Papillary Thyroid Cancer, Small Cell Lung Cancer, and Parathyroid Adenoma Synchronously Visualized on 99m Tc-MIBI SPECT/CT in a Patient With Hyperparathyroidism : Comparison With 18 F-FDG PET/CT.

ABSTRACT: 99m Tc-MIBI scintigraphy is a nuclear medicine imaging modality commonly used for the preoperative localization of parathyroid adenomas in patients with hyperparathyroidism. In addition, 99m Tc-MIBI can also be used for imaging various tumors due to its unique mechanism of intracellular accumulation. Here, we introduced a case of a single 99m Tc-MIBI SPECT/CT simultaneously visualized two different malignant tumors, such as papillary thyroid cancer and small cell lung cancer, along with a parathyroid adenoma in a patient with hyperparathyroidism. The clinical usefulness of 99m Tc-MIBI SPECT/CT was also explored by comparing it with 18 F-FDG PET/CT among the three tumors.

Intratumoral 99mTc-DPD Uptake on Bone Scintigraphy in a Patient With Invasive Micropapillary Breast Carcinoma: A Pathologic Review.

ABSTRACT: Invasive micropapillary carcinoma (IMPC) is a rare and aggressive subtype of breast cancer with a poorer prognosis due to high local recurrence and lymphovascular invasion. Interestingly, IMPC often does not show suspicious patterns of calcifications related to malignancy on mammography. Therefore, the lack of suspicious calcifications makes it difficult to detect breast cancer on mammography. With only nonspecific calcifications on mammography, we observed an unusual intratumoral 99mTc-DPD uptake on whole-body bone scintigraphy in an IMPC breast cancer patient during the initial staging workup, and its characteristics were compared with mammographic findings and the postoperative pathologic features.

Extrastriatal Accumulation of 18 F-FP-CIT at Cerebral Infarction in a Patient With Suspected Parkinson Disease.

ABSTRACT: 18 F-FP-CIT PET/CT is a useful diagnostic tool for differentiating between idiopathic Parkinson disease and atypical Parkinson syndrome by visualizing the striatum, where the nerve endings of nigrostriatal dopaminergic neurons are located. We present an unusual accumulation of 18 F-FP-CIT in the infarct and peri-infarct brain area of an 83-year-old man who was referred for the management of suspected cerebral infarction due to sudden dysarthria and delirium.

Optimal Protocol and Clinical Usefulness of 123I-MIBG Cardiac Scintigraphy for Differentiation of Parkinson's Disease and Dementia with Lewy Body from Non-Parkinson's Diseases.

Purpose: 123I-metaiodobenzylguanidine (MIBG) cardiac scintigraphy was a useful imaging modality for the diagnosis of Parkinson's disease, but its diagnostic performances were variably reported. This retrospective study compared the diagnostic performances and investigated the optimal imaging protocol of 123I-MIBG cardiac scintigraphy at various imaging time points in patients suspected of Parkinson's disease in clinical practice. Methods: In patients suspected of Parkinson's disease, clinical records, autonomic function tests, and 123I-MIBG cardiac scintigraphy were retrospectively reviewed. Semi-quantitative parameters such as heart-to-mediastinum ratio (HMR) and washout rate (WR) were calculated and compared at 15 min, 1 h, 2 h, 3 h, and 4 h post-injection (p.i.). of 123I-MIBG cardiac scintigraphy. Group A consisted of Parkinson's disease (PD), Parkinson's disease dementia (PDD), and dementia with Lewy body (DLB), and group B consisted of non-Parkinson's diseases such as multiple system atrophy (MSA), progressive supranuclear palsy (PSP), drug-induced parkinsonism (DIP), essential tremor (ET), Parkinson-plus syndrome (PPS), and unspecified secondary parkinsonism (NA). The diagnostic performances of HMR and WR were compared for differentiation of group A from group B, and their clinical usefulness and optimal imaging time points were explored. Results: Seventy-eight patients were included in group A (67 PD, 7 PDD, 4 DLB), and 18 patients were included in group B (5 MSA, 3 PSP, 2 DIP, 2 ET, 1 PPS, and 1 NA). Sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value of HMR and WR were maximized at 4 h p.i., (82.1%, 85.7%, 82.6%, 97.0%, and 46.2%; cutoff threshold < 1.717; area under curve 0.8086) and at the time interval between 1 and 4 h p.i. (65.4%, 85.7%, 68.5%, 96.2%, and 30.8%; cutoff threshold > 24.1%; area under curve 0.8246), respectively, and PPVs of both HMR and WR persistently showed greater than 92.7% at earlier time points and shorter time intervals. Conclusion: This study reassured that 4-h-delayed imaging is recommended for the best diagnostic performances in 123I-MIBG cardiac scintigraphy. Although it showed suboptimal diagnostic performances to differentiate PD, PDD, and DLB from non-Parkinson's diseases, it can be useful as an auxiliary measure for the differential diagnosis in usual clinical practice. Supplementary Information: The online version contains supplementary material available at 10.1007/s13139-023-00790-w.

