Radioactive Iodine 131I Research Articles

Atorvastatin-loaded cubosome: a repurposed targeted delivery systems for enhanced targeting against breast cancer

Cancer ranks as one of the most challenging illnesses to deal with because progressive phenotypic and genotypic alterations in cancer cells result in resistance and recurrence. Thus, the creation of novel medications or alternative therapy approaches is mandatory. Repurposing of old drugs is an attractive approach over the traditional drug discovery process in terms of shorter drug development duration, low-cost, highly efficient and minimum risk of failure. In this study Atorvastatin, a statin drug used to treat abnormal cholesterol levels and prevent cardiovascular disease in people at high risk, was introduced and encapsulated in cubic liquid crystals as anticancer candidate aiming at sustaining its release and achieving better cellular uptake in cancer cells. The cubic liquid crystals were successfully prepared and optimized with an entrapment effieciency of 73.57% ±1.35 and particle size around 200 nm. The selected formulae were effectively doped with radioactive iodine 131I to enable the noninvasive visualization and trafficking of the new formulae. The in vivo evaluation in solid tumor bearing mice was conducted for comparing131I-Atorvastatin solution,131I-Atorvastatin loaded cubosome and 131I-Atorvastatin chitosan coated cubosome. The in vivo biodistribution study revealed that tumor radioactivity uptake of 131I-Atorvastatin cubosome and chitosan coated cubosome exhibited high accumulation in tumor tissues (target organ) scoring ID%/g of 5.67 ± 0.2 and 5.03 ± 0.1, respectively 1h post injection compared to drug solution which recorded 3.09 ± 0.05% 1h post injection. Concerning the targeting efficiency, the target/non target ratio for 131I-Atorvastatin chitosan coated cubosome was higher than that of 131I-Atorvastatin solution and 131I ATV-loaded cubosome at all time intervals and recorded T/NT ratio of 2.908 2h post injection.

Post-radiation lesions of the salivary glands after radioiodine therapy: features of the clinical course

To date, thyroid diseases are one of the most common pathologies of the endocrine system and are an urgent medical and social problem. In order to treat and diagnose differentiated thyroid cancer, thyrotoxic goiter, and diffuse toxic goiter, radioiodine therapy is used in combination with other methods (surgery, hormone therapy). Lesions of the salivary glands that occur after radiotherapy are associated with the ability of large salivary glands to concentrate iodine in ductal cells. The accumulation of radioactive iodine I131 has an adverse radiation effect on the salivary glands, which leads to damage to the tissues of the glands of varying degrees of intensity.Background. Despite the large number of publications devoted to this problem, the clinical and laboratory characteristics of radioiodosialadenitis remain incomplete and often contradictory. In this regard, the study of this topic does not lose its relevance.Materials and methods. As a result of the examination of 45 patients after radiooderpia, with a clinical-radiological examination, a group of patients (n = 12), with a lack of a secret during visual examination and contrast of one or more salivary glands, is probably associated with irreversible changes in the salivary glands, was identified and described in this article.Results. Different combinations of damage to one or more salivary glands have been identified, reducing the level of quality of life of patients in this group of patients. When examining the salivary glands and conducting differential diagnostics, various combinations of examination methods must be used.Conclusions. The side effect of the effects of radioid therapy on the salivary glands is characterized by a wide spectrum of the involvement of the salivary glands up to a decrease in the functional activity and atrophy of the salivary glands, however, adverse consequences are not always dose-dependent. The results of the methods obtained do not exclude, but complement each other, which allows you to fully evaluate structural and functional changes in salivary glands. The negative effects of radionuclide therapy on the salivary glands affects the quality of life of patients.

