 6, 12, and 24 hours after rhTSH (RAIU-rhTSH) or NaCl (RAIU-blanco) injection. Blood samples for measurement of TT4 were taken before injection of rhTSH or NaCl (TT40) and at the time of imaging. Results: Percentages of RAIU-rhTSH (and RAIU-blanco) at 6, 12, and 24 hours after administration of rhTSH were 34 ± 18 (31 ± 21), 46 ± 20 (38 ± 18), and 47 ± 15 (36 ± 14). There was a statistically significant effect of rhTSH administration on RAIU (P= .043) but not on serum TT4 concentration. Baseline serum TT40 concentration influenced RAIU-rhTSH significantly at 6 hours (P= .037). Conclusion and Clinical Importance: The increased RAIU observed after rhTSH administration in hyperthyroid cats could lead to a lower therapeutic dose of 131I after rhTSH administration in hyperthyroid cats and decreased risk of environmental and owner contamination during and after hospitalization. [source] Retention of 125I-labeled recombinant human bone morphogenetic protein-2 by biphasic calcium phosphate or a composite sponge in a rabbit posterolateral spine arthrodesis modelJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 5 2002John Louis-Ugbo The purpose of this study was to characterize the retention kinetics of recombinant human bone morphogenetic protein-2 (rhBMP-2) applied to two calcium-based delivery matrices. Biphasic calcium phosphate (BCP) and a composite containing BCP in an absorbable collagen sponge (BCP/ACS) were evaluated using a spinal fusion model in rabbits. rhBMP-2 labeled with radioactive iodine (125I) was used as a tracer to assess in vivo retention of rhBMP-2 in the presence of these materials (nine animals per material studied). Over a 36 day study period, animals were assessed for the following: percent administered dose retained at the implant site as measured by scintigraphic imaging (counting) with a gamma camera (all animals), radiography of the implant site (all animals), radioactivity in blood and plasma (all animals), and radioactivity in the urine and feces (three animals for each material). Radioactivity data were corrected for the decay of 125I and the attenuation between the implant in vivo and the gamma camera. Differences observed between the two materials for the area under the retention vs. time profile (AUC; 988%day for BCP vs. 1070%day for BCP/ACS, p = 0.57) and the mean residence time (MRT; 10.2 days for BCP vs. 7.6 days for BCP/ACS, p = 0.06) were not statistically significant. Initial retention/incorporation of rhBMP-2 was slightly higher for rhBMP-2/BCP/ACS than for rhBMP-2/BCP (96.8% vs. 86.0%, p lt; 0.05). Animals receiving rhBMP-2/BCP showed a longer terminal retention half-life (t1/2) than did those receiving rhBMP-2/BCP/ACS (7.5 vs. 4.5 days, p < 0.05). The urinary radioactivity recovery data supported the data obtained by scintigraphy. Over the 36 day collection period, essentially complete recovery of radioactivity (dose) in urine was observed for rhBMP-2/BCP and rhBMP-2/BCP/ACS and the majority of the radioactivity (approximately 95%) was soluble in trichloroacetic acid, suggesting extensive catabolism of rhBMP-2 before renal excretion. Fecal recovery of radioactivity was low, approximately 2,3%. In conclusion, rhBMP-2 was retained at the implant site when delivered with either BCP or BCP/ACS based on mean residence time and area under the retention curve vs. time profile. Use of these matrices resulted in detectable rhBMP-2 levels at the surgical site for over a week in contrast to data reported with several other matrices that lasted less time. Systemic catabolism and elimination of the rhBMP-2 was extensive and systemic presence of the protein was negligible. © 2002 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved. [source] Survival in patients with papillary thyroid cancer is not affected by the use of radioactive isotopeJOURNAL OF SURGICAL ONCOLOGY, Issue 1 2007Yale D. Podnos MD Abstract Introduction Papillary cancer is the most common neoplasm of the thyroid. The mainstay of treatment is thyroidectomy, but most patients are additionally treated with radioactive iodine (RAI). Its utility is controversial. This study seeks to determine whether RAI use affects patient outcome and to identify specific cohorts of patients that benefit from its use. Methods The Surveillance, Epidemiology, and End Results (SEER) database is a large-scale sample of approximately 14% of the US population. It was used to identify patients with papillary carcinoma of the thyroid. Statistical analyses were used to compare prognostic factors such as lymph node status, age, tumor size, and treatment with RAI. Results A total of 14,545 patients were identified in SEER as having papillary cancer of the thyroid. Multivariate analysis showed significantly worse outcome in patients with age>45 years, tumor size >2 cm, lymph