Incidentally Found Soft Tissue 99mTc-DPD Uptake on Bone Scintigraphy Was Useful in an Early Diagnosis of Peripheral Arterial Disease.

Peripheral arterial disease (PAD) is a critical disease which is presented by occlusion of peripheral arteries, while it could result in amputation of the involved limbs if it remained untreated before it would progress into tissue necrosis. It is usually diagnosed by CT angiography or conventional angiography, but its early diagnosis is challenging because its symptoms may be absent or like those of other diseases. In this case report, the authors showed that an atypical soft tissue uptake of lower limb incidentally found on a bone scintigraphy resulted in early diagnosis and successful treatment outcome of PAD.

Analysis of treatment pattern of anti-dementia medications in newly diagnosed Alzheimer's dementia using OMOP CDM.

Anti-dementia medications are widely prescribed to patients with Alzheimer's dementia (AD) in South Korea. This study investigated the pattern of medical management in newly diagnosed patients with AD using a standardized data format-the Observational Medical Outcome Partnership Common Data Model from five hospitals. We examined the anti-dementia treatment patterns from datasets that comprise > 5 million patients during 2009-2019. The medication utility information was analyzed with respect to treatment trends and persistence across 11 years. Among the 8653 patients with newly diagnosed AD, donepezil was the most commonly prescribed anti-dementia medication (4218; 48.75%), followed by memantine (1565; 18.09%), rivastigmine (1777; 8.98%), and galantamine (494; 5.71%). The rising prescription trend during observation period was found only with donepezil. The treatment pathways for the three cholinesterase inhibitors combined with N-methyl-D-aspartate receptor antagonist were different according to the drugs (19.6%; donepezil; 28.1%; rivastigmine, and 17.2%; galantamine). A 12-month persistence analysis showed values of approximately 50% for donepezil and memantine and approximately 40% for rivastigmine and galantamine. There were differences in the prescribing pattern and persistence among anti-dementia medications from database using the Observational Medical Outcome Partnership Common Data Model on the Federated E-health Big Data for Evidence Renovation Network platform in Korea.

Clinical Significance of the Circle of Willis in Patients with Symptomatic Internal Carotid Artery Occlusion.

BACKGROUND: Despite improvements in medical treatment, many patients experience ischemic stroke owing to internal carotid artery occlusion. We retrospectively evaluated a novel method based on the arterial structure of the circle of Willis (CoW) to identify patients at a high risk of recurrent stroke. METHODS: The study enrolled 104 patients with symptomatic occlusion of the internal carotid artery. CoW integrity was evaluated by a quantitative scoring system based on conventional angiography. Patients were categorized into a good integrity (n = 45) or poor integrity (n = 59) group. Primary endpoint was early neurologic deterioration, recurrent ischemic stroke, or transient ischemic attack. RESULTS: History of ischemic stroke before initial presentation was more prevalent in the poor integrity group (22.2% vs. 47.5%, P = 0.01), and there were no differences between the 2 groups in terms of stroke risk factors. Overall estimated rate of the primary endpoint was 25.6% 2 years after angiography. It was 5.7% in the good integrity group and 39.8% in the poor integrity group (P < 0.001). In a Cox regression analysis, male sex (P = 0.01, hazard ratio = 6.60), use of a tissue plasminogen activator (P = 0.00, hazard ratio = 6.10), and poor integrity of CoW (P = 0.00, hazard ratio = 5.42) were risk factors for the primary endpoint. Patients in the poor integrity group with decreased vascular reserve experienced frequent primary endpoint events compared with patients in the good integrity group (P = 0.00). CONCLUSIONS: Patients with poor integrity of CoW are vulnerable to recurrent ischemic stroke and appear to require more aggressive treatment.