Impact of (nano ZnO/multi-wall CNTs) prepared by arc discharge method on the removal efficiency of stable iodine 127I and radioactive iodine 131I from water

Radioactive iodine isotopes especially 131I are used for diagnosis and treatment of different types of cancer diseases. Due to the leak of radioactive iodine into the patient’s urine in turn, the wastewater would be contaminated, so it is worth preparing a novel adsorption green material to remove the radioactive iodine from wastewater efficiently. The removal of 127I and 131I contaminants from aqueous solution is a problem of interest. Therefore, this work presents a new study for removing the stable iodine 127I− and radioactive iodine 131I from aqueous solutions by using the novel nano adsorbent (Nano ZnO/MWCNTs) which is synthesized by the arc discharge method. It is an economic method for treating contaminated water from undesired dissolved iodine isotopes. The optimal conditions for maximum removal are (5 mg/100 ml) as optimum dose with shacking (200 rpm) for contact time of (60 min), at (25 °C) in an acidic medium of (pH = 5). After the adsorption process, the solution is filtrated and the residual iodide (127I−) is measured at a maximum UV wavelength absorbance of 225 nm. The maximum adsorption capacity is (15.25 mg/g); therefore the prepared nano adsorbent (Nano ZnO/MWCNTs) is suitable for treating polluted water from low iodide concentrations. The adsorption mechanism of 127I− on to the surface of (Nano ZnO/MWCNTs) is multilayer physical adsorption according to Freundlich isotherm model and obeys the Pseudo-first order kinetic model. According to Temkin isotherm model the adsorption is exothermic. The removal efficiency of Nano ZnO/MWCNTs for stable iodine (127I−) from aqueous solutions has reached 97.23%, 89.75%, and 64.78% in case of initial concentrations; 0.1843 ppm, 0.5014 ppm and 1.0331 ppm, respectively. For the prepared radio iodine (131I−) solution of radioactivity (20 µCi), the dose of nano adsorbent was (10 mg/100 ml) and the contact time was (60 min) at (pH = 5) with shacking (200 rpm) at (25 °C). The filtration process was done by using a syringe filter of a pore size (450 nm) after 2 days to equilibrate. The removal efficiency reached (34.16%) after the first cycle of treatment and the percentage of residual radio iodine was (65.86%). The removal efficiency reached (94.76%) after five cycles of treatment and the percentage of residual radio iodine was (5.24%). This last percentage was less than (42.15%) which produces due to the natural decay during 10 days.

Evaluacija metode 99Tcm-DTPA orbit SPECT/CT u kombinaciji sa testom funkcije štitaste žlezde u terapiji radioaktivnim jodom I-131 kod pacijenata sa hipertiroidizmom koji je povezan sa oftalmopatijom

Background: Thyroid-associated ophthalmopathy (TAO) is an autoimmune response to inflammation of the thyroid and orbital tissue. This research evaluated the efficacy of 99Tcm-DTPA orbital SPECT/CT combined with thyroid function test in radioactive iodine I-131 (RAI) treatment of TAO-hyperthyroidism. Methods: We retrospectively studied clinical activity score (CAS), blood thyrotropine (TSH), free triiodothyronine (FT3), free thyroxine (FT4), thickness of extra-ocular muscle (EOM), and uptake rate (UR) of 99Tcm-DTPA orbital SPECT/CT of 43 patients after 6 months of treatment with 20 mCi RAI. Parameters were compared before and after RAI in patients assessed as effectively treated (normal thyroid function or hypothyroidism), and correlations between blood FSH, FT3, FT4, thickness of EOM, and UR were analyzed after treatment. Results: After RAI, 35 cases (70 eyes, 81.4%) had normal or hypothyroidism, and 8 cases (16 eyes, 18.6%) had hyperthyroidism. Compared with the patients who failed treatment, effectively treated patients had lower CAS, FT3, FT4, and UR and higher blood TSH. In patients with effective treatment, UR of the inferior rectus muscle was positively correlated with FT3 and FT4. Adverse RAI outcomes were associated with smoking and higher iodine-thyroid iodine uptake before treatment. Conclusions: Combined with TSH, FT3, and FT4 levels, the reduction of 99Tcm-DTPA orbital SPECT/CT UR also indicates an improvement in the disease course of patients. The UR of the inferior rectus muscle can be an objective index to evaluate the curative effect of TAO patients.

