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PURPOSE OF REVIEW: Thyroid cancers are endocrine neoplasms with diverse gene expression and behavior, for which constantly evolving anatomic and functional imaging/theranostic agents have an essential role for diagnosis, staging, and treatment. RECENT FINDINGS: To achieve definitive diagnosis, neck ultrasound and associated risk stratification systems, notably Thyroid Imaging Reporting and Data System (TI-RADS), allow improved thyroid nodule characterization and management guidance. Radioactive iodine-131 (RAI) has long played a role in management of differentiated thyroid cancer (DTC), with recent literature emphasizing its effectiveness for intermediate-high risk cancers, exploring use of dosimetry for personalized medicine, and potential for retreatment with RAI following tumor redifferentiation. Iodine-124 positron emission tomography/computed tomography (PET/CT) has promising application for DTC staging and dosimetry. F18-fluorodeoxyglucose (FDG) PET/CT is used for staging of high risk DTC and identification of noniodine-avid disease recurrences, with metabolic uptake consistently portending poor prognosis. Poorly differentiated and anaplastic thyroid cancers are best assessed with anatomic imaging and F18-FDG PET/ CT, though recent studies show a potential theranostic role for Ga68/Lu177-prostate-specific membrane antigen. Medullary thyroid cancers are evaluated with ultrasound, CT, magnetic resonance imaging, and various positron-emitting radiotracers for PET imaging (F18-DOPA, F18-FDG, and recently Ga68-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA)–octreotate (DOTATATE)); the latter may enable treatment with Lu177-DOTATATE. SUMMARY: Multidisciplinary collaboration is essential to streamline appropriate management, given the wide array of available imaging and new therapies for metabolic and genetically complex cancers.

Our goal is to quantitatively compare radiotracer biodistributions within tumors and major normal organs on pretherapy 68 Ga-DOTATATE PET to post-therapy 177 Lu-DOTATATE single-photon emission computed tomography (SPECT) in patients receiving peptide receptor radionuclide therapy (PRRT).PET/CT at ~ 60 min postinjection of Ga-68 DOTATATE and research 177 Lu-SPECT/CT imaging ~ at 4 h (SPECT1) and ~ 24 h (SPECT2) post-cycle#1 were available. Manual contours of lesions on baseline CT or MRI were applied to co-registered SPECT/CT and PET/CT followed by deep learning-based CT auto-segmentation of organs. Tumor-to-normal organ ratios (TNR) were calculated from standardized uptake values (SUV) mean and SUV peak for tumor, and SUV mean for non-tumoral liver (nliver), spleen and kidney.There were 90 lesons in 24 patients with progressive metastatic neuroendocrine tumor. The correlation between PET and SPECT SUV TNRs were poor/moderate: PET versus SPECT1 R 2 = 0.19, 0.21, 0.29; PET versus SPECT2 R 2 = 0.06, 0.16, 0.33 for TNR nliver ,TNR spleen ,TNR kidney , respectively. Across all patients, the average value of the TNR measured on PET was significantly lower than on SPECT at both time points ( P 0.001). Using SUV mean for tumor, average TNR values and 95% confidence intervals (CI) were PET: TNR nliver = 3.5 [CI: 3.0-3.9], TNR spleen = 1.3 [CI, 1.2-1.5], TNR kidney = 1.7 [CI: 1.6-1.9]; SPECT1: TNR nliver = 10 [CI: 8.2-11.7], TNR spleen = 2.9 [CI: 2.5-3.4], TNR kidney = 2.8 [CI: 2.3-3.3]; SPECT2: TNR nliver = 16.9 [CI: 14-19.9], TNR spleen = 3.6 [CI: 3-4.2], TNR kidney = 3.6 [CI: 3.0-4.2]. Comparison of PET and SPECT results in a sphere phantom study demonstrated that these differences are not attributed to imaging modality.Differences in TNR exist for the theranostic pair, with significantly higher SUV TNR on 177 Lu SPECT compared with 68 Ga PET. We postulate this phenomenon is due to temporal differences in DOTATATE uptake and internalization in tumor as compared to normal organs.

Background The efficacy of exercise interventions in the treatment of mental health disorders is well known, but research is lacking on the most efficient exercise type for specific mental health disorders. Objective The present study aimed to compare and rank the effectiveness of various exercise types in the treatment of mental health disorders. Methods The PubMed, Web of Science, PsycINFO, SPORTDiscus, CINAHL databases, and the Cochrane Central Register of Controlled Trials as well as Google Scholar were searched up to December 2021. We performed pairwise and network meta-analyses as well as meta-regression analyses for mental health disorders in general and each type of mental health disorder, with alterations in symptom severity as the primary outcome. Results A total of 6456 participants from 117 randomized controlled trials were surveyed. The multimodal exercise (71%) had the highest probability of being the most efficient exercise for relieving depressive symptoms. While resistance exercise (60%) was more likely to be the most effective treatment for anxiety disorder, patients with post-traumatic stress disorder (PTSD) benefited more from mind–body exercise (52%). Furthermore, resistance exercise (31%) and multimodal exercise (37%) had more beneficial effects in the treatment of the positive and negative symptoms of schizophrenia, respectively. The length of intervention and exercise frequency independently moderated the effects of mind–body exercise on depressive (coefficient = 0.14, p = .03) and negative schizophrenia (coefficient = 0.96, p = .04) symptoms. Conclusion Multimodal exercise ranked best for treating depressive and negative schizophrenic symptoms, while resistance exercise seemed to be more beneficial for those with anxiety-related and positive schizophrenic symptoms. Mind–body exercise was recommended as the most promising exercise type in the treatment of PTSD. However, the findings should be treated with caution due to potential risk of bias in at least one dimension of assessment and low-to-moderate certainty of evidence. Trial Registration This systematic review was registered in the PROSPERO international prospective register of systematic reviews (CRD42022310237).

1118 Objectives: To better understand synovial sarcoma of the prostate. Background:Synovial sarcoma (SS) is a soft tissue sarcoma of uncertain histogenesis, chiefly occurring in young adults, primarily in the para-articular region of the extremities. Primary synovial sarcoma of the prostate is an uncommon malignant tumor. Case Report: We present a case of 42-year-old man with lower abdominal distension and discomfort, along with tenesmus. Transrectal ultrasound showed an 5.6 × 5.6 × 5.3cm lesion localized in the right peripheral band of prostate with heterogeneous mixed echogenicity. Magnetic resonance imaging (MRI) demonstrated a mass that appeared to originate in the right peripheral band of prostate. The right seminal vesicle gland and rectum was involved. His serum prostate-specific antigen was 0.58 ng/ml. Free prostate-specific antigen was 0.08ng/ml. 18F-fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) showed active metabolism of the soft tissue mass in the right peripheral zone of the prostate and the right seminal vesicle gland, with SUVmax of about 4.0. The lesion was not clearly decomposed with the posterior rectum. Transrectal puncture biopsy of prostate masses revealed synovial sarcoma of prostate. PET/CT after four cycles of Adriamycin and Icyclophosphamide showed that the tumor volume decreased and metabolism decreased significantly. Patient receive radical prostatectomy including bladder, prostate, seminal vesicle resection, and pelvic lymph node dissection.The final pathologic findings were consistent with the diagnosis of synovial sarcoma and right seminal vesicle gland involved. Radiotherapy and two cycles of adriamycin and Icyclophosphamide were given after surgery. PET/CT which is 4 months after surgery showed no signs of tumor recurrence or metastasis. Surprisingly, postoperative 16 months PET/CT did not show any other primary or metastatic focus. At two years of follow-up, the patient is survival very good up to now. Conclusions: In conclusion, we demonstrate a case of primary prostatic synovial sarcoma. Due to the paucity of cases of synovial sarcoma involving the prostate, the diagnose and treatment are not well defined. 18F-FDG PET/CT plays an important role in the diagnoses, staging, re-staging, evaluation of therapeutic effect and follow-up observation of primary prostate synovial sarcoma.