node disease, and distant metastases. Multivariate analysis failed to show RAI significantly affecting mortality. Survival between those not treated with RAI was similar to those whose treatment included it (P,=,0.9176). Subgroup analysis identified patients older than 45 years with primary tumors >2 cm and disease in the lymph nodes with distant metastatic disease as the only group positively affected by RAI. Conclusions Despite its widespread use in the treatment of well-differentiated papillary cancer of the thyroid, RAI only affects a survival advantage in older patients with large primary tumors involving the lymph nodes and with distant spread. Treating other patient groups is costly and offers no improvement in outcome. J. Surg. Oncol. 2007; 96:3,7. © 2007 Wiley-Liss, Inc. [source] Management of well-differentiated thyroid carcinoma presenting within a thyroglossal duct cystJOURNAL OF SURGICAL ONCOLOGY, Issue 3 2002Snehal G. Patel MD Abstract Background and Objective Well-differentiated thyroid carcinoma (WDTC) is diagnosed in approximately 1.5% of thyroglossal duct cysts (TGDC). No clear consensus exists regarding further management after adequate excision of the cyst, especially the role of total thyroidectomy and postoperative radioactive iodine therapy. The current review was undertaken in an attempt to clarify these issues. Methods Demographic, clinical, tumor, treatment, pathology, and outcome data on 57 eligible patients reported in recent literature were pooled together with 5 patients treated at our institution for this analysis. Results A Sistrunk operation was performed for resection of the thyroglossal duct cyst in the majority (90%) of patients. Histologic examination of the tumor in the cyst revealed that papillary carcinoma was the most frequent (92%) histologic type. A total thyroidectomy was performed consequent to the diagnosis of thyroglossal duct cyst carcinoma in approximately half of the 62 patients. A malignant tumor was reported in 27% of the thyroidectomy specimens. Postoperative radioactive iodine therapy was administered in 16 (26%) patients. With a median follow-up of 71 months (range 1,456 months), the 5- and 10-year Kaplan,Meier overall survival was 100 and 95.6%, respectively. There were no disease-related deaths reported in any of the patients. Univariate analysis revealed that the only significant predictor of overall survival was the extent of primary surgery for the thyroglossal cyst. The addition of total thyroidectomy to Sistrunk operation did not have a significant impact on outcome (P,=,0.1). Patients treated with postoperative radioactive iodine (RAI) fared significantly worse than those that did not need RAI, which may be explained by the fact that this modality would generally be used in patients with higher risk tumors. Conclusions The Sistrunk operation is adequate for most patients with incidentally diagnosed TGDC carcinoma in the presence of a clinically and radiologically normal thyroid gland. Results of adequate excision using the Sistrunk operation are excellent and the concept of risk-groups should be used to identify patients, who would benefit from more aggressive treatment. J. Surg. Oncol. 2002;79:134,139. © 2002 Wiley,Liss, Inc. [source] Survival impact of treatment options for papillary microcarcinoma of the thyroidTHE LARYNGOSCOPE, Issue 10 2009Harrison W. Lin MD Abstract Objectives/Hypothesis: Evaluate the impact of medical and surgical interventions on the survival of patients with papillary microcarcinoma (PMC) of the thyroid, a common tumor with an increasing worldwide incidence. Study Design: Cross-sectional population analysis of a prospectively maintained database. Methods: Cases of nonmetastatic PMC treated with cancer-directed surgery with or without postoperative radioactive iodine (RAI) therapy were extracted from the Surveillance, Epidemiology and End Results Database (1988,2005). Kaplan-Meier disease-specific survival (DSS) and overall survivals were compared according to extent of thyroidectomy and use of RAI therapy. Cox regression analysis was performed to determine the influence of these factors on survival. Results: A total of 7,818 cases of PMC were identified. Overall actuarial survival rates at 10 and 15 years were 96.6% and 96.3%, respectively. DSS was 99.9% at both time intervals, with a total of 10 thyroid cancer-related deaths. There were no significant differences in DSS for patients who underwent total thyroidectomy, near-total/subtotal thyroidectomy, or lobectomy (P = .239). DSS for patients receiving RAI therapy was not significantly different than that of patients who did not (P = .504). On multivariate analysis, only increasing age at diagnosis, successfully predicted poor DSS (P = .001), whereas gender (P = .481), use of RAI therapy (P = .633), and extent of thyroidectomy (P = .104) did not. Conclusions: PMC carries an excellent prognosis with respect to both overall and disease-specific survival that is independent of surgical extent and the use of RAI therapy. An isolated, fine-needle,aspiration proven unilateral PMC focus in a patient lacking evidence of metastatic disease may be treated with lobectomy alone. Laryngoscope, 2009 [source] Health-Related Quality-of-Life Study in Patients With Carcinoma of the Thyroid After Thyroxine Withdrawal for Whole Body ScanningTHE LARYNGOSCOPE, Issue 11 2006Sin-Ming Chow FRCR Abstract Objectives/Hypothesis: The authors studied the change of health-related quality of life (HR-QOL) in patients with differentiated thyroid carcinoma (DTC) with thyroxine (T4) withdrawal in preparation for whole body radioactive iodine scanning. Study Design: Seventy-eight patients with DTC and history of radioactive iodine (RAI) ablation were prospectively recruited. They completed the Functional Assessment of Cancer Treatment-General (FACT-G) questionnaire on weeks 0, 2, and 4 after T4 withdrawal with corresponding checking of serum thyroid-stimulating hormone (TSH). Results: Overall, 74.5% (58 of 78) of patients completed all FACT-G. Comparing FACT-G scores at weeks 0 and 4, "physical" (P < .001), "social" (P = .04), and "emotional" (P = .047) aspects were lowered as well as "total" HR-QOL (P = .001). However, the "functional" domain of HR-QOL was not affected (P = .14). Comparing FACT-G scores at week 0 and 2, we found that "physical" (P = .049) and "total" (P = .05) HR-QOL were affected early (in the first 2 weeks) in T4 withdrawal. Comparison of week 2 and 4 showed that in the later half of the withdrawal period, "physical" (P = .001), "emotional" (P = .02), and "total" FACT-G scores (P = .002) were affected. Mean TSH level (in mIU/L) increased gradually: 2.8 (week 0), 42.8 (week 2), 97 (week 3), and 153 (week 4). The percentage of patients attaining TSH level of >30 mIU/L were 55% (week 2), 96.2% (week 3), and 100% (week 4). Conclusions: HR-QOL declines with time of T4 withdrawal. The impact is more severe in the later period of T4 withdrawal. In 3 weeks, 96.2% of our patients attained TSH level of 30 mIU/L. To minimize the impact on HR-QOL, duration of T4 withdrawal can be decreased to 3 weeks. [source] Controversies in the Management of Thyroid NoduleTHE LARYNGOSCOPE, Issue 2 2000Ashok R. Shaha MD Abstract Few subjects in surgery have generated as much controversy as the management of thyroid nodule. The controversial issues include classification and histology, diagnostic evaluation including needle biopsy, indications for surgery, management of incidentalomas of the thyroid, the role of frozen section, extent of thyroidectomy, management of neck nodes, the role of suppressive therapy, the use of radioactive iodine, and appropriate follow-up. The two major issues in relation to the controversies are diagnostic workup and extent of thyroidectomy. Whenever the issue related to extent of thyroidectomy is discussed, there are two strong groups believing in total thyroidectomy or less than total thyroidectomy. This has generated considerable debate and panel discussions, and this article reviews this on-going debate. [source] Clinical management and outcome of papillary and follicular (differentiated) thyroid cancer presenting with distant metastasis at diagnosis,CANCER, Issue 7 2007Elliot Sampson BSc Abstract BACKGROUND. Differentiated thyroid cancer has a good prognosis and only rarely presents with distant metastasis at diagnosis. The clinical outcome of this presentation was assessed with respect to survival and factors that may determine prognosis. METHODS. A retrospective review was undertaken of patients with stage M1 differentiated thyroid cancer at presentation (n = 49), referred from 1980,2000 at a single institution. RESULTS. The median age was 68 (range, 17,90), with 69% females. The initial site(s) of metastasis were lung only, 45%, bone only, 39%, other single site, 4%, and multiple sites, 12%. Histology: papillary, 51%, follicular, 49%. Initial treatment(s) included: thyroidectomy, 82%, radioactive iodine (RAI), 88%, excision of metastasis, 29%, radiotherapy, 47%, and chemotherapy, 6%. With a median follow-up time of 3.5 years, 25 patients are alive (51%) and 24 died (49%), with 3-year and 5-year actuarial survivals of 69% and 50%, respectively. Only a minority of patients (4/25, 16%) had no clinical evidence of disease at last follow-up. Most deaths (17/24, 71%) were due to progressive cancer. Prognosis was associated with age, site of metastasis, histology, and iodine avidity of the metastasis. Patients aged ,45 (n = 8) had a 3-year survival of 100%, versus 62% for those age > 45 years (P = .001). The 3-year survival for lung only