Predictive Factors for the Efficacy of Radioactive Iodine Treatment of Graves’ Disease

Objective: The utilization of radioactive iodine‐131I (RAI) has long been established as a cost‐effective and conventional treatment for managing Graves’ disease (GD). However, the accurate prediction of the clinical response to RAI treatment remains difficult. The successful resolution of GD through RAI therapy is typically characterized by the induction of hypothyroidism or euthyroidism. Thus, the principal aim of this study was to identify plausible predictors of RAI efficacy in the treatment of GD.Methods: The clinical data of 613 GD patients, who underwent RAI treatment for the first time, were retrospectively analyzed, including age, gender, duration of hyperthyroidism, presence or absence of ocular signs, thyroid volume, thyroid weight, thyroid function (FT3, FT4, and TSH), radioactive iodine uptake (RAIU) at 2 h/6 h/24 h (2‐h/6‐h/24‐h RAIU) prior to RAI treatment, the highest RAIU (RAIUmax), and administered activity of 131I and 131I activity per gram of thyroid tissue. Success of RAI treatment was defined as achieving hypothyroidism or euthyroidism for more than 1 year after the initial treatment. Univariate and multivariate logistics regression analyses were conducted to identify factors that influence the efficacy of RAI treatment for GD. And at last, based on the results of the multivariate logistic regression analysis, a nomogram model was established.Results: In this study, the success rate of RAI treatment for GD was 91.2% (559/613). Univariate analysis demonstrated that several factors, including age (p = 0.005), thyroid volume (p = 0.001), thyroid‐stimulating hormone (TSH, p = 0.042), ratio of RAIU at 6 h to 24 h (6‐h/24‐h RAIU, p = 0.048), total 131I activity (p = 0.026), and 131I activity per gram of thyroid tissue (p = 0.001), were significantly associated with treatment outcome. Multivariate logistic regression analysis indicated thyroid volume and 131I activity per gram of thyroid tissue as significant independent predictors of radioactive iodine therapy (RIT) efficacy. The area under the ROC curve of the established nomogram model was 0.769 (95% confidence interval [CI]: 0.692–0.846), indicating that the model has good discriminatory ability.Conclusion: Calculated‐dose RAI is effective in the treatment of GD. The smaller thyroid volume and the higher 131I activity per gram of thyroid tissue are predictors of RAI efficacy in the treatment of GD.

Brain nanotargeted [131I] I-Rolapitant as a model for brain imaging: Intranasal formulation, radiolabelling, biodistribution, and comparative study

The goal of this study was to create a novel single-photon emission computed tomography (SPECT) probe that would enable the visualization of neurokinin-1 NK1 receptor systems in the brain for the precise diagnosis and follow-up of many brain-related disorders. Rolapitant (RT), a selective, high-affinity NK1 receptor antagonist, was successfully radiolabelled with the radioactive Iodine 131I with high radiolabelling efficiency after refining several parameters impacting the radiolabelling process' efficiency. To improve the radiopharmaceutical's bioavailability, and brain delivery and boost the diagnostic yield of the novel radiopharmaceutical formulation, [131I] I-Rolapitant was successfully fabricated in a spanlastic nanovesicle (SNV) formulation with a convenient hydrodynamic size, a reasonable biocompatibility profile, and feasible in vitro stability. The selected formula was evaluated comparatively in a parallel biodistribution study in contrast to RT intravenous and intranasal solutions comparing brain targeting efficiency. The in vivo study revealed a high brain uptake (6.740 ± 0.09% ID/g) 2 h post-administration which was 3fold greater than the brain uptake of [131I] I-Rolapitant intravenous solution. Regarding the Brain/Blood Ratio, [131I] I-Rolapitant SNV outperformed RT intravenous and intranasal solutions, with a maximum ratio of 2.03 reached 24 h after administration. These results suggest that the proposed spanlastic nanoform could be regarded as a promising drug vector for the transnasal delivery of radiopharmaceuticals to the brain.

