Korean Thyroid Association Guidelines on the Management of Differentiated Thyroid Cancers; Part I. Initial Management of Differentiated Thyroid Cancers - Chapter 6. Radioactive Iodine Treatment after Thyroidectomy 2024

The initial treatment for differentiated thyroid cancer includes appropriate surgery and radioactive iodine (RAI) therapy, followed by thyroid-stimulating hormone (TSH) suppression therapy as long-term management to prevent recurrence. RAI therapy following thyroidectomy has the three main purposes: remnant ablation, adjuvant therapy, and therapy for known disease. To optimize the goals and targets of RAI therapy, postoperative disease assessment, determination of recurrence risk, and consideration of various individual factors are necessary. The objectives of RAI therapy are determined based on the individual’s recurrence risk, and the administered activity of RAI is then determined according to these treatment objectives. Adequate stimulation of serum TSH is necessary before RAI therapy, and recombinant human TSH is widely used because of its advantage in reducing the risk of exacerbation of comorbidities associated with levothyroxine discontinuation and improving patients’ quality of life. Additionally, reducing iodine intake through appropriate low-iodine diet is necessary. Whole-body scans are conducted to assess the disease status after RAI therapy. If planar whole-body scans are inconclusive, additional single-photon emission computed tomography (SPECT)/CT imaging is recommended. Over the past decade, prospective randomized or retrospective clinical studies on the selection of candidates for RAI therapy, administered activity, methods of TSH stimulation, and advantages of SPECT/CT have been published. Based on these latest clinical research findings and recommendations from relevant overseas medical societies, this clinical practice guideline presents the indications and methods for administering RAI therapy after thyroidectomy.

Korean Thyroid Association Guidelines on the Management of Differentiated Thyroid Cancers; Part II. Follow-up Surveillance after Initial Treatment 2024

Based on the clinical, histopathological, and perioperative data of a patient with differentiated thyroid cancer (DTC), risk stratification based on their initial recurrence risk is a crucial follow-up (FU) strategy during the first 1–2 years after initial therapy. However, restratifiying the recurrence risk on the basis of current clinical data that becomes available after considering the response to treatment (ongoing risk stratification, ORS) provides a more accurate prediction of the status at the final FU and a more tailored management approach. Since the 2015 American Thyroid Association Management Guidelines for Adult Patients with Thyroid Nodules and DTC, the latest guidelines that include the National Comprehensive Cancer Network clinical practice and European Association for Medical Oncology guidelines have been updated to reflect several recent evidence in ORS and thyroid-stimulating hormone (TSH) suppression of DTC. The current clinical practice guideline was developed by extracting FU surveillance after the initial treatment section from the previous version of guidelines and updating it to reflect recent evidence. The current revised guideline includes recommendations for recent ORS, TSH target level based on risk stratification, FU tools for detection of recurrence and assessment of disease status, and long-term FU strategy for consideration of the disease status. These evidence-based recommendations are expected to avoid overtreatment and intensive FU of the majority of patients who will have a very good prognosis after the initial treatment of DTC patients, thereby ensuring that patients receive the most appropriate and effective treatment and FU options.

Korean Thyroid Association Guidelines on the Management of Differentiated Thyroid Cancers; Part III. Management of Advanced Differentiated Thyroid Cancers - Chapter 3.Radioactive Iodine Therapy in Advanced Thyroid Cancer 2024

Radioactive iodine (RAI) therapy can effectively eliminate persistent or recurrent disease in patients with advanced differentiated thyroid cancer (DTC), potentially improving progression-free, disease-specific, and overall survival rates. Repeated administration of RAI along with thyroid-stimulating hormone (TSH) suppression is the mainstay of treatment for patients with distant metastases. Remarkably, one in three patients with distant metastases can be cured using RAI therapy and experience a near-normal life expectancy. Patients with elevated serum thyroglobulin and a negative post-RAI scan may be considered for empiric RAI therapy in the absence of structurally evident disease. However, in some patients, the iodine uptake capacity of advanced lesions decreases over time, potentially resulting in RAI-refractory disease. RAI-administered dose can be either empirically fixed high activities or dosimetry-based individualized activities for treatment of known diseases. The preparation method (levothyroxine withdrawal vs. recombinant human TSH administration) should be individualized for each patient.RAI therapy is a reasonable and safe treatment for patients with advanced DTC. Despite the risk of radiation exposure, administration of low-activity RAI has not been associated with an increased risk of a secondary primary cancer (SPM), leukemia, infertility, adverse pregnancy outcomes, etc. However, depending on the cumulative dose, there is a risk of acute or delayed-onset adverse effects including salivary gland damage, dental caries, nasolacrimal duct obstruction, and SPM. Therefore, as with any treatment, the expected benefit must justify the use of RAI in patients with advanced DTC.