Decreased Metabolism in the Posterior Medial Network with Concomitantly Increased Metabolism in the Anterior Temporal Network During Transient Global Amnesia.

Perturbation of corticohippocampal circuits is a key step in the pathogenesis of transient global amnesia. We evaluated the spatial distribution of altered cerebral metabolism to determine the location of the corticohippocampal circuits perturbed during the acute stage of transient global amnesia. A consecutive series of 12 patients with transient global amnesia who underwent 18F-fluorodeoxyglucose positron emission tomography within 3 days after symptom onset was identified. We used statistical parametric mapping with two contrasts to identify regions of decreased and increased brain metabolism in transient global amnesia patients compared with 25 age-matched controls. Transient global amnesia patients showed hypometabolic clusters in the left temporal and bilateral parieto-occipital regions that belong to the posterior medial network as well as, hypermetabolic clusters in the bilateral inferior frontal regions that belong to the anterior temporal network. The posterior medial and anterior temporal networks are the two main corticohippocampal circuits involved in memory-guided behavior. Decreased metabolism in the posterior medial network might explain the impairment of episodic memory observed during the acute stage of transient global amnesia. Concomitant increased metabolism within the anterior temporal network might occur as a compensatory mechanism.

Oligomeric forms of amyloid-ß protein in plasma as a potential blood-based biomarker for Alzheimer's disease.

BACKGROUND: Soluble amyloid-ß (Aß) oligomers are the major toxic substances associated with the pathology of Alzheimer's disease (AD). The ability to measure Aß oligomer levels in the blood would provide simple and minimally invasive tools for AD diagnostics. In the present study, the recently developed Multimer Detection System (MDS) for AD, a new enzyme-linked immunosorbent assay for measuring Aß oligomers selectively, was used to detect Aß oligomers in the plasma of patients with AD and healthy control individuals. METHODS: Twenty-four patients with AD and 37 cognitively normal control individuals underwent extensive clinical evaluations as follows: blood sampling; detailed neuropsychological tests; brain magnetic resonance imaging; cerebrospinal fluid (CSF) measurement of Aß42, phosphorylated tau protein (pTau), and total tau protein (tTau); and 11C-Pittsburgh compound B (PIB) positron emission tomography. Pearson's correlation analyses between the estimations of Aß oligomer levels by MDS and other conventional AD biomarkers (CSF Aß42, pTau, and tTau, as well as PIB standardized uptake value ratio [PIB SUVR]) were conducted. ROC analyses were used to compare the diagnostic performance of each biomarker. RESULTS: The plasma levels of Aß oligomers by MDS were higher in patients with AD than in normal control individuals, and they correlated well with conventional AD biomarkers (levels of Aß oligomers by MDS vs. CSF Aß42, r = -0.443; PIB SUVR, r = 0.430; CSF pTau, r = 0.530; CSF tTau, r = 0.604). The sensitivity and specificity of detecting plasma Aß oligomers by MDS for differentiating AD from the normal controls were 78.3% and 86.5%, respectively. The AUC for plasma Aß oligomers by MDS was 0.844, which was not significantly different from the AUC of other biomarkers (p = 0.250). CONCLUSIONS: Plasma levels of Aß oligomers could be assessed using MDS, which might be a simple, noninvasive, and accessible assay for evaluating brain amyloid deposition related to AD pathology.

11C-PIB PET imaging reveals that amyloid deposition in cases with early-onset Alzheimer's disease in the absence of known mutations retains higher levels of PIB in the basal ganglia.