The use of single-timepoint images to link administered radioiodine activity (MBq) to a prescribed lesion radiation-absorbed dose (cGy): a regression-based prediction interval tool for the management of well-differentiated thyroid cancer patients

PurposeTo introduce a biomarker-based dosimetry method for the rational selection of a treatment activity for patients undergoing radioactive iodine 131I therapy (RAI) for metastatic differentiated thyroid cancer (mDTC) based on single-timepoint imaging of individual lesion uptake by 124I PET.MethodsPatients referred for RAI therapy of mDTC were enrolled in institutionally approved protocols. A total of 208 mDTC lesions (in 21 patients) with SUVmax > 1 underwent quantitative PET scans at 24, 48, 72, and 120 h post-administration of 222 MBq of theranostic NaI-124I to determine the individual lesion radiation-absorbed dose. Using a general estimating equation, a prediction curve for biomarker development was generated in the form of a best-fit regression line and 95% prediction interval, correlating individual predicted lesion radiation dose metrics, with candidate biomarkers (“predictors”) such as SUVmax and activity in microcurie per gram, from a single imaging timepoint.ResultsIn the 169 lesions (in 15 patients) that received 131I therapy, individual lesion cGy varied over 3 logs with a median of 22,000 cGy, confirming wide heterogeneity of lesion radiation dose. Initial findings from the prediction curve on all 208 lesions confirmed that a 48-h SUVmax was the best predictor of lesion radiation dose and permitted calculation of the 131I activity required to achieve a lesional threshold radiation dose (2000 cGy) within defined confidence intervals.ConclusionsBased on MIRD lesion-absorbed dose estimates and regression statistics, we report on the feasibility of a new single-timepoint 124I-PET-based dosimetry biomarker for RAI in patients with mDTC. The approach provides clinicians with a tool to select personalized (precision) therapeutic administration of radioactivity (MBq) to achieve a desired target lesion-absorbed dose (cGy) for selected index lesions based on a single 48-h measurement 124I-PET image, provided the selected activity does not exceed the maximum tolerated activity (MTA) of < 2 Gy to blood, as is standard of care at Memorial Sloan Kettering Cancer Center.Trial registrationNCT04462471, Registered July 8, 2020.NCT03647358, Registered Aug 27, 2018.

Radioactive iodine in the treatment of Graves' disease: history and modern concept of radionuclide therapy

Radioactive iodine 131I is a theranostic isotope used both for diagnosis and therapy of benign thyroid diseases and thyroid cancer for 85 years. The formation of nuclear medicine is closely linked with the use of 131I. The history of radioiodine therapy began in 1941, when endocrinologist Saul Hertz for the first time used 131I to treat patients with Graves' disease. Since 1946 radioactive iodine 131I became widely available, and its effectiveness became public knowledge after reports on thyrotoxicosis treatment published in the Journal of the American Medical Association by multidisciplinary groups of scientists - physicists and endocrinologists. In 1951, isotope 131I became the first Food and Drug Administration approved RP for the treatment of thyroid disorders. Around the same time on the basis of the First Moscow Medical Institute studies on the use of radioiodine isotopes in patients with thyrotoxicosis began. The head of the Soviet group on the studying of radioactive iodine was the physician-scientist Vera Georgievna Spesivtseva. The research works of medical physicists Edith Quimby and Leonidas Marinelli in optimizing therapeutic strategies using radioactive substances in the late 1940s and the wording of the ALARA (As Low As Reasonably Achievable) principle of minimizing exposure of ionizing radiation by the International Commission on Radiological Protection in 1954 contributed to the greater introduction of radionuclides into the medicine.

Abstract #1184631: Persistent Azoospermia Following Radioactive Iodine I-131 Therapy for Thyroid Cancer in a Previously Fertile Male

Decreased sperm counts and infertility are known complications following radiation therapy, but are not commonly seen as a side effect of radioactive iodine (RAI) I-131 treatment for thyroid cancer. When present after RAI I-131, these effects are usually transient and typically resolve within one year following treatment. It is rare for a patient to experience persistent azoospermia with commonly used thyroid carcinoma treatment doses, especially in the absence of fertility impairment prior to RAI exposure.