PURPOSE: To evaluate the effectiveness of propranolol at mitigating FDG uptake in brown adipose tissue (BAT) of pediatric patients with known or suspected malignancies. METHODS: PET/CT scans of 3 cohorts of patients treated from 2005–2017 were scored for presence of FDG uptake by BAT at 7 sites: right or left neck/supraclavicular area, right or left axilla, anterior mediastinum, posterior thorax, and abdomen/pelvis. Uptake was scored as follows: 0-none, 1-mild uptake < liver, 2-moderate uptake = liver, 3-intense uptake > liver. Group 1 consisted of 323 patients (630 scans) who had no specific preparation to mitigate FDG uptake by BAT. Group 2 consisted of 345 patients (705 scans) who underwent only warming in an uptake room with a fixed temperature at 24°C. Group 3 consisted of 622 patients (1457 scans) who underwent warming. In Group 3, patients 8 years and older, 471 patients (1114 scans), were also pre-medicated with oral propranolol 60 minutes before injection of FDG. Generalized estimation equation, using the logit link method, was used to model the relationship between the incidence of BAT score > 0, in any site, as a function of age, sex, seasonal effect, and body surface area (BSA). RESULTS: In patients aged 8 years or older, the incidence of BAT uptake was 35 – 44% and declined to 15% with propranolol. BAT was most frequent in the neck (26%), axilla (18%), posterior thorax (18%), mediastinum (14%), and abdomen/pelvis (8%); BAT was less common in warm months (p=0.001). No substantial benefit was shown with pre-injection warming alone. No significant effect was found for age, sex, or BSA separately. When BAT uptake was present, it was usually intense. CONCLUSION: Propranolol preparation minimizes FDG uptake by BAT and should be considered routine for pediatric FDG PET/CT cancer-related protocols in children, adolescents, and young adults.

Altered biodistribution of [F-18]2-fluoro-2-deoxyglucose (FDG) is sometimes encountered in pediatric patients undergoing chemotherapy for lymphoma on post-induction positron emission tomography (PET) imaging. A characteristic pattern of increased FDG uptake in white adipose tissue can be seen, particularly in the buccal regions, body wall and gluteal regions, with a shift of radiotracer away from the blood pool and liver. This altered biodistribution has been attributed to effects of corticosteroids in pediatric and adult patients and is important to recognize because of its potential for limiting the diagnostic quality of the PET scan and interfering with therapeutic response assessment. In contrast to the well-known metabolically active brown fat seen on up to one-third of pediatric PET scans, white fat is usually non-metabolically active. We sought to determine the incidence of altered distribution of FDG in subcutaneous white adipose tissue in pediatric patients undergoing PET imaging and to assess the association with corticosteroid use. We reviewed the medical records and imaging for four children in whom altered biodistribution in white adipose tissue was present on post-induction FDG PET/CT, identified during routine clinical practice. All four were receiving corticosteroids as part of their chemotherapy. We then retrospectively reviewed oncology FDG PET/CT scans over a 2-year period (1,361 scans in 689 patients) to determine the incidence of uptake in white fat by qualitative visual assessment. In the children identified with altered biodistribution, we measured maximum standard uptake value (SUVmax) and mean standard uptake value (SUVmean) in areas of subcutaneous white fat, the buccal regions, body wall or gluteal soft-tissue regions, liver and blood pool. We reviewed all medical records, including medication lists. We summarize the relevant clinical and imaging findings of 13 pediatric patients, including the 4 index patients. We determined the incidence of FDG uptake in white fat to be rare, found in 9 of 1,361 (0.6%) PET scans performed for pediatric cancer evaluation. FDG uptake was increased in subcutaneous adipose tissue, particularly in the buccal regions, body wall and gluteal regions, with a shift of radiotracer away from the blood pool and liver. The degree of increased uptake in peripheral white fat varied from marked to mild, and the biodistribution was distinct from that of brown adipose tissue. Children with this altered biodistribution were uniformly receiving corticosteroids as part of induction treatment for their cancer, and these findings were only identified on post-induction PET/CT. Follow-up PET/CT documented resolution of this effect after treatment with corticosteroids ceased. Our findings support the current understanding that characteristic uptake of FDG in white adipose tissue is mediated by corticosteroid effect. Although this altered biodistribution is rare (

For 45 years, efforts to prepare a fluorinated analogue of the scintiscanning/SPECT agent 6-(iodomethyl)-19-norcholest-5(10)-en-3-ol (NP-59) for development of a PET imaging agent have failed due to undesired elimination reactions and unexpected rearrangements observed­ while utilizing a wide variety of fluorinating conditions (e.g., cesium­ fluoride, silver fluoride, (2-chloro-1,1,2-trifluoroethyl)diethylamine (FAR), diethylaminosulfur trifluoride (DAST), and hexa­fluoro­propene diethylamine FPA). Herein, we report the full synthesis of NP-59, followed by the four-step synthesis of 6-(fluoromethyl)-19-norcholest-5(10)-en-3-ol (FNP-59) using a recently developed mild fluorinating reagent, less prone to producing elimination reactions in the preparation of primary fluorides, TBAF(pinacol)2, with an overall yield of 16% (four steps). Also included is an evaluation of the TBAF(pinacol)2 reagent on eight test substrates to investigate its scope.