PURPOSE: Early-onset Alzheimer's disease (EOAD) has a different pathologic burden and clinical features compared with late-onset Alzheimer's disease (LOAD). We examined the effects of age at onset on the burden and distribution of ß-amyloid in patients with EOAD, in whom well-characterized mutations associated with Alzheimer's disease were absent. METHODS: We genotyped ApoE, APP, PSEN1 and PSEN2 in the patients with Alzheimer's disease: 9 patients with EOAD (age <65), 11 with LOAD (age >70) and 8 normal controls (NCs), all of whom had undergone 11C-labeled Pittsburgh compound B-positron emission tomography imaging. RESULTS: Patients with EOAD exhibited higher z scores and larger cluster sizes, and retained higher levels of Pittsburgh compound B in the bilateral thalamus and in some parts of the globus pallidus (P<0.05, false discovery rate). CONCLUSION: Distribution of amyloid deposition in EOAD outside the context of genetic mutations topographically showed some differences from that in LOAD.

Analysis of Cerebrospinal Fluid and [11C]PIB PET Biomarkers for Alzheimer's Disease with Updated Protocols.

BACKGROUND: Recently, a Korean research group suggested a consensus protocol, based on the Alzheimer's Disease Neuroimaging Initiative study protocol but with modifications for minimizing the confounding factors, for the evaluation of cerebrospinal fluid (CSF) biomarkers. OBJECTIVE: Here, we analyzed fluid and imaging biomarkers of Alzheimer's disease (AD) in Korean population. We used the updated protocol to propose a more accurate CSF biomarker value for the diagnosis of AD. METHODS: Twenty-seven patients with AD and 30 cognitively normal controls (NC) were enrolled. CSF was collected from 55 subjects (patients with AD = 26, NC = 29) following the Korea consensus protocol. CSF biomarkers were measured using the INNO-BIA AlzBio3 immunoassay, and Pittsburgh compound B (PIB) positron emission tomography (PET) scans were also performed. RESULTS: The cutoff values of CSF amyloid beta 1-42 (Aß42), total tau (t-Tau), and phosphorylated tau (p-Tau) proteins were 357.1 pg/ml, 83.35 pg/ml, and 38.00 pg/ml, respectively. The cutoff values of CSF t-Tau/Aß42 and p-Tau/Aß42 ratio- were 0.210 (sensitivity 100%, specificity 86.21%) and 0.1350 (sensitivity 88.46%, specificity of 92.86%). The concordance rate with PIB-PET was higher using the CSF t-Tau/Aß42 ratio (κ= 0.849, CI 0.71-0.99) than CSF Aß42 alone (κ= 0.703, CI 0.51-0.89). CONCLUSIONS: Here, we improved controversial factors associated with the previous CSF study protocol and suggested a new cutoff value for the diagnosis of AD. Our results showed good diagnostic performance for differentiation of AD. Thus, we expect our findings could be a cornerstone in the establishment and clinical application of biomarkers for AD diagnosis.

Early prediction of response to neoadjuvant chemotherapy in breast cancer patients: comparison of single-voxel (1)H-magnetic resonance spectroscopy and (18)F-fluorodeoxyglucose positron emission tomography.

OBJECTIVES: To prospectively compare performances of single-voxel proton magnetic resonance spectroscopy ((1)H-MRS) and (18)F-fluorodeoxyglucose positron emission tomography (FDG-PET) in predicting pathologic response to neoadjuvant chemotherapy (NAC) in breast cancer patients. METHODS: Thirty-five breast cancer patients who received NAC and subsequent surgery were prospectively enrolled. MRS and FDG-PET were performed before and after the 1st NAC cycle. Percentage changes of total choline-containing compounds (tCho) via MRS, and maximum and peak standardized uptake values (SUVmax, SUVpeak) and total lesion glycolysis (TLG) via FDG-PET were measured, and their performances in predicting pathologic complete response (pCR) were compared. RESULTS: Of the 35 patients, 6 showed pCR and 29 showed non-pCR. Mean % reductions of tCho, SUVmax, SUVpeak, and TLG of the pCR group were larger than those of the non-pCR group (-80.3 ± 13.9 % vs. -32.1 ± 49.4 %, P = 0.025; -54.7 ± 22.1 % vs. -26.3 ± 33.7 %, P = 0.058; -60.7 ± 18.3 % vs. -32.3 ± 23.3 %, P = 0.009; -89.5 ± 8.5 % vs. -52.6 ± 36.2 %, P = 0.020). Diagnostic accuracy (area under ROC curve; Az, 0.911) of the % reduction of tCho was comparable to those of %SUVmax (0.822), SUVpeak (0.862), and TLG (0.879) in distinguishing pCR from non-pCR (all P > 0.05). CONCLUSION: MRS showed comparable performance to FDG-PET in early prediction of pCR in breast cancer patients. KEY POINTS: • MRS can predict response to NAC in breast cancer post-1 (st) cycle. • Changes in tCho and SUV after NAC reflect tumour cellularity changes. • MRS can be an alternative to FDG-PET in predicting response to NAC.