versus bone only metastasis was 77% versus 56% (P = .02); for papillary versus follicular carcinoma, 75% versus 62% (P = .006); for iodine-avid disease (n = 29) versus not avid (n = 14), 82% versus 57% (P = .02), respectively. In multivariate analysis after adjusting for age, only histology and iodine avidity remained significant for survival. The hazard ratio for follicular histology was 3.7 (95% confidence interval [CI], 1.1,12.1, P = .03), and for tumors not avid for iodine, 3.4 (95% CI, 1.2,9.2, P = .02). CONCLUSIONS. The data support the aggressive management of patients presenting with stage M1 thyroid cancer, with thyroidectomy and RAI. Complete clinical eradication of disease was rarely seen, and 50% of patients survived for more than 5 years. Young patients with papillary tumors and/or iodine-avid disease have an even better prognosis. Cancer 2007. © 2007 American Cancer Society. [source] Increased cancer incidence after radioiodine treatment for hyperthyroidismCANCER, Issue 10 2007Saara Metso MD Abstract BACKGROUND. Concerns remain about risk of cancer after radioactive iodine (RAI) treatment for hyperthyroidism, especially in organs that concentrate iodine. The objective was to assess the long-term cancer risk from RAI treatment for hyperthyroidism. METHODS. A total of 2793 hyperthyroid patients treated with RAI at Tampere University Hospital between 1965 and 2002, and 2793 age- and sex-matched reference subjects were followed for an average of 10 years through the Finnish Cancer Registry. RESULTS. Cancer incidence among hyperthyroid patients treated with RAI was higher than in the population-based control group (118.9 vs 94.9 per 10,000 person-years, rate ratio [RR], 1.25; 95% confidence interval [CI]: 1.08,1.46). Furthermore, incidence of stomach (RR, 1.75, 95% CI: 1.00,3.14), kidney (RR, 2.32; 95% CI: 1.06,5.09), and breast (RR, 1.53; 95% CI: 1.07,2.19) cancer was increased among RAI-treated patients. The relative risk of cancer increased with higher RAI dose administered. The increase in cancer incidence was statistically significant in patients treated at the age of 50,59 (RR, 1.44; 95% CI: 1.05,1.97) or older than 70 years (RR, 1.39; 95% CI: 1.05,1.82). There was a 5-year latent period after the RAI treatment before the cancer incidence began to differ between the RAI-treated hyperthyroid patients and the control group. CONCLUSIONS. Cancer incidence, especially cancer of the stomach, kidney, and breast, was higher in patients treated with RAI for hyperthyroidism. Cancer 2007. © 2007 American Cancer Society. [source] Prognostic factors in patients with Hürthle cell neoplasms of the thyroidCANCER, Issue 5 2003Luis Lopez-Penabad M.D. Abstract BACKGROUND Hürthle cell neoplasms, often considered a variant of follicular thyroid neoplasms, represent 3% of thyroid carcinomas. Only a handful of publications have focused on the biologic behavior, prognostic factors, and treatment outcomes of Hürthle cell carcinoma. The objective of the current study was to identify the clinical and pathologic features of Hürthle cell carcinomas that predict disease progression or death. METHODS The authors reviewed medical records of patients who were treated for Hürthle cell carcinoma (HCC) and Hürthle cell adenoma (HCA) at The University of Texas M. D. Anderson Cancer Center from March 1944 to February 1995, including follow-up information. The pathologic diagnosis was confirmed by one of the authors. RESULTS The authors identified 127 patients with Hürthle cell neoplasms, 89 patients with HCC and 38 patients with HCA. Seven patients with HCC had foci of anaplastic thyroid carcinoma. Survival for this subgroup was worse compared with the overall group and was analyzed separately. The HCC group was significantly older (age 51.8 years vs. age 43.1. years) and had larger tumors (4.3 cm vs. 2.9 cm) compared with the HCA group. No differences were seen in gender or previous radiation exposure. Forty percent of patients in the HCC group died of thyroid carcinoma, whereas no patients in the HCA group died of the disease. There has been no improvement in all-cause and disease specific mortality in the past 5 decades for patients with these neoplasms. Conventional staging systems predicted mortality with minor differences. Of the patients with known metastasis, 38% showed radioiodine uptake. Univariate analysis identified older age, higher disease stage, tumor size, extraglandular invasion, multifocality, lymph node disease, distant metastasis, extensive surgery, external beam radiation therapy, and chemotherapy as factors that were associated with decreased survival. Tumor encapsulation was associated with improved survival. Although radioactive iodine treatment had no overall effect on survival, subgroup analysis showed that patients who received