Patient-specific dosimetry in radiopharmaceutical therapy (RPT) is impeded by the lack of tools that are accurate and practical for the clinic. Our aims were to construct and test an integrated voxel-level pipeline that automates key components (organ segmentation, registration, dose-rate estimation, and curve fitting) of the RPT dosimetry process and then to use it to report patient-specific dosimetry in (177)Lu-DOTATATE therapy. Methods: An integrated workflow that automates the entire dosimetry process, except tumor segmentation, was constructed. First, convolutional neural networks (CNNs) are used to automatically segment organs on the CT portion of one post-therapy SPECT/CT scan. Second, local contour intensity–based SPECT--SPECT alignment results in volume-of-interest propagation to other time points. Third, dose rate is estimated by explicit Monte Carlo (MC) radiation transport using the fast, Dose Planning Method code. Fourth, the optimal function for dose-rate fitting is automatically selected for each voxel. When reporting mean dose, we apply partial-volume correction, and uncertainty is estimated by an empiric approach of perturbing segmentations. Results: The workflow was used with 4-time-point (177)Lu SPECT/CT imaging data from 20 patients with 77 neuroendocrine tumors, segmented by a radiologist. CNN-defined kidneys resulted in high Dice values (0.91–0.94) and only small differences (2%–5%) in mean dose when compared with manual segmentation. Contour intensity–based registration led to visually enhanced alignment, and the voxel-level fitting had high R(2) values. Across patients, dosimetry results were highly variable; for example, the average of the mean absorbed dose (Gy/GBq) was 3.2 (range, 0.2–10.4) for lesions, 0.49 (range, 0.24–1.02) for left kidney, 0.54 (range, 0.31–1.07) for right kidney, and 0.51 (range, 0.27–1.04) for healthy liver. Patient results further demonstrated the high variability in the number of cycles needed to deliver hypothetical threshold absorbed doses of 23 Gy to kidney and 100 Gy to tumor. The uncertainty in mean dose, attributable to variability in segmentation, averaged 6% (range, 3%–17%) for organs and 10% (range, 3%–37%) for lesions. For a typical patient, the time for the entire process was about 25 min (∼2 min manual time) on a desktop computer, including time for CNN organ segmentation, coregistration, MC dosimetry, and voxel curve fitting. Conclusion: A pipeline integrating novel tools that are fast and automated provides the capacity for clinical translation of dosimetry-guided RPT.

Multiple-time-point SPECT/CT imaging for dosimetry is burdensome for patients and lacks statistical efficiency. A novel method for joint kidney time–activity estimation based on a statistical mixed model, a prior cohort of patients with complete time–activity data, and only 1 or 2 imaging points for new patients was compared with previously proposed single-time-point methods in virtual and clinical patient data. Methods: Data were available for 10 patients with neuroendocrine tumors treated with (177)Lu-DOTATATE and imaged up to 4 times between days 0 and 7 using SPECT/CT. Mixed models using 1 or 2 time points were evaluated retrospectively in the clinical cohort, using the multiple-time-point fit as the reference. Time–activity data for 250 virtual patients were generated using parameter values from the clinical cohort. Mixed models were fit using 1 (∼96 h) and 2 (4 h, ∼96 h) time points for each virtual patient combined with complete data for the other patients in each dataset. Time-integrated activities (TIAs) calculated from mixed model fits and other reduced-time-point methods were compared with known values. Results: All mixed models and single-time-point methods performed well overall, achieving mean bias < 7% in the virtual cohort. Mixed models exhibited lower bias, greater precision, and substantially fewer outliers than did single-time-point methods. For clinical patients, 1- and 2-time-point mixed models resulted in more accurate TIA estimates for 94% (17/18) and 72% (13/18) of kidneys, respectively. In virtual patients, mixed models resulted in more than a 2-fold reduction in the proportion of kidneys with |bias| > 10% (6% vs. 15%). Conclusion: Mixed models based on a historical cohort of patients with complete time–activity data and new patients with only 1 or 2 SPECT/CT scans demonstrate less bias on average and significantly fewer outliers when estimating kidney TIA, compared with popular reduced-time-point methods. Use of mixed models allows for reduction of the imaging burden while maintaining accuracy, which is crucial for clinical implementation of dosimetry-based treatment.

BACKGROUND Postoperative radioactive iodine (RAI) administration is widely utilized in patients with differentiated thyroid cancer. While beneficial in select patients, it is critical to recognize the potential negative sequelae of this treatment. The prevention, diagnosis, and management of the salivary and lacrimal complications of RAI exposure are addressed in this consensus statement. METHODS A multidisciplinary panel of experts was convened under the auspices of the American Head and Neck Society Endocrine Surgery and Salivary Gland Sections. Following a comprehensive literature review to assess the current best evidence, this group developed six relevant consensus recommendations. RESULTS Consensus recommendations on RAI were made in the areas of patient assessment, optimal utilization, complication prevention, and complication management. CONCLUSION Salivary and lacrimal complications secondary to RAI exposure are common and need to be weighed when considering its use. The recommendations included in this statement provide direction for approaches to minimize and manage these complications.

[Image: see text] PD-132301, an inhibitor of sterol O-acyltransferase 1 (SOAT1; also known as acyl-coenzyme A:cholesterol acyltransferase-1, ACAT1), is under clinical investigation for numerous adrenal disorders. Radiolabeled SOAT1 inhibitors could support drug discovery and help diagnose SOAT1-related disorders, such as atherosclerosis. We synthesized two radiolabeled SOAT1 inhibitors, [(11)C]PD-132301 and fluorine analogue [(18)F]1. Rat biodistribution studies were conducted with both agents and, as the most selective tracer, [(11)C]PD-132301 was advanced to preclinical positron emission tomography studies in (atherosclerotic) ApoE(–/–) mice. The uptake of [(11)C]PD-132301 in SOAT1-rich tissue warrants further investigation into the compound as an atherosclerosis and adrenal imaging agent.

Objective To evaluate the success rate of therapeutic administration of a single calculated 131I activity for eliminating hyperthyroidism due to Graves’ disease. Methods and materials Patients with Graves’ hyperthyroidism underwent pinhole thyroid imaging, 24-h radioactive iodine uptake (RAIU) measurements and clinical examination and received a calculated 131I activity of 0.2 mCi per estimated gram of thyroid tissue, adjusted for the 24-h RAIU. The goal of RAI treatment was to achieve hypothyroidism within 3–6 months of 131I administration. Response to RAI therapy was assessed at 7 weeks and 3 months by clinical and biochemical follow-up. Results The study included 316 hyperthyroid patients with Graves’ disease (F238:M78, mean age 42.1 ± 16 y, 4–94). 179 patients (56.6%) had no prior therapeutic intervention (treatment-naive patients), whereas 6 patients had prior thyroid surgery, and 131 (41.5%) had been treated with anti-thyroid medications. The mean estimated thyroid gland size was 50.2 g ± 18, range 15–100. Mean RAIU was 0.57 ± 0.17 (normal 0.07–0.30). RAI doses ranged from 5 to 70 mCi (mean dose = 18.1 mCi). Successful treatment of hyperthyroidism at our institution was obtained after a single therapeutic 131-I activity administration in 295 of 316 (93.3%) patients. Multivariate logistic regression analysis demonstrated that failure of 131I therapy was associated with previous PTU therapy (p 90%) of patients, adjusting for the thyroid size and 24 h uptake measurement.