Korean Thyroid Association Management Guidelines for Patients with Thyroid Nodules 2024

Thyroid nodules represent a prevalent condition that is detectable via palpation or ultrasound. In recent years, there has been a paradigm shift toward enhanced diagnostic precision and less aggressive therapeutic approaches, highlighting the growing necessity for tailored clinical recommendations to optimize patient outcomes. The Korean Thyroid Association (KTA) has developed guidelines for managing patients with thyroid nodules, following a comprehensive review by task force members of the relevant literature identified via electronic database searches. The recommendations are provided with a level of recommendation for each section. The guidelines encompass thyroid cancer screening in high-risk groups, appropriate diagnostic methods for thyroid nodules, role of pathologic and molecular marker testing in making a diagnosis, long-term follow-up and treatment of benign thyroid nodules, and special considerations for pregnant women. The major revisions that were made in the 2023 guidelines were the definition of high-risk groups for thyroid cancer screening, application of the revised Korean Thyroid Imaging Reporting and Data System (K-TIRADS), addition of the role of core needle biopsy and molecular marker tests, application of active surveillance in patients with low-risk papillary thyroid microcarcinoma, and updated indications for nonsurgical treatment of benign thyroid nodules. In the 2024 revision of the KTA guidelines for thyroid cancer, the evidence for some recommendations has been updated to address the tumor size in the context of active surveillance in patients with low-risk thyroid cancer and the surgical size cutoff. These evidence-based recommendations serve to inform clinical decision-making in the management of thyroid nodules, thereby facilitating the delivery of optimal and efficacious treatments to patients.

Korean Thyroid Association Guidelines on the Management of Differentiated Thyroid Cancers; Part V. Pediatric Differentiated Thyroid Cancer 2024

Pediatric differentiated thyroid cancers (DTCs), mostly papillary thyroid cancer (PTC, 80-90%), are diagnosed at more advanced stages with larger tumor sizes and higher rates of locoregional and/or lung metastasis. Despite the higher recurrence rates of pediatric cancers than of adult thyroid cancers, pediatric patients demonstrate a lower mortality rate and more favorable prognosis. Considering the more advanced stage at diagnosis in pediatric patients, preoperative evaluation is crucial to determine the extent of surgery required. Furthermore, if hereditary tumor syndrome is suspected, genetic testing is required. Recommendations for pediatric DTCs focus on the surgical principles, radioiodine therapy according to the postoperative risk level, treatment and follow-up of recurrent or persistent diseases, and treatment of patients with radioiodine-refractory PTCs on the basis of genetic drivers that are unique to pediatric patients.

Korean Thyroid Association Guidelines on the Management of Differentiated Thyroid Cancers; Overview and Summary 2024

Differentiated thyroid cancer demonstrates a wide range of clinical presentations, from very indolent cases to those with an aggressive prognosis. Therefore, diagnosing and treating each cancer appropriately based on its risk status is important. The Korean Thyroid Association (KTA) has provided and amended the clinical guidelines for thyroid cancer management since 2007. The main changes in this revised 2024 guideline include 1) individualization of surgical extent according to pathological tests and clinical findings, 2) application of active surveillance in low-risk papillary thyroid microcarcinoma, 3) indications for minimally invasive surgery, 4) adoption of World Health Organization pathological diagnostic criteria and definition of terminology in Korean, 5) update on literature evidence of recurrence risk for initial risk stratification, 6) addition of the role of molecular testing, 7) addition of definition of initial risk stratification and targeting thyroid stimulating hormone (TSH) concentrations according to ongoing risk stratification (ORS), 8) addition of treatment of perioperative hypoparathyroidism, 9) update on systemic chemotherapy, and 10) addition of treatment for pediatric patients with thyroid cancer.