radioactive iodine for adjuvant ablation therapy had better outcomes compared either with patients who did not receive radioactive iodine or with patients who received radioactive iodine as treatment for residual disease. Multivariate analysis indicated that older age and larger tumor size predicted worse survival through an association with worse behaving tumors (multifocal, less encapsulated, and with extraglandular invasion). The decreased survival in patients with lymph node metastases may be explained by its association with distant metastases. The association of extensive surgery, external beam radiation therapy, and chemotherapy with worse survival also disappeared once those factors were analyzed together with other prognostic factors, such as distant metastases. CONCLUSIONS Several clinical and pathologic prognostic factors were identified in patients with HCC and HCA. Older age and larger tumor size predicted reduced survival. Radioactive iodine therapy may confer a survival benefit when it is used for adjuvant ablation therapy, but not when residual disease is present. The authors could not demonstrate a survival benefit for the use of extensive surgery, external beam radiation therapy, or chemotherapy. Cancer 2003;97:1186,94. © 2003 American Cancer Society. DOI 10.1002/cncr.11176 [source] Pancreatic fate of a 125I-labelled mouse monoclonal antibody directed against pancreatic B-cell surface ganglioside(s) in control and diabetic ratsCELL BIOCHEMISTRY AND FUNCTION, Issue 2 2001Laurence Ladri Abstract The possible use of a mouse monoclonal antibody directed against rat pancreatic B-cell surface ganglioside(s) and labelled with radioactive iodine for selective imaging of the endocrine pancreas by a non-invasive procedure was investigated by following its pancreatic fate in experiments conducted either in vitro by incubation of rat isolated pancreatic islets, acinar tissue and pancreatic pieces or in vivo after intravenous injection of the 125I-labelled antibodies ([125I],-G). Although the binding of [125I],-G per µg protein was about one order of magnitude higher in isolated islets than in acinar tissue, no significant difference was detected when comparing pancreatic pieces or isolated islets from control animals and rats rendered diabetic by one or two prior administrations of streptozotocin (STZ rats). Likewise, except in one set of experiments, no significant difference was found between control animals and STZ rats, when measuring the radioactive content of the pancreatic gland, relative to that of plasma, 1,4 days after the intravenous injection of [125I],-G. These findings indicate that under the present experimental conditions, the mouse monoclonal antibody labelled with radioactive iodine does not appear to be a promising tool for selective imaging of the endocrine pancreas, e.g. by single photon emission computerized tomography. Copyright © 2001 John Wiley & Sons, Ltd. [source] 3144: Cataract formation after incorporation of radioactive iodineACTA OPHTHALMOLOGICA, Issue 2010C DALKE Purpose The ocular lens is one of the most radiosensitive organs in mammals and a pathological sign after exposure to ionising radiation is the formation of cataracts. We generated a mouse model to mimic the situation after the accident in the Chernobyl power plant. Methods Pregnant and nursing FBV-mice were treated with iodine131 for diaplacentar and galactogen transfer to the litter. The offspring which incorporated the radioiodine were examined for lens opacities at the age of 6 and 12 months. Iodine131 is a beta radiation emitting nuclide with a short half live of 8 days. Mothers were injected twice with 100 kBq I-131, on day 14 post conception and day 6 post natal. Cataracts were investigated at 6 and 12 months of age using a slit lamp. Results Depending on the litter size and weight, a single progeny incorporates between 8 to 14 % of entire activity. More than 50% of the injected activity is transmitted from the mother to the entire offspring. Iodine is accumulated in the thyroid and an average thyroid dose of 3.7 Gy was calculated. Because of the short distance between the thyroid and the eye, a lens dose of 0.5 Gy was estimated. In the FBV mice, we observed at the age of 6 months two cataracts among 15 irradiated lenses (13%), but none among 7 unirradiated controls. At the age of 12 months, almost all lenses showed cortical cataracts in both groups. However, there were 17 nuclear cataracts among 66 irradiated lenses (25%), but only 1 among 16 controls (6%). Conclusion These preliminary data indicate that this method is sensitive enough to detect the cataract-causing potential of low-dose ionizing radiation in the mouse. However, for detailed analysis larger cohorts and quantification of the data are necessary. [source] | |||||||||||||