Objective: Postpartum thyroiditis presents as thyrotoxicosis from autoimmune thyroid inflammation that causes release of iodothyronines and diffuse, decreased thyroid uptake of both radioactive iodine and 99mTc-pertechnetate. Thyroiditis with focal “cold” thyroid nodule on thyroid scintigraphy has been previously described and attributed to localized inflammation.Methods: We report a patient diagnosed with postpartum thyroiditis, in whom an apparently “hot” nodule on initial thyroid pinhole scintigraphy was later noted to be “cold” at follow-up imaging.Results: Thyroid nodularity co-existing with subacute thyroiditis usually presents as focal “cold” nodules, attributed to localized inflammation in the thyroid. The diagnosis of postpartum thyroiditis in our patient was made more challenging due to the presence of a thyroid nodule with an evolving imaging appearance over time. This led to a potential for misdiagnosis of this “hot” nodule dependent on the timing of having the thyroscintigram performed early in the disease course. We hypothesized that the overactive focus of uptake was due to sparing of a pre-existing colloid nodule by the inflammatory process which later became “cold” in the recovery phase.Conclusion: The presence of co-existing thyroiditis and thyroid nodules, both common entities, may cause diagnostic difficulty on thyroid scintigraphy due to dynamic, temporal changes in imaging appearance and the variable findings reported in the literature. Clinical surveillance and performing repeat thyroid imaging will allow correct diagnosis and appropriate management of these challenging cases.Abbreviation: RAIU radioactive iodine uptake

In addition to gastroenteropancreatic neuroendocrine neoplasms, a wide variety of tumors express somatostatin receptors. Somatostatin receptor imaging, heavily utilized in neuroendocrine oncology, may also have utility in the diagnosis of other neoplasms and raises the possibility of potential therapeutic options. We describe the case of a 60-year-old man who underwent 68Ga-DOTATATE PET/CT, demonstrating an avid invasive pituitary macroadenoma. This mass was persistent and refractory despite traditional treatment options. Because of the avidity, 177Lu-DOTATATE therapy was offered, although not ultimately performed, demonstrating a potential treatment for challenging cases utilizing the principles of theranostics.

Purpose Blood glucose is routinely measured prior to 18F-fluorodeoxyglucose (FDG) administration in positron emission tomography (PET) imaging to identify hyperglycemia that may affect image quality. In this study we explore the effects of blood glucose levels upon semi-quantitative standardized uptake value (SUV) measurements of target organs and tissues of interest and in particular address the relationship of blood glucose to FDG accumulation in the brain and liver.

Adrenal lesions are routinely encountered incidentally in clinical practice. Although most of these lesions are benign, malignancy needs to be excluded. Therefore, the initial clinical workup is to exclude aggressive characteristics suggesting malignancy and to identify characteristics predictive of the most common benign lesion, an adrenal adenoma. Predicting a benign adenoma using a variety of imaging modalities has been widely studied using unenhanced computed tomography (CT), contrast enhanced CT, and magnetic resonance (MR) imaging. This review article describes the currently used imaging protocols and clinical interpretation criteria of common adrenal lesions. An adenoma can be predicted if a homogenous soft tissue adrenal mass demonstrates low attenuation (upper threshold value of 10 Hounsfield Units) on unenhanced CT, demonstrates an absolute enhancement washout of ≥ 60% and/or relative enhancement washout of ≥ 40% on adrenal washout contrast enhanced CT, or demonstrates signal loss in opposed-phased MR imaging. If an adrenal adenoma cannot be predicted based upon these criteria, the lesion should be evaluated for other imaging characteristics that suggest a specific pathology, such as an adrenal cyst or myelolipoma. Although nonspecific and with limitations, 18F-fluorodeoxyglucose (FDG) PET/CT has a potential role for differentiating benign from malignant lesions based upon the amount of radiopharmaceutical uptake with malignant lesions generally having greater uptake. If clinical and/or hormonal screening suggests a pheochromocytoma, consideration can be given to 18F-dihydroxyphenylalanine (DOPA) or 123I-metaiodobenzylguanidine (MIBG) in addition to CT and MR. Finally, this review proposes a diagnostic work-up strategy for routine use in clinical practice.

Background The purpose of this study was to evaluate the predictive value of positron emission tomography (PET)-CT in identifying occult nodal metastasis in clinically and radiographically N0 patients with recurrent laryngeal cancer undergoing salvage laryngectomy. Methods Retrospective review of 46 clinically and radiographically N0 patients with recurrent laryngeal cancer who underwent a PET-CT examination before salvage laryngectomy with neck dissection from January 1, 2002, to December 31, 2014, was performed. Results Two patients (16.7%) had true-positive PET-CT results, whereas 10 patients (83.3%) had false-negative scans, 1 patient (2.9%) had a false-positive result and 33 patients (97.1%) had a true-negative PET-CT. The sensitivity of PET-CT was 16.7% (95% confidence interval [CI], 3.5% to 46.0%) with a specificity of 97.1% (95% CI, 83.8% to 99.9%), positive predictive value (PPV) of 66.7% (95% CI, 20.2% to 94.4%), and negative predictive value (NPV) of 76.7% (95% CI, 62.1% to 87.0%). Conclusion PET-CT has poor sensitivity and NPV making PET-CT an imperfect predictor of nodal disease in recurrent laryngeal cancer. © 2017 Wiley Periodicals, Inc. Head Neck 39: 980-987, 2017.

Background Myofascial release (MR) on the posterior thoracolumbar fascia (PLF) is one of the manual techniques aim to restore the normal length and tension of restricted fasciae and muscles. Objectives The present study aimed to quantify the immediate effects of MR on fascial properties of the PLF in healthy men. Design Cross-sectional study. Method Participants (N = 10, aged 22.8 ± 2.0 years) performed a press-down to maximal voluntary contraction (MVC) in the prone position. Deformation of the PLF was measured using an ultrasonographic apparatus. Force output was simultaneously measured. The stiffness index and hysteresis index were then represented by the slope of the loading curve, and the percentage of the area within the loading–unloading curve. One-way ANCOVA was used to compare differences in the stiffness index or hysteresis index of the PLF before and after MR. Two-way repeated ANOVA was used to compare deformation of the PLF or force output after MR. Results The primary findings included a decrease (before: 24.1 ± 8.3 vs. after: 18.9 ± 5.3 N/mm; mean difference, −5.2 ± 4.9 N/mm, p = 0.002 50% = 6.5 ± 1.8 mm and Def 100% = 9.8 ± 1.9 mm vs. after: Def 50% = 6.4 ± 2.5 mm and Def 100% = 10.2 ± 2.4 mm; p = 0.037 Conclusion After MR, stiffness of the PLF decreased in healthy men.

Sites of infection and inflammation can be misleading in oncology PET/CT imaging because these areas commonly show 18F-FDG activity. Caution in the interpretation must be taken to avoid the misdiagnosis of malignancy. Utilization of both CT findings as well as patient history can help differentiate benign infectious and inflammatory processes from malignancy, although occasionally additional work-up may be required. This article discusses the mechanism of 18F-FDG uptake in infection and inflammation with illustrative examples.