2023 Korean Thyroid Association Management Guidelines for Patients with Thyroid Nodules

Thyroid nodules are a prevalent condition that can be detected through palpation or ultrasound. However, a small fraction of these nodules can be cancerous, and even benign nodules can cause symptoms if they grow and compress surrounding tissue. As such, it is important to monitor thyroid nodules and determine appropriate treatment options. In recent years, there has been a shift towards enhancing diagnostic accuracy and less aggressive treatment options. As a result, there is a growing need for the development of appropriate recommendations for their clinical application to ensure optimal patient outcomes. The present clinical practice guideline was developed by extracting the nodule section from the prior version of guidelines and updating it to fit the Korean circumstances. Task force members reviewed relevant studies selected after electronic database searching, and the recommendations are provided with a level of recommendation for each section. The revised guideline includes recommendations for thyroid cancer screening in high-risk groups, appropriate diagnostic methods for thyroid nodules, the role of pathological and molecular marker tests in diagnosis, long-term follow-up and treatment of benign thyroid nodules, and special considerations for pregnant women. The major changes in this revision are the definition of high-risk groups for thyroid cancer screening, the application of the revised Korean Thyroid Imaging Reporting and Data System (K-TIRADS), the addition of the role of core needle biopsy and molecular marker tests, the application of active surveillance in low-risk papillary thyroid microcarcinoma, and updated indications for non-surgical treatment of benign thyroid nodules. These evidence-based recommendations are expected to assist in clinical decision-making for thyroid nodule management, ensuring that patients receive the most appropriate and effective treatment options.

Current Status of PSMA‑Targeted Radioligand Therapy in the Era of Radiopharmaceutical Therapy Acquiring Marketing Authorization / 대한핵의학회잡지

Prostate-specific membrane antigen (PSMA) is highly expressed in PCa, which gradually increases in high-grade tumors, metastatic tumors, and tumors nonresponsive to androgen deprivation therapy. PSMA has been a topic of interest during the past decade for both diagnostic and therapeutic targets. Radioligand therapy (RLT) utilizes the delivery of radioactive nuclides to tumors and tumor-associated targets, and it has shown better efficacy with minimal toxicity compared to other systemic cancer therapies. Nuclear medicine has faced a new turning point claiming theranosis as the core of academic identity, since new RLTs have been introduced to clinics through the official new drug development processes for approval from the Food and Drug Administration (FDA) or European Medical Agency. Recently, PSMA targeting RLT was approved by the US FDA in March 2022. This review introduces PSMA RLT focusing on ongoing clinical trials to enhance our understanding of nuclear medicine theranosis and strive for the development of new radiopharmaceuticals.

Prognostic influence of Korean public medical insurance system on breast cancer patients

PURPOSE: To investigate the prognostic influence of Korean public medical insurance system on breast cancer patients. METHODS: Data of 1,068 patients with primary invasive breast cancer were analyzed. Korean public medical insurance status was classified into 2 groups: National Health Insurance and Medical Aid. Kaplan-Meier estimator and Cox proportional hazards model were used for survival analysis. RESULTS: The Medical Aid group showed worse prognoses compared to the National Health Insurance group both in overall survival (P = 0.001) and recurrence-free survival (P = 0.006). The Medical Aid group showed higher proportion of patients with tumor size > 2 cm (P = 0.022), more advanced stage (P = 0.039), age > 50 years (P = 0.003), and low education level (P = 0.003). The Medical Aid group showed higher proportion of patients who received mastectomy (P < 0.001) and those who received no radiation therapy (P = 0.013). The Medical Aid group showed a higher rate of distant recurrence (P = 0.014) and worse prognosis for the triple negative subtype (P = 0.006). Medical insurance status was a significant independent prognostic factor in both univariate analysis and multivariate analysis. CONCLUSION: The Medical Aid group had worse prognosis compared to the National Health Insurance group. Medical insurance status was a strong independent prognostic factor in breast cancer. Unfavorable clinicopathologic features could explain the worse prognosis for the Medical Aid group. Careful consideration should be given to medical insurance status as one of important prognostic factors for breast cancer patients.

Findings of Single-Photon Emission Computed Tomography and Its Relation with Quantitative Coronary Angiography in Patients with Significant Stenosis of the Left Main Coronary Artery