Longitudinal Cerebral Perfusion Change in Transient Global Amnesia Related to Left Posterior Medial Network Disruption.

BACKGROUND: The pathophysiology of transient global amnesia (TGA) is not fully understood. Previous studies using single photon emission computed tomography (SPECT) have reported inconclusive results regarding cerebral perfusion. This study was conducted to identify the patterns of regional cerebral blood flow (rCBF) in TGA patients via longitudinal SPECT analysis. An association between the observed SPECT patterns and a pathophysiological mechanism was considered. METHODS: Based on the TGA registry database of Seoul National University Bundang Hospital, 22 TGA patients were retrospectively identified. The subjects underwent initial Tc-99m-ethyl cysteinate dimer (ECD) SPECT within 4 days of an amnestic event and underwent follow-up scans approximately 6 months later. The difference in ECD uptake between the two scans was measured via voxel-based whole brain analysis, and the quantified ECD uptake was tested using a paired t-test. RESULTS: The TGA patients had significantly decreased cerebral perfusion at the left precuneus (P<0.001, uncorrected) and at the left superior parietal and inferior temporal gyrus according to the voxel-based whole brain analysis (P<0.005, uncorrected). A difference in the quantified ECD uptake between the 2 scans was also found at the left precuneus among the 62 cortical volumes of interest (P = 0.018, Cohen's d = -0.25). CONCLUSION: We identified left hemispheric lateralized hypoperfusion that may be related to posterior medial network disruption. These findings may be a contributing factor to the pathophysiology of TGA.

Comparison of 4D CT, ultrasonography, and 99mTc sestamibi SPECT/CT in localizing single-gland primary hyperparathyroidism.

OBJECTIVE: The present study was designed to evaluate 4D computerized tomography (CT) as a means of localizing abnormal parathyroid glands in primary hyperparathyroidism (HPT). STUDY DESIGN: Case series with expertized image review. SETTING: Tertiary care hospital. SUBJECTS AND METHODS: A total of 38 patients were recruited for study, all of whom had undergone focused parathyroidectomy for single-lesion primary HPT between June 2011 and September 2013. In each patient, 3 imaging procedures were performed: cervical ultrasonography (US), 99mTc-sestamibi SPECT/CT (SeS), and 4D CT. Collective imaging data were blindly reviewed and compared. RESULTS: 4D CT outperformed US and SeS in terms of sensitivity (P=.27), specificity (P=.01), positive predictive value (PPV) (P<.01), negative predictive value (NPV) (P=.19), and accuracy (P<.01). In 7.9% (3/38) of patients, 4D CT provided specific anatomic information that was unaffordable by US and SeS. Localization by 4D CT correlated with tissue parathyroid hormone level (P=.02), maximum diameter (P=.01), and volume (P<.01) of abnormal parathyroid glands. CONCLUSION: 4D CT proved helpful in localizing target parathyroid glands of primary HPT that were missed by traditional imaging.

Correlation of breast cancer subtypes, based on estrogen receptor, progesterone receptor, and HER2, with functional imaging parameters from 68Ga-RGD PET/CT and ¹8F-FDG PET/CT.