Purpose: Hyperglycemia affects FDG uptake in the brain, potentially emulating Alzheimer’s disease in normal individuals. This study investigates global and regional cerebral FDG uptake as a function of plasma glucose in a cohort of patients. Methods: 120 consecutive male patients with FDG PET/CT for initial oncologic staging (July–Dec 2015) were reviewed. Patients with dementia, cerebrovascular accident, structural brain lesion, prior oncology treatment or high metabolic tumor burden (recently shown affecting brain FDG uptake) were excluded. 53 (24 nondiabetic) eligible patients (age 65.7 ± 2.8 mean ± SE) were analyzed with parametric computer software, MIMneuro™. Regional Z-scores were evaluated as a function of plasma glucose and age using multi variable linear mixed effects models with false discovery analysis adjusting for multiple comparisons. If the regression slope was significantly (p

Lingual thyroid is a rare abnormality of thyroid development that is usually treated conservatively with levothyroxine replacement. Rarely, it becomes large enough to cause obstructive symptoms in the oral cavity, requiring definitive treatment.This study reports on three patients with lingual thyroid treated with radioactive iodine-131 ((131)I) with successful radioablation of their ectopic thyroid tissues. Measurement of 24-hour radioactive iodine uptake within thyroidal tissues and hybrid single-photon emission computed tomography/computed tomography imaging using either iodine-123 or technetium-99m pertechnetate scans were performed in all patients demonstrating the location and size of lingual thyroid and absence of an orthotopic thyroid gland.The aim of this study was to describe nonsurgical management of obstructive lingual thyroid tissue with (131)I therapy for lingual thyroid radioablation. Patients were prepared with a low-iodine diet and levothyroxine withdrawal prior to radioablation for optimizing (131)I uptake in ectopic thyroid tissues. Hybrid single-photon emission computed tomography/computed tomography measurement of anatomic size of lingual thyroid tissue and radioactive iodine uptake guided the selection of therapeutic doses, resulting in administration of 10.7, 17.5, and 15.4 mCi of (131)I, respectively. There were no post-therapy complications, and clinical follow-up demonstrated resolution of obstructive oropharyngeal symptoms.Ectopic lingual thyroid tissue is rarely associated with obstructive oropharyngeal symptoms due to progressive enlargement. Radioiodine therapy with (131)I is an effective treatment modality for ablation of ectopic thyroid tissue as an alternative to surgery.

The purpose of this study was to evaluate the clinical utility of Deauville scores in interpretation of end-of-chemotherapy FDG PET scans.Deauville scores improve the clinical utility of end-of-chemotherapy PET, as evidenced by an increase in positive predictive value to 72.7% from 44.4% on the basis of report alone. The negative predictive value remains greater than 95%.

OBJECTIVE: Frostbite is a localized cold-thermal injury resulting from prolonged exposure of flesh to freezing and near freezing temperatures. The depth and extent of frostbite injuries are not easily assessed, from a clinical standpoint, at the time of injury making it challenging to plan appropriate management and treatment. METHODS: A review of the literature of management of cold-related injuries and retrospective case review of the imaging and clinical course of frostbite injury. RESULTS: Bone scintigraphy with single photon emission computed tomography (SPECT)/CT was performed in the acute and subacute course of frostbite injuries, subsequently leading to earlier definitive management and shorter hospital stay. CONCLUSION: Multiphase technetium-99m-methylenediphosphonate ((99)mTc-MDP) bone scintigraphy with SPECT/CT can expedite clinical management of frostbite injuries by determining the extent of injury and can accurately predict the level of amputation if needed. ADVANCES IN KNOWLEDGE: SPECT/CT is underutilized at many facilities but can have a profound and immediate impact on clinical management of patients with frostbite when used in combination with physiological bone scan imaging.

Painful osseous metastasis resulting from castration-resistant prostate carcinoma is a common clinical problem. Historically, nuclear medicine offered several palliative beta-emitting radiopharmaceuticals targeting the skeleton with the goal of decreasing pain. However, these have largely been replaced by the alpha-emitting agent 223radium (Ra). 223Ra received Food and Drug Administration approval in 2013 for the treatment of metastatic castration-resistant prostate cancer with symptomatic bone metastases without visceral metastases. 223Ra offers an improved therapeutic profile due to its alpha-particle emissions resulting in a relatively higher linear energy transfer and lower particle range compared with beta-emitters. 223Ra also has demonstrated to increase overall survival in patients and to delay adverse skeletal events. Running a successful clinical nuclear therapy program with Ra requires a multidisciplinary team approach and this article suggests an implementation strategy from the authors' institution. Potential new nuclear radiopharmaceuticals still under investigation offering the future possibility of radioligand therapy are also discussed briefly.

Vesicoureteral reflux after renal transplantation is associated with increase risk of urinary tract infections, renal scarring, and graft failure. We describe a case of a 46-year-old woman with 2 transplant kidneys, one functioning and another nonfunctioning, presenting with pelvic pain after a bilateral periureteral bulking procedure. Diuretic renography was performed to exclude iatrogenic ureteral obstruction. This showed a normally functioning transplant kidney without obstruction and subsequent vesicoureteral reflux into the collecting system of the nonfunctioning transplant kidney. This inadvertent indirect nuclear cystogram illustrates an unusual imaging presentation of a common disease process requiring further treatment.

Purpose To examine the effect metabolic burden (tumor and/or cardiac myocyte uptake) has on fluorine 18 fluorodeoxyglucose (FDG) distribution in organs and tissues of interest. Materials and Methods Positron emission tomographic (PET)/computed tomographic (CT) scans at the Ann Arbor Veterans Affairs hospital from January to July 2015 were reviewed. A total of 107 scans (50 patients; mean age, 64.3 years ± 13.2 [standard deviation]) had metabolic tissue burden assessed by using total lesion glycolysis (TLG) obtained from autosegmentation of the tumor and/or cardiac tissue. Standardized uptake value (SUV) and subsequent normalized SUV uptake in target organs and tissues were compared with 436 FDG PET/CT scans previously reported in 229 patients as a function of TLG to describe the effect(s) that metabolic burden has on reference tissue (blood pool, liver, and brain) FDG uptake. Subsequent regression by using linear mixed-effects models was used. If the slope of the regression was significantly (P.05) different than zero, then an effect from TLG was present. Results There was a negative inverse relationship (P.0001) between FDG uptake within reference tissues (blood pool, liver, and brain) and TLG in comparison to the study population at similar blood glucose levels. This TLG effect was no longer statistically significant (P.05) when FDG uptake was normalized to a reference tissue (eg, blood pool or liver). Conclusion Metabolic tissue burden can have a significant effect on SUV measurements for PET imaging. This effect can be mitigated by normalizing FDG uptake to a reference tissue.

Introduction: Primary paraganglioma (PG) of the thyroid gland is an extremely rare neuroendocrine tumor with potential for misdiagnosis. We describe 2 cases of thyroid PG, suggest a possible diagnostic and therapeutic management strategy, and present a systematic review of the literature. Case Reports: Two 67-year-old women presented similarly with asymptomatic but rapidly growing thyroid nodules in which malignancy was suspected after fine needle aspiration biopsy, “THY 4” according to the 2014 SIAPEC classification, both undergoing total thyroidectomy. Unexpectedly, immunohistochemistry showed neuroendocrine cellular architecture that was negative for common markers of well-differentiated follicular neoplasms, thyroglobulin, thyroid transcription factor 1, cytokeratins and medullary thyroid cancer, calcitonin, carcinoembryonic antigen, whereas neuron-specific enolase, synaptophysin, chromogranin A, and S-100 protein were highly expressed, confirming the diagnosis of primary thyroid PG. The patients were both discharged on postoperative day 2, without any other therapy and are currently well without evidence of local recurrence of metastatic disease, after 4 years and 3 months of follow-up, respectively. Discussion: These are the only 2 cases of thyroid PG experienced in our center which specializes in thyroid surgery. Thyroid PG is a rare neuroendocrine neoplasm first described by Van Miert in 1964 with just over 50 cases reported in the literature. Our experience is concordant with the literature that the diagnosis of the primary PG of the thyroid is challenging, due to its low prevalence and the cytologic and histopathologic similarities with other more frequently diagnosed benign and malignant thyroid tumors. Immunohistochemistry is required for definitive diagnosis but gross tumor characteristics are also helpful for diagnosis. Surgical resection is the recommended standard treatment.