OBJECTIVE: Unrecognized left main coronary artery disease (LMCD) is often fatal; however, accuracy of non-invasive tests for diagnosing LMCD is still unsatisfactory. This study was performed to elucidate single-photon emission computed tomography (SPECT) detection of LMCD using quantitative coronary angiography (QCA) data. MATERIALS AND METHODS: Fifty-five patients (39 men; mean age, 68.1 ± 10.9 years) diagnosed with significant left main (LM) stenosis (≥ 50%) by invasive coronary angiography (ICA) were retrospectively reviewed. All study patients underwent SPECT with pharmacologic stress within 30 days of ICA. All coronary lesions were quantified via QCA, and SPECT findings were compared with QCA results. RESULTS: Only four patients (7.3%) had isolated LMCD; all others had combined significant stenosis (≥ 70%) of one or more other epicardial coronary arteries. Patients with more severe coronary artery disease tended to have higher values for summed difference scores in a greater number of regions, but the specific pattern was not clearly defined. Summed stress score of SPECT did not differ according to LM stenosis severity. Only three patients (5.4%) had a typical LM pattern of reversible perfusion defect on SPECT. A significant negative linear correlation between stenosis severity and stress perfusion percent was found in the left anterior descending artery region (r = −0.455, p < 0.001) but not in the left circumflex artery. CONCLUSION: Single-photon emission computed tomography findings were heterogeneous, not specific and poorly correlated to QCA data in patients with significant LMCD. This may be due to highly prevalent significant stenosis of other epicardial coronary arteries.

Prostate-Specific Membrane Antigen PET Imaging in Prostate Cancer: Opportunities and Challenges

The aim of this systematic review was to describe the characteristics of prostate-specific membrane antigen (PSMA)-targeting PET and their clinical applications in prostate cancer patients. There have been major strides in the design, synthesis of PSMA-targeting PET tracers over the past several years. PSMA-targeting PET tracers can be categorized, according to positron emitters and targeting strategies for the PSMA. The majority of PSMA PET studies has been focused on patients with biochemical recurrence, but additional values of PSMA PET have also been investigated for use in primary staging, treatment planning, response evaluation, and PSMA radioligand therapy. PSMA PET is expected to bring improvements in the management of patients, but the impact of improved diagnosis by PSMA on overall survival remains unanswered. Many challenges still await PSMA PET to expedite the use in the clinical practice. At this early stage, prospective multicenter trials are needed to validate the effectiveness and usefulness of PSMA PET.

Incidentally Detected Small Intestine Intussusception Caused by Primary Small Intestine Carcinoma on ¹⁸F-FDG PET/CT / 대한핵의학회잡지

Small intestine intussusception in adults is a rare condition mainly caused by primary or metastatic small intestine malignancy. Here, we present a 72-year-old male patient who was diagnosed with small intestine cancer that was presented as small intestine intussusception on hybrid 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT). The patient was initially referred for an abnormality on a chest radiography and severe anemia. FDG PET/CT showed the lung lesion in the right upper lobe of lung as a high FDG uptake mass. Accidentally, FDG PET demonstrated another intense hypermetabolic intraluminal lesion in the small intestine accompanied with intussusception shown as a circumferential hypermetabolic wall. By pathologic examination, the patient was diagnosed as primary small intestine cancer with lung metastasis. This case highlights usefulness of hybrid FDG PET/CT to identify unexpected malignancy.

Influence of Androgen Deprivation Therapy on the Uptake of PSMA-Targeted Agents: Emerging Opportunities and Challenges / 대한핵의학회잡지

Prostate-specific membrane antigen (PSMA) is an attractive target for both diagnosis and therapy because of its high expression in the vast majority of prostate cancers. Development of small molecules for targeting PSMA is important for molecular imaging and radionuclide therapy of prostate cancer. Recent evidence implies that androgendeprivation therapy increase PSMA-ligand uptake in some cases. The reported upregulations in PSMA-ligand uptake after exposure to second-generation antiandrogens such as enzalutamide and abiraterone might disturb PSMA-targeted imaging for staging and response monitoring of patients undergoing treatment with antiandrogen-based drugs. On the other hand, second-generation antiandrogens are emerging as potential endoradio-/chemosensitizers. Therefore, the enhancement of the therapeutic efficiency of PSMA-targeted theranostic methods can be listed as a new capability of antiandrogens. In this manuscript, we will present what is currently known about the mechanism of increasing PSMA uptake following exposure to antiandrogens. In addition, we will discuss whether these above-mentioned antiandrogens could play the role of endoradio-/chemosensitizers in combination with the well-established PSMA-targeted methods for pre-targeting of prostate cancer.