Treatment of Graves’ Disease With a Combination of Low Iodine Diet and Potassium Iodide Plus Radioactive Iodine Treatment

Introduction: Graves’ disease (GD) is usually treated with radioactive iodine I131 (RAI), thionamide or surgery. Of these, RAI remains the safest and most efficacious treatment. We report 3 patients with GD who were treated with low iodine diet (LID), followed by RAI and subsequent potassium iodide (SSKI) administration.Case series:Patient 1 - A 50-year-old male presented with weight loss, heat intolerance and palpitations. Physical examination: HR 120 bpm, BP 110/80mmHg, no evidence of thyroid orbitopathy. Thyroid: 50 grams diffusely enlarged and brisk DTR. Lab findings: TSH 0.001, FT4 4.2, total T3 410, TSI 172. A thyroid scan revealed diffuse uptake 72% at 4-hours. He was diagnosed with GD and treated with methimazole. Three weeks later a CBC showed an absolute neutrophil count 820. After discontinuing methimazole, he was placed on prednisone 40mg daily and LID. Two weeks later (24-hours urine iodine <50 mcg), he received 15mCi I131. 72 hours later he was administered SSKI one drop BID for 3 days. Four weeks after RAI, TFT was normal. Two months later, he required levothyroxine treatment for hypothyroidism. Patient 2 - A 23-year-old female presented with weight loss and nervousness. Physical examination revealed HR 110 bpm, BP 100/70 mmHg, no thyroid orbitopathy, a diffusely enlarged thyroid. Serum TSH <0.005, FT4 3.9, total T3 398, TSI 149. Thyroid uptake showed 70% at 24-hours. Patient was started on methimazole and atenolol. Four weeks later she developed severe generalized erythematous rash. After treating with prednisone for one week she was placed on LID and treated with 15 mCi I131. Six weeks later TSH was 0.4 with a free T4 of 1.8 and four months later she required levothyroxine therapy for hypothyroidism. Patient 3 - A 40-year-old male presented with atrial fibrillation and hyperthyroidism. Patient received treatment for atrial fibrillation and physical examination confirmed heart rate 78 (on treatment), no evidence of thyroid orbitopathy, and diffusely enlarged thyroid. Serum TSH <0.005, FT4 3.1, total T3 298, TSI 231. Thyroid scan was consistent with GD with a 24-hr uptake of 62%. He refused to take methimazole due to fear of adverse side effects. After placing him on prednisone along with LID for 2weeks, he was treated with I131 15 mCi. 72 hours later he received SSKI one drop BID for 3 days. Prednisone was discontinued 2 weeks later. Six weeks following treatment, TSH was 1.1 with FT4 1.32. Patient remained euthyroid for the next 12 months of follow up. Discussion: LID given before RAI therapy has a potential of depleting total iodine pool which can increase the I131 uptake in the thyroid gland and facilitate β-radiation to the thyroid gland. SSKI following RAI can improve retention of I131 in the thyroid gland and reduce the recycling of radioactivity between the thyroid and the blood. In summary, a LID prior to RAI and SSKI following RAI treatment be beneficial in certain patients with GD.

Cervical Tumor in Patient on Chronic Hemodialysis about a Case

Patients with Chronic Kidney Disease on Dialysis (CDRD) have a major risk of developing cancer when compared with the general population [1], thyroid carcinoma being the most common in the first group of patients [2]. The definitive treatment is thyroidectomy, but in patients at risk of recurrence ablative therapy with radioactive iodine I-131 is necessary [2]. We present the clinical case of a 61-year-old patient on hemodialysis with a slow growing anterior cervical tumor studied for more than two years until the diagnosis of papillary thyroid carcinoma. Initially the patient received surgical treatment and is currently awaiting treatment with radioactive iodine I-131.

I-131 myth bursting: association of pregnancy/infertility related adverse effects of radioactive iodine I-131 administration

Background: There is very little knowledge on the risks of genetically transmissible diseases after the exposure to radiation. This study aimed to investigate the influence of radioiodine [radioactive iodine therapy (RAI)] on the outcome of pregnancies and the health status of children born to mothers who had received therapeutic doses of I-131 for differentiated thyroid carcinoma or for hyperthyroidism. Methods: Gestational histories of 300 women who were treated with radioactive iodine either for the treatment of hyperthyroidism or for the treatment of thyroid cancer from 2012 to 2017 were retrospectively analyzed. Two Groups were made on the basis of administered doses of radioactive iodine. The first group was further divided into two sub groups. Sub group A consisted of the patients who were treated with radioactive iodine for hyperthyroidism with less than 30 mCi. Sub group B had patients of differentiated thyroid cancer that had been treated with doses above 100 mCi of I-131. Group 2 had patients with primary hypothyroidism and was on thyroxine replacement therapy. Control group consists of healthy young women with no comorbid delivered babies in this time interval. Results: The outcome of the 200 patients were as follows: 97 live births in the group A and 10 miscarriages, while in high dose group, 85 live births and 8 miscarriages were recorded versus 44 live births and 6 miscarriages in the group who were primary hypothyroid. In the control group, there were 50 patients who had 3 miscarriage and 47 healthy babies. Conclusion: Therefore, the present study concluded that radioactive iodine administration does not increased a women risk of infertility or early pregnancy failure.