In addition to nuclear cardiac and breast imaging, Tc-sestamibi scintigraphy is often used to localize parathyroid adenomas. F- fluorodeoxyglucose (FDG) PET is heavily utilized in oncology, although its use in identifying parathyroid adenomas is limited. We describe a case of a 57-year-old woman who underwent parathyroid scintigraphy and F-FDG PET/CT in the same week due to hyperparathyroidism and an enlarging breast mass, respectively. A right paratracheal mediastinal mass that otherwise would be suspicious for nodal metastases by CT alone was correctly identified to be an ectopic parathyroid adenoma using a combination of the nuclear medicine studies performed.

The use of preablation diagnostic radioiodine scans for risk stratification and radioiodine therapy planning for differentiated thyroid cancer (DTC) remains controversial.The objective was to assess the contribution of preablation diagnostic 131-I scans with SPECT/CT (Dx 131-I scan) to (1) the risk stratification and (2) the postoperative management of DTC.The study was designed as a prospective sequential patient series.The study was conducted at a University hospital.Three hundred twenty patients (pts) with DTC (219F; 101M, mean age 47.3 ± 16.4 y, range 10-90) were studied.Using clinical and histopathology information an endocrinologist performed risk stratification and determined postoperative management with respect to radioiodine therapy (RAI) planning. The decision to withhold or to administer RAI, and the recommended low, medium or high therapeutic 131-I activity were recorded. Dx 131-I scans were performed and interpreted by two nuclear medicine physicians as showing thyroid remnant, cervical nodal, or distant metastases. The endocrinologist then reperformed risk stratification and reformulated management after consideration of Dx 131-I scans and stimulated thyroglobulin (Tg) information.Main outcome measures were changes in risk stratification and management after Dx 131-I scans.Detection of unsuspected nodal and distant metastases and elevated stimulated Tg levels resulted in a change in the estimated risk of recurrence in 15% of patients, and management in 31% of patients, as compared to initial risk stratification and management based on histopathology alone.Both imaging data and stimulated thyroglobulin levels acquired at the time of Dx 131-I scans are consequential for 131-I therapy planning, providing information that changes risk stratification in 15% of patients as compared to recurrence risk estimation based on histopathology alone. Dx 131-I scans contribute to risk stratification by defining residual nodal and distant metastatic disease, changing clinical management in 29.4% of patients.

The aim of the study was to determine the diagnostic utility of parathyroid scintigraphy with technetium-99m (99mTc)-sestamibi single-photon emission computed tomography/computed tomography (SPECT/CT) for localization of parathyroid adenoma.We performed a systematic search of medical databases PubMed and Medline/OVID for literature on 99mTc-sestamibi SPECT/CT parathyroid scintigraphy, using the search terms hyperparathyroidism, parathyroid adenoma/hyperplasia, SPECT/CT, and SPECT-CT. Citations for 981 articles and 128 abstracts of full articles were reviewed by two coauthors for relevance. Twenty-four peer-reviewed studies on SPECT/CT parathyroid scintigraphy qualified for inclusion. The Quality Assessment of Diagnostic Accuracy Studies-2 tool was used to assess study quality. Meta-analytical techniques were used to obtain pooled estimates of the parathyroid adenoma localization rate using a random-effects model.A total of 24 studies published between January 2003 and March 2014 with 1276 patients (334 men, 762 women, and 180 of unspecified sex) met the inclusion criteria. Data on the test performance of dual-phase 99mTc-sestamibi SPECT/CT showed an estimated pooled sensitivity (per-patient analysis) of 0.86 [confidence interval (CI) 0.81-0.90]. Sensitivity of SPECT/CT was superior to that of SPECT (0.74; CI 0.66-0.82) and planar (0.70; CI 0.61-0.80) techniques. Heterogeneity was present in the reported literature (I2=80.3%). The rate of ectopic parathyroid adenomas ranged between 4 and 20% and SPECT/CT was superior to SPECT and planar imaging for localization of ectopic sites.Utilization of SPECT/CT fusion imaging for 99mTc-sestamibi parathyroid scintigraphy improves the test performance compared with planar and SPECT imaging; it assists preoperative planning for a minimally invasive surgical approach for the neck and is of value in subgroups with ectopic glands or coexisting nodular thyroid disease.

Objective This study aimed to (1) compare the agreement of two evaluation methods of metabolic response in patients with non-small cell lung cancer (NSCLC) and determine their prognostic value and (2) explore an optimal cutoff of metabolic reduction to distinguish a more favorable subset of responders. Methods This is a secondary analysis of prospective studies. Enrolled patients underwent 18F-PET/CT within 2 weeks before, during, and months after radiotherapy (post-RT). Metabolic response was assessed using both Peter MacCallum (PM) method of qualitative visual assessment and University of Michigan (UM) method of semiquantitative measurement. The agreement between two methods determined response, and their prediction of outcome was analyzed. Results Forty-four patients with median follow-up of 25.2 months were analyzed. A moderate agreement was observed between PM- and UM-based response assessment (Kappa coefficient = 0.434), unveiling a significant difference in CMR rate (p = 0.001). Categorical responses derived from either method were significantly predictive of overall survival (OS) and progression-free survival (PFS) (p Conclusions There was a modest discrepancy in metabolic response rates between PM and UM criteria, though both could offer predictive classification for survival. The percentage decrease provides an ordinal value that correlates with prolonged survival, recommending 75 % as the optimal threshold at identifying better responders.

Blood glucose is routinely measured prior to436 FDG PET/CT consecutive studies performed for oncology staging in 229 patients (226 male) at the Ann Arbor Veterans Administration Healthcare System were reviewed. All patients had blood glucose measured (112.4±34.1mg/dL) prior to injection of 466.2±51.8MBq (12.6±1.4mCi) of FDG. SUV measurements of brain, aortic arch blood-pool, liver, and spleen were obtained at 64.5±10.2min' post-injection.We found a negative inverse relationship of brain SUV with increasing plasma glucose, levels for both absolute and normalized (either to blood-pool or liver) values. Higher blood glucose levels had a mild effect upon liver and blood-pool SUV. By contrast, spleen SUV was independent of blood glucose, but demonstrated the greatest variability (deviation on linear regression). In contrast to other tissues, liver and spleen SUV normalized to blood-pool SUV were not dependent upon blood glucose levels.The effects of hyperglycemia upon FDG uptake in brain and liver, over a range of blood glucose values generally considered acceptable for clinical PET imaging, may have measurable effects on semi-quantitative image analysis.