New Strategies for Combined Radioiodine Therapy in Refractory Thyroid Cancer / 대한갑상선학회지

The prognosis of differentiated thyroid cancer (DTC) is excellent, which is mainly due to the high therapeutic efficacy of radioactive iodine (RAI) therapy as well as indolent nature of thyroid cancer itself. Although most patients with DTC are well treated with RAI therapy, a certain number of patients have been suffered from refractoriness to RAI therapy. To overcome refractoriness, many alternative treatments have been investigated, and they could be classified based on the mechanisms of action; redifferentiation drug and molecular targeted drug. Not only redifferentiated drugs but also molecular targeted drugs could induce differentiation of thyroid cancer cells. Consequently, alternative treatments allowing tumor cells of RAI avidity followed by RAI therapy could utilize a synergistic effect of both therapies. Combined RAI therapy is expected to improve therapeutic effects and prognoses of RAI refractory thyroid cancers.

Clinical Outcome of Remnant Thyroid Ablation with Low Dose Radioiodine in Korean Patients with Low to Intermediate-risk Thyroid Cancer

Radioiodine activity required for remnant thyroid ablation is of great concern, to avoid unnecessary exposure to radiation and minimize adverse effects. We investigated clinical outcomes of remnant thyroid ablation with a low radioiodine activity in Korean patients with low to intermediate-risk thyroid cancer. For remnant thyroid ablation, 176 patients received radioiodine of 1.1 GBq, under a standard thyroid hormone withdrawal and a low iodine diet protocol. Serum levels of thyroid stimulating hormone stimulated thyroglobulin (off-Tg) and thyroglobulin-antibody (Tg-Ab), and a post-therapy whole body scan (RxWBS) were evaluated. Completion of remnant ablation was considered when there was no visible uptake on RxWBS and undetectable off-Tg (<1.0 ng/mL). Various factors including age, off-Tg, and histopathology were analyzed to predict ablation success rates. Of 176 patients, 68.8% (n = 121) who achieved successful remnant ablation were classified into Group A, and the remaining 55 were classified into Group B. Group A presented with significantly lower off-Tg at the first radioiodine administration (pre-ablative Tg) than those of Group B (1.2 +/- 2.3 ng/mL vs. 6.2 +/- 15.2 ng/mL, P = 0.027). Pre-ablative Tg was the only significant factor related with ablation success rates. Diagnostic performances of pre-ablative Tg < 10.0 ng/mL were sensitivity of 99.1%, specificity of 14.0%, positive predictive value of 71.1%, and negative predictive value of 87.5%, respectively. Single administration of low radioiodine activity could be sufficient for remnant thyroid ablation in patients with low to intermediate-risk thyroid cancer. Pre-ablative Tg with cutoff value of 10.0 ng/mL is a promising factor to predict successful remnant ablation.

Prediction of response by FDG PET early during concurrent chemoradiotherapy for locally advanced non-small cell lung cancer

PURPOSE: To evaluate the predictive value of the early response of 18F-flurodeoxyglucose positron emission tomography (FDG PET) during concurrent chemoradiotherapy (CCRT) for locally advanced non-small cell lung cancer (NSCLC). MATERIALS AND METHODS: FDG PET was performed before and during CCRT for 13 NSCLC patients. Maximum standardized uptake value (SUVmax), mean standardized uptake value (SUVmean), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were measured and the changes were calculated. These early metabolic changes were compared with the standard tumor response by computed tomograms (CT) one month after CCRT. RESULTS: One month after the completion of CCRT, 9 patients had partial response (PR) of tumor and 4 patients had stable disease. The percent changes of SUVmax (%DeltaSUVmax) were larger in responder group than in non-responder group (55.7% +/- 15.6% vs. 23.1% +/- 19.0%, p = 0.01). The percent changes of SUVmean (%DeltaSUVmean) were also larger in responder group than in non-responder group (54.4% +/- 15.9% vs. 22.3% +/- 23.0%, p = 0.01). The percent changes of MTV (%DeltaMTV) or TLG (%DeltaTLG) had no correlation with the tumor response after treatment. All the 7 patients (100%) with %DeltaSUVmax > or = 50% had PR, but only 2 out of 6 patients (33%) with %DeltaSUVmax or = 50% had PR, but only 3 out of 7 patients (43%) with %DeltaSUVmean < 50% had PR after CCRT (p = 0.026). CONCLUSION: The degree of metabolic changes measured by PET-CT during CCRT was predictive for NSCLC tumor response after CCRT.

Pulmonary Artery Embolotherapy in a Patient with Type I Hepatopulmonary Syndrome after Liver Transplantation

Although liver transplantation (LT) is the only effective treatment option for hepatopulmonary syndrome (HPS), the post-LT morbidity and mortality have been high for patients with severe HPS. We performed post-LT embolotherapy in a 10-year-old boy who had severe type I HPS preoperatively, but he failed to recover early from his hypoxemic symptoms after an LT. Multiple embolizations were then successfully performed on the major branches that formed the abnormal vascular structures. After the embolotherapy, the patient had symptomatic improvement and he was discharged without complications.