Measurement of saturation overshoot under grass cover

The paper deals with non-destructive measurement of water infiltration into homogenous soil (Haplic Chernozem) covered by grass. The experimental site was located in Most pri Bratislave (Slovakia) in the Pannonian Basin at a height of 130 m above sea level. Radioactive tracer technique was used to determine the water content of the soil profile during water infiltration. A mixture of the radioactive iodine 131I (chemical form Na131I) and the NaI solution was used as a tracer. The tracer distribution in the soil was measured by the Geiger-Muller detector connected to the nuclear analyser. Gravity-driven fingers were detected in the soil under the grass cover as a consequence of the wetting front instability. The instability manifested itself as a non-monotonic moisture profile caused by saturation overshoot and a varying discharge from the soil profile in time.

Effect of the Exposure to Radioactive Iodine I-131 on Lymphocyte and Granulocyte Levels in Blood Samples of Hospital Workers

Effect of the Exposure to Radioactive Iodine I-131 on Lymphocyte and Granulocyte Levels in Blood Samples of Hospital Workers

SAT-605 Immune Thrombocytopenic Purpura in Graves' disease

Background: Immune thrombocytopenic purpura (ITP) in association with autoimmune thyroid diseases is a well-known entity. We report a case of Graves’ disease patient with coexisting ITP, where the control of ITP is in close relationship to control with Graves’ disease. Case Presentation: A 17-year-old female presented in 10/2014 with hyperthyroid symptoms for 4-5 months. Thyroid function tests (TFT’s) showed TSH 0.011 (0.45-4.5 mcIU/ml) and Total T4 (TT4) - 34.3 (4.5-12 ug/dl). Thyroid ultrasound showed thyromegaly without any discrete nodules. Thyroid uptake scan showed a homogeneous increased radiotracer uptake of 65% at 24 hours consistent with Graves’ disease and she was started on Methimazole (MMI) 20 mg PO daily. Over time, her hyperthyroidism remained well controlled on MMI 5 mg q other day, hence it was discontinued in 5/2016. She presented with multiple skin bruises in 12/2016 and her platelet count was noted to be 19 (150-400x103/ml). TFT’s remained normal. Her presumptive diagnosis was ITP given another autoimmune condition - Graves’ disease and was started on Prednisone 80 mg daily. She followed with hematology and her platelet count was monitored regularly and prednisone dose was adjusted. In 7/2017 her platelet count dropped to 64 on prednisone 5 mg PO daily. Repeat TFT’s showed TSH 0.01 and free T4 3.31. MMI was resumed at 20 mg PO daily. Labs three months later show TSH 0.024, free T4 0.86, TT3 102 and platelets 186. Given the recurrence of Graves’ disease she underwent radioactive iodine (RAI) I131 therapy in 1/2018. Post RAI she required levothyroxine 50 mcg daily briefly. In 5/2018 her platelet count dropped again to 59 on prednisone. TFT’s showed TSH of 0.014, free T4 1.42 and TT3 117. Graves’ disease relapsed despite RAI therapy and MMI was started at 5 mg PO daily. Her thyroid function remains well controlled on MMI 5 mg PO daily. Her platelet count also returned to normal and remains stable on Prednisone 5 mg PO daily. Discussion: There are several case reports of Graves’ disease and ITP in the literature. Several mechanisms by which thrombocytopenia occurs have been postulated. Accelerated platelet turnover by an activated reticuloendothelial system, shortened platelet survival and consequently reduced platelet counts can occur in patients with hyperthyroidism. Platelet survival return to normal in patients maintained in euthyroid state for more than six months. Genetic predisposition to both Graves’ disease and ITP appears to be related to HLA B8 and DR3 haplotypes. In our patient, each time she had a low platelet count on prednisone therapy, thyroid function tests were suggestive of relapse of Graves’ disease. Treatment of Graves’ disease has resulted in improved response of ITP to glucocorticoid therapy and normalization of platelet count. In patients with ITP on glucocorticoid therapy, unexplained drop in platelet count should prompt checking for thyroid function abnormalities.