The purpose of this study was to systematically review the utility of single-photon emission tomography–computed tomography (SPET–CT) fusion imaging in the investigation of thyroid cancer. We performed a systematic search of the world literature on radionuclide SPET–CT imaging of thyroid cancer using the medical databases Medline (OVID) and PubMed. The following search terms were used to identify relevant studies: (a) thyroid, combined with (b) SPECT/CT or SPECT–CT or SPET/CT or SPET–CT. The electronic searches returned citations for 1,189 potentially eligible articles and 98 abstracts were reviewed for relevance by two co-authors. Thirty-one peer-reviewed full articles reporting the utility, value and diagnostic performance of radioiodine SPET–CT for the imaging of well-differentiated thyroid cancer were selected. The quality of these studies was assessed using the quality assessment of diagnostic accuracy studies-2 tool. As there was heterogeneity in the studies, a systematic review analysis was conducted as our chosen research synthesis method. A total of 31 studies published between 2003 and 2014 report the utility of radioiodine SPET–CT. These studies uniformly found incremental diagnostic value of I-123 and I-131 SPET–CT over SPET and/or planar imaging. SPET–CT allows accurate characterization of radioiodine uptake in the neck and at distant sites, clarifies equivocal foci of radioactivity, improves specificity for disease, and evaluates benign physiological etiologies. Additional pilot uses of SPET–CT have been reported, e.g., for thyroid nodule evaluation, medullary thyroid cancer work-up, and investigation of lingual thyroid. Radioiodine SPET–CT fusion imaging of thyroid cancer has incremental utility, improving image interpretation as compared to planar and SPET imaging. It is likely to see more widespread application in the future.

The diagnosis of dementia syndromes can be challenging for clinicians, particularly in the early stages of disease. Patients with higher education levels may experience a marked decline in cognitive function before their dementia is detectable with routine testing methods. In addition, comorbid conditions (eg, depression) and the use of certain medications can confound the clinical assessment. Clinicians require a high degree of certainty before making a diagnosis of Alzheimer disease or some other neurodegenerative disorder, since the impact on patients and their families can be devastating. Moreover, accurate diagnosis is important because emerging therapeutic regimens vary depending on the cause of the dementia. Clinically based testing is useful; however, the results usually do not enable the clinician to make a definitive diagnosis. For this reason, imaging biomarkers are playing an increasingly important role in the workup of patients with suspected dementia. Positron emission tomography with 2-[fluorine-18]fluoro-2-deoxy-D-glucose allows detection of neurodegenerative disorders earlier than is otherwise possible. Accurate interpretation of these studies requires recognition of typical metabolic patterns caused by dementias and of artifacts introduced by image processing. Although visual interpretation is a vital component of image analysis, computer-assisted diagnostic software has been shown to increase diagnostic accuracy.

Summary Background To determine whether the addition of molecular and imaging biomarkers to established clinical risk factors could help predict locoregional failure (LRF) after chemoradiation in human papillomavirus (HPV)-related (+) oropharyngeal cancer (OPC) and improve patient selection for locoregional treatment de-intensification. Methods HPV status was determined for 198 consecutive patients with stage III/IV OPC treated with definitive chemoradiation from 5/2003 to 10/2010. The impact of pre-therapy epidermal growth factor receptor (EGFR) overexpression; imaging biomarkers including primary tumor and nodal maximum standardized uptake values on FDG-PET, gross tumor volumes, and matted nodes; and clinical factors on LRF (including residual disease at adjuvant neck dissection) was assessed. Results Primary tumors were HPV+ in 184 patients and HPV-negative in 14. EGFR overexpression was related to HPV-negative status and was univariately associated with LRF in the overall population, but was neither retained in the multivariate model after adjustment for HPV status, nor associated with LRF in HPV+ patients. Similarly, imaging biomarkers were univariately associated with LRF, but correlated with T-stage and/or N-stage and did not remain predictive in HPV+ patients after adjustment for T4- and N3-stages, which were the only significant predictors of LRF on multivariate analysis. Among HPV+ patients with non-T4- or N3-stages, only minimal smoking was associated with decreased LRF. Conclusions The prognostic impact of EGFR overexpression and imaging biomarkers on LRF was predominantly related to their association with HPV-negative status and T- or N-stage, respectively. Among HPV+ OPC patients treated with uniform chemoradiation, only T4-stage, N3-stage, and smoking contributed to risk-stratification for LRF.

Endocrine tumors are hormonally active benign or malignant neoplasms arising within endocrine organs or from specialized cells of the amine precursor uptake and decarboxylation system. The detection rate of these tumors is increasing as a result of sensitive biochemical tests and high-resolution diagnostic imaging. Medical imaging has become a key component in the diagnosis and staging of endocrine malignancies; however, despite the impressive advances in computed tomography (CT) and MRI, detection of small primary tumors and metastases continues to be a challenge. Functional imaging techniques use radiopharmaceuticals targeted at unique tumor cellular processes in order to provide sensitive and highly specific whole-body imaging. Functional imaging allows prediction of the efficacy of radionuclide or receptor-based therapies and surveillance after therapy. Advances in imaging have not been limited to radiopharmaceuticals. Hybrid scanner technology in the form of PET/CT and single photon emission computed tomography (SPECT)/CT, designed to combine functional images with anatomic maps, has further improved the diagnostic accuracy. High-resolution hybrid imaging when deployed with novel PET and SPECT radiopharmaceuticals has the potential to dramatically change, individualize, and optimize imaging plans based on the histological grade, degree of differentiation, and genetic profile of each patient's endocrine neoplasm.

Sites of infection and inflammation can be misleading in oncology PET/CT imaging because these areas commonly show 18F-FDG activity. Caution in the interpretation must be taken to avoid the misdiagnosis of malignancy. Utilization of both CT findings as well as patient history can help differentiate benign infectious and inflammatory processes from malignancy, although occasionally additional work-up may be required. This article discusses the mechanism of 18F-FDG uptake in infection and inflammation with illustrative examples.

Oral activity on radioiodine scintigraphy is commonly seen and may cause diagnostic dilemma. Determining the precise mechanism of oral uptake on radioiodine scintigraphy will increase the accuracy and confidence of interpretation and avoid possible misinterpretation.To determine the etiology of focal persistent radioiodine oral uptake seen on radioiodine scans.Retrospective sequential series at a university clinic and a phantom study experiment.Preablation iodine-131 planar and single photon emission computed tomography/computed tomography (SPECT/CT) scans of 216 patients after total thyroidectomy were reviewed. Planar images were inspected for the presence of oral activity above the salivary gland background and SPECT/CT was reviewed to determine the location and nature of oral activity. A post-hoc phantom study was designed using typodont stone models fitted with various dental materials, immersed in a diluted iodine-131 solution, and imaged with SPECT/CT to characterize radioiodine uptake by high-attenuation dental materials.Oral activity was seen on planar images in 123 of 216 (57%) patients; 12 patients were excluded from analysis because the SPECT/CT field of view did not cover the entire oral cavity. In the remainding 111 patients SPECT/CT images demonstrated focal uptake localizing to high-attenuation dental material on the CT in 95 of 111 (86%) patients. All cases of oral activity on planar imaging were interpreted as benign etiology on SPECT/CT. The phantom study confirmed focal in vitro uptake within high-attenuation dental materials representing a range of commonly used metal alloys.Focal oral activity on diagnostic radioiodine scans frequently localizes to high-attenuation dental material on SPECT/CT. We postulate that an affinity between negatively charged iodide ions (I(-)) in saliva and positively charged metal ions (eg, Ag(+), Hg(+), Au(2+), Pd(2+)) within the dental materials is at the basis of persistent focal radioiodine uptake in the oral cavity. This represents a new mechanism underlying benign radioiodine activity not previously described in the medical literature.