Camurati-Engelmann's Disease on (99m)Tc-MDP Bone Scan / 핵의학분자영상

A 24 year-old female presented for a (99m)Tc-methylene diphosphonatae (MDP) whole body bone scan due to chronic pain in the bilateral lower extremities that has aggravated since 2002. She was diagnosed with Camurati-Engelmann disease (CED) based on the clinical and radiological findings in 2002, and she re-visited our institute to evaluate disease status at this time. CED is a rare autosomal dominant type of bone dysplasia characterized by progressive cortical thickening of long bones, and narrowing of medullary cavity, and thus presents with typical clinical symptoms and signs such as chronic pain in the extremities, muscle weakness, and waddling gait. On the (99m)Tc-MDP bone scan performed to evaluate disease status, intense increased uptake was seen in the skull, facial bones, bilateral scapulae, bilateral long bones, and bilateral pelvic bones, which clearly demonstrated the extent of CED involvement.

Evaluation of Multiple System Atrophy and Early Parkinson's Disease Using (123)I-FP-CIT SPECT / 핵의학분자영상

PURPOSE: We investigated quantification of dopaminergic transporter (DAT) and serotonergic transporter (SERT) on (123)I-FP-CIT SPECT for differentiating between multiple systemic atrophy (MSA) and idiopathic Parkinson's disease (IPD). MATERIALS AND METHODS: N-fluoropropyl-2beta-carbomethoxy-3beta-4-[(123)I]-iodophenylnortropane SPECT ((123)I-FP-CIT SPECT) was performed in 8 patients with MSA (mean age: 64.0+/-4.5yrs, m:f=6:2), 13 with early IPD (mean age: 65.5+/-5.3yrs, m:f=9:4), and 12 healthy controls (mean age: 63.3+/-5.7yrs, m:f=8:4). Standard regions of interests (ROIs) of striatum to evaluate DAT, and hypothalamus and midbrain for SERT were drawn on standard template images and applied to each image taken 4 hours after radiotracer injection. Striatal specific binding for DAT and hypothalamic and midbrain specific binding for SERT were calculated using region/reference ratio based on the transient equilibrium method. Group differences were tested using ANOVA with the postHoc analysis. RESULTS: DAT in the whole striatum and striatal subregions were significantly decreased in both patient groups with MSA and early IPD, compared with healthy control (p<0.05 in all). In early IPD, a significant increase in the uptake ratio in anterior and posterior putamen and a trend of increase in caudate to putamen ratio was observed. In MSA, the decrease of DAT was accompanied with no difference in the striatal uptake pattern compared with healthy controls. Regarding the brain regions where (123)I-FP-CIT binding was predominant by SERT, MSA patients showed a decrease in the binding of (123)I-FP-CIT in the pons compared with controls as well as early IPD patients (MSA: 0.22+/-0.1 healthy controls: 0.33+/-0.19, IPD: 0.29+/-0.19), however, it did not reach the statistical significance. CONCLUSION: In this study, the differential patterns in the reduction of DAT in the striatum and the reduction of pontine (123)I- FP-CIT binding predominant by SERT could be observed in MSA patients on (123)I- FP-CIT SPECT. We suggest that the quantification of SERT as well as DAT using (123)I- FP-CIT SPECT is helpful to differentiate parkinsonian disorders in early stage.

Diffuse Bone Marrow Uptake of 99mTc-MIBI in A Case of Intravascular Large B-cell Lymphoma / 핵의학분자영상

Intravascular large B-cell lymphoma (IVLBCL) is a subtype of diffuse large cell lymphoma, characterized by proliferation of lymphoid cells in the intravascular space of various organs without causing a mass effect. Although 18F-FDG PET is a powerful imaging tool in lymphoma, the usefulness of 18F-FDG PET in the assessment of IVLBCL is still controversial. 99mTc-MIBI, a tumor imaging radiopharmaceutical with a different mechanism from that of 18F-FDG, has been reported to be also effective in lymphoma. However, there is nearly no report on the efficacy of 99mTc-MIBI in the assessment of IVLBCL. We present one case of IVLBCL that showed 99mTc-MIBI accumulation in the involved bone marrow as an incidental finding, which was discrepant from that of 18F-FDG PET.