Differentiated thyroid cancer theranostics: radioiodine and beyond.

The term theranostics is the combination of a diagnostic tool that helps to define the right therapeutic tool for specific disease. It signifies the "we know which sites require treatment (diagnostic scan) and confirm that those sites have been treated (post-therapy scan)" demonstrating the achievable tumor dose concept. This term was first used by John Funkhouser at the beginning of the 90s, at the same time the concept of personalized medicine appeared. In nuclear medicine, theranostics is easy to apply and understand because of an easy switch from diagnosis to therapy with the same vector. It helps in maximizing tumor dose and sparing normal tissue with high specific and rapid uptake in metastasis. The oldest application of this concept is radioactive iodine I-131 (RAI). The first treatment based on the theranostic concept was performed on thyroid cancer patients with RAI in 1946. From then on management of differentiated thyroid cancer (DTC) has evolved on the multimodality concept. We now use the term "our" patient instead of "my" patient to signify this. However, the initial surgical management followed by RAI as per the theranostics has remained the mainstay in achieving a cure in most of DTC patients. The normal thyroid cells metabolise iodine, the principle of which is utilized in imaging of the thyroid gland with isotopes of iodine. RAI treatment of DTC is based on the principle of sodium iodide symporter (NIS) expressing thyroid cells with DTC cells having the ability of trapping circulating RAI successfully helping in treatment of residual and metastatic disease. NIS is usually negative in poorly differentiated cells and is inversely proportional to Glucose transporter receptor Type 1 expression. Both positive and negative NIS are the key components of the theranostic approach in treatment of DTC. Presence or absence of NIS is documented by either whole body iodine scintigraphy (WBS) or 2-deoxy-2(18F) fludeoxyglucose (FDG) positron emission tomography computed tomography (PET-CT). Currently, single photon emission CT and CT (SPECT-CT) has significantly improved the precision and sensitivity of whole body iodine scintigraphy with its capability of accurate localization of disease foci whether iodine avid or non-avid. This has helped in a more personalized approach in treatment. This review will give an overview of the role of NIS in the theranostic approach to management with RAI, its current status and also the molecular approach to treatment in RAI refractory disease.

Comparative Histopathologic Analysis of "Radiogenic" and "Sporadic" Papillary Thyroid Carcinoma: Patients Born Before and After the Chernobyl Accident.

The issue of whether radiation-induced thyroid cancer is pathologically different from sporadic remains not fully answered. This study compared structural characteristics and invasive features of papillary thyroid carcinoma (PTC) in two age-matched groups: patients who were children (≤4 years old) at the time of the Chernobyl accident and who lived in three regions of Ukraine most contaminated by radioactive iodine 131I ("radiogenic" cancer), and those who lived in the same regions but who were born after 1987 and were not exposed to 131I ("sporadic" cancer). Further, the histopathologic features of PTC were analyzed in relation to age and individual 131I thyroid dose. The study included 301 radiogenic and 194 sporadic PTCs. According to age at surgery, patients were subdivided into children (≤14 years old), adolescents (15-18 years old), and adults (19-28 years old). Statistical analyses included univariate tests and multivariable logistic regression within and across the age subgroups. Analyses of morphological features related to 131I doses were conducted among exposed patients on categorical and continuous scales controlling for sex and age. Among children, radiogenic PTC displayed a significantly higher frequency of tumors with a dominant solid growth pattern, intrathyroidal spread, extrathyroidal extension, lymphatic/vascular invasion, and distant metastases. Exposed adolescents more frequently displayed extrathyroidal extension, lymphatic/vascular invasion, and distant metastases. Exposed adults more frequently had intrathyroidal spread and extrathyroidal extension. The frequency of PTC with dominant papillary pattern and oxyphilic cell metaplasia was significantly lower in radiogenic compared to sporadic tumors for all age groups. Manifestations of tumor aggressiveness were most frequent in children compared to adolescents and adults regardless of etiology. Radiogenic PTC is less likely to demonstrate a dominant papillary growth pattern and more likely to display more aggressive tumor behavior than sporadic PTC. Histopathologic tumor aggressiveness declines with patient age in both radiogenic and sporadic cases.