Radioiodine imaging has a well-established role in depicting metastatic disease after thyroidectomy in patients with well-differentiated thyroid cancer. Uptake of radioiodine in thyroid metastases depends on expression of sodium-iodide symporter (NIS) by tumor tissues. However, because radioiodine may also accumulate in normal structures and tissues, it is important to distinguish physiologic radioiodine activity from metastatic disease. Furthermore, secretions that contain radioiodine may also simulate pathologic uptake. A spectrum of physiologic distributions, normal variants, and benign mimics of disease have been described in the literature; yet, even when armed with a comprehensive knowledge of these patterns, interpreting radiologists and nuclear physicians may still encounter diagnostic uncertainty. Single-photon emission computed tomography (SPECT) with integrated computed tomography (CT) is a novel technology that, when applied to diagnostic iodine 123 or iodine 131 ((131)I) radioiodine scintigraphy, may accurately localize and help distinguish benign mimics of disease, with the potential to alter the management plan. SPECT/CT is increasingly being used with radioiodine scintigraphy to evaluate patients with thyroid cancer and shows promise for improving imaging specificity and reducing false-positive results.

Nuclear medicine traditionally employs planar and single photon emission computed tomography (SPECT) imaging techniques to depict the biodistribution of radiotracers for the diagnostic investigation of a range of disorders of endocrine gland function. The usefulness of combining functional information with anatomy derived from computed tomography (CT), magnetic resonance imaging (MRI), and high resolution ultrasound (US), has long been appreciated, either using visual side-by-side correlation, or software-based co-registration. The emergence of hybrid SPECT/CT camera technology now allows the simultaneous acquisition of combined multi-modality imaging, with seamless fusion of 3D volume datasets. Thus, it is not surprising that there is growing literature describing the many advantages that contemporary SPECT/CT technology brings to radionuclide investigation of endocrine disorders, showing potential advantages for the pre-operative locating of the parathyroid adenoma using a minimally invasive surgical approach, especially in the presence of ectopic glands and in multiglandular disease. In conclusion, hybrid SPECT/CT imaging has become an essential tool to ensure the most accurate diagnostic in the management of patients with hyperparathyroidism.

Squamous cell carcinoma is the most frequent malignancy of the head and neck region, accounting for 5% of all malignant tumors worldwide. Accurate staging at diagnosis is critical for selection of appropriate treatment strategy. A variety of therapeutic options are used for treatment, including surgery with or without radical dissection, lymph node dissections of various severities, radiotherapy, chemotherapy, and combinations of these. Precise prediction of the extent of primary tumors, detection of unknown primary tumor, cervical lymph node status, and distant metastatic spread is important for treatment planning and prognosis. Accurate evaluation of these factors prior to treatment helps guide surgical extent or radiation porta, minimizing locoregional treatment failure.

The objective of this study was to detect regional patterns of cardiac sympathetic denervation in idiopathic Parkinson disease (IPD) using 11C-hydroxyephedrine (11C-HED) PET and determine the denervation rate over 2 y. Methods: We obtained 62 cardiac 11C-HED PET scans in 39 patients (30 men and 9 women; mean age ± SD, 61.9 ± 5.9 y), including 23 patients with follow-up scans at 2 y. We derived 11C-HED retention indices (RIs; mL of blood/min/mL of tissue) reflecting nerve density and integrity for 480 left ventricular (LV) sectors. We compared IPD patients with 33 healthy controls using z score analysis; RI values ≤ 2.5 SDs were considered abnormal. We expressed global and regional LV denervation as the percentage extent of z score severity and severity-extent product (SEP) on 9-segment bullseye maps and decline in cardiac sympathetic innervation as the 2-y difference in SEP (diff-SEP). Results: Baseline 11C-HED PET in the 39 IPD patients revealed an RI mean of 0.052 ± 0.022 mL of blood/min/mL of tissue. In comparison with data from normal controls, 12 patients had normal 11C-HED PET, 5 showed mild denervation (percentage extent < 30%), and 22 had moderate to severe denervation (percentage extent > 30%, z score ≤ 2.5 SD). In the 23 paired PET scans, worsening cardiac denervation (global diff-SEP > 9) occurred in 14 of 23 (60.9%) patients over 2 y, including percentage LV abnormality (59% increasing to 66%), z-severity (–2.4 down to –2.5), and SEP (–195 to –227) (P = 0.0062). We found a mean annual decline of 4.6% ± 5.6 (maximum, 13%) in 11C-HED retention from a baseline global RI mean of 0.0481 ± 0.0218 to 0.0432 ± 0.0220 (P = 0.0009). At baseline, 5 patients with normal uptake had no interval change; 3 with mild denervation developed interval decline in lateral and inferior segments (diff-SEP –82 to –99) compared with anterior and septal segments (–65 to –79), whereas the reverse pattern occurred in 15 patients with severe baseline denervation. Conclusion: Progressive decline in cardiac sympathetic neural integrity in IPD patients occurs at a modest rate over 2 y on 11C-HED scans with marked heterogeneity and a regional pattern of involvement and decline.

Adrenocortical cancer (ACC) is an uncommon primary neoplasm of the adrenal cortex with dismal prognosis. It often presents with symptoms and signs of adrenal cortical hormone hypersecretion and abdominal mass effect or is incidentally detected as an adrenal mass on imaging performed for other indications. Endocrine evaluation, comprehensive staging, and meticulous resection are crucial to ensure the best possible outcome. Despite extensive initial surgical resection, local and distant metastases are not uncommon with disappointing 5-year survival, although progress is being made at high-volume centers. Accurate restaging of recurrent disease is important to guide further management. Mitotane, external beam radiation and chemotherapy, and newer anticancer systemic treatments are used as adjunctives for inoperable disease and distant metastases. Contrast-enhanced CT and MRI are first-line imaging modalities for evaluation of ACC to characterize adrenal masses and to determine tumor resectability. Emerging literature supports F-FDG PET/CT use to determine the malignant potential of adrenal masses. In patients with a diagnosis of ACC, FDG PET/CT is sensitive for detecting metastatic disease, and its tumor accumulation has been correlated to pathology, Weiss scores, and prognosis. Metomidate, labeled with C for PET or with I for SPECT/CT, allows characterization of an adrenal mass as being of adrenocortical origin with high specificity. Taking advantage of its adrenocortical avidity, metomidate has been labeled with I for radionuclide therapy in a subset of ACC. In this review, we describe how nuclear medicine imaging, and specifically PET, can assist surgical management of ACC.