Risk stratification of 282 differentiated thyroid cancers found incidentally in 1369 total thyroidectomies according to the 2015 ATA guidelines; implications for management and treatment.

Introduction The purpose of this study was to evaluate the incidence of incidental differentiated thyroid carcinoma in thyroid operations for a benign preoperative diagnosis, to identify the risk factors involved and to risk stratify the cancer patients according to the 2015 American Thyroid Association (ATA) guidelines. Materials and methods The study was a retrospective review of all thyroidectomy operations performed in a single institution (January 2004 to January 2009). We excluded patients with a preoperative diagnosis of thyroid malignancy. Results Incidental differentiated thyroid carcinoma was diagnosed in 282/1369 patients (21%). The incidental group had a significantly higher number of males (19% vs 14%, P = 0.033) and a higher number of patients with histopathological evidence of thyroiditis (35% vs 25%, P = 0.004). There was a higher number of lymph nodes present in the incidental group but numbers did not reach statistical significance (17% vs 13%, P = 0.079). There were 270 cases in the ATA low-risk group (96%) and 12 cases in the ATA intermediate-risk group (4%). Patients with an ATA intermediate risk had a statistically higher number of capsule invasion, extrathyroidal extension and angioinvasion (P < 0.001, P < 0.001 and P < 0.001, respectively). Overall, 22% of patients with an incidental differentiated thyroid carcinoma should be considered for radioactive iodine 131I treatment. 29 of the 191 patients in American Joint Committee on Cancer stage I should be considered for radioactive iodine treatment (15%). Conclusions Males and patients with thyroiditis are at a higher risk for an incidental differentiated thyroid carcinoma. One of every five of patients diagnosed with cancer will need radioactive iodine treatment, even some patients with stage I disease.

A Review of TENIS Syndrome in Hospital Pulau Pinang.

Introduction:The treatment for differentiated thyroid cancers (DTCs) has always been radioactive iodine 131I therapy after definitive surgical management. Clinicians are faced with therapeutic challenges when dealing with patients having thyroglobulin-elevated negative iodine scintigraphy (TENIS) syndrome (elevated serum thyroglobulin [Tg] levels but negative whole-body scans [WBSs]).Objective:The aim of the study was to determine the prevalence of TENIS syndrome in our local setting and to evaluate the use of 18-fluoro-2-deoxyglucose (18F-FDG) positron emission tomography-computed tomography (PET-CT) in the management.Methodology:The data from DTC patients treated in the Department of Nuclear Medicine, Hospital Pulau Pinang from December 1, 2010, to November 30, 2016, with negative WBS and elevated Tg were reviewed. These patients should have undergone 18F-FDG PET-CT to be included in the study.Results:Only forty (10.4%) out of a total of 386 patients treated in Hospital Pulau Pinang during the study fulfilled the inclusion criteria. There were 28 women (70%) with median age of 59 years old. Thirty-four patients (85%) had papillary thyroid cancer (PTC) and six patients had follicular thyroid cancer. The use of 18F-FDG PET-CT revealed 23 patients (57.5%) with 18F-FDG avid metastases suggesting dedifferentiation of thyroid cancers. Based on this study, the probability of detecting FDG-avid disease is higher (P = 0.03) if 18F-FDG PET-CT was performed when Tg ≥15 ng/mL.Conclusion:TENIS syndrome constitutes a significant number of cases in our setting. Our data suggest a cutoff Tg ≥15 ng/mL for performing 18F-FDG PET-CT for these patients would be more beneficial than the currently American Thyroid Association recommended cutoff of 10 ng/mL.

Patients' instuction list for radioactive iodine I-131 treatment (for hyperthyroidism management)

This patient information guide sets out instructions for patients who plan to undergo radioactive iodine ablation for the management of uncontrolled hyperthyroidism. This information, shared in a reader-friendly format, will benefit both patients and health-care providers.