PURPOSE: Imaging biomarkers from functional imaging modalities were assessed as potential surrogate markers of disease status. Specifically, in this prospective study, we investigated the relationships between functional imaging parameters and histological prognostic factors and breast cancer subtypes. METHODS: In total, 43 patients with large or locally advanced invasive ductal carcinoma (IDC) were analyzed (47.6 ± 7.5 years old). (68)Ga-Labeled arginine-glycine-aspartic acid (RGD) and (18)F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) were performed. The maximum and average standardized uptake values (SUVmax and SUVavg) from RGD PET/CT and SUVmax and SUVavg from FDG PET/CT were the imaging parameters used. For histological prognostic factors, estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) expression was identified using immunohistochemistry (IHC) or fluorescent in situ hybridization (FISH). Four breast cancer subtypes, based on ER/PR and HER2 expression (ER/PR+,Her2-, ER/PR+,Her2+, ER/PR-,Her2+, and ER/PR-,Her2-), were considered. RESULTS: Quantitative FDG PET parameters were significantly higher in the ER-negative group (15.88 ± 8.73 vs 10.48 ± 6.01, p = 0.02 for SUVmax; 9.40 ± 5.19 vs 5.92 ± 4.09, p = 0.02 for SUVavg) and the PR-negative group (8.37 ± 4.94 vs 4.79 ± 3.93, p = 0.03 for SUVavg). Quantitative RGD PET parameters were significantly higher in the HER2-positive group (2.42 ± 0.59 vs 2.90 ± 0.75, p = 0.04 for SUVmax; 1.60 ± 0.38 vs 1.95 ± 0.53, p = 0.04 for SUVavg) and showed a significant positive correlation with the HER2/CEP17 ratio (r = 0.38, p = 0.03 for SUVmax and r = 0.46, p < 0.01 for SUVavg). FDG PET parameters showed significantly higher values in the ER/PR-,Her2- subgroup versus the ER/PR+,Her2- or ER/PR+,Her2+ subgroups, while RGD PET parameters showed significantly lower values in the ER/PR-,Her2- subgroup versus the other subgroups. There was no correlation between FDG and RGD PET parameters in the overall group. Only the ER/PR-,Her2- subgroup showed a significant positive correlation between FDG and RGD PET parameters (r = 0.59, p = 0.03 for SUVmax). CONCLUSION: (68)Ga-RGD and (18)F-FDG PET/CT are promising functional imaging modalities for predicting biomarkers and molecular phenotypes in breast cancer patients.

Background ¹8F-FDG uptake in positron emission mammography (PEM): correlation with mammographic density and background parenchymal enhancement in breast MRI.

UNLABELLED: We aimed to determine whether background (18)F-FDG uptake in positron emission mammography (PEM) was related to mammographic density or background parenchymal enhancement in breast MRI. METHODS: We studied a total of 52 patients (mean age, 50.9 years, 26 premenopausal, 26 postmenopausal) with newly diagnosed breast cancer who underwent (18)F-FDG PEM (positron emission mammography), conventional mammography and breast MRI. The background mean (18)F-FDG uptake value on PEM was obtained by drawing a user-defined region of interest (ROI) in a normal area of the contralateral breast. We reviewed the mammography retrospectively for overall breast density of contralateral breast according to the four-point scale (grade 1-4) of the Breast Imaging Reporting and Data System (BI-RADS) classification. The background parenchymal enhancement of breast MRI was classified as minimal, mild, moderate, or marked. All imaging findings were interpreted by two readers in consensus without knowledge of image findings of other modalities. RESULTS: Multiple linear regression analysis revealed a significant correlation between background (18)F-FDG uptake on PEM and mammographic density after adjustment for age and menopausal status (P<0.01), but not between background (18)F-FDG uptake on PEM and background parenchymal enhancement on MRI. CONCLUSION: Background (18)F-FDG uptake on PEM significantly increases as mammographic density increases. Background parenchymal enhancement in breast MRI was not an independent predictor of the background (18)F-FDG uptake on PEM unlike mammographic density.

Total lesion glycolysis in positron emission tomography is a better predictor of outcome than the International Prognostic Index for patients with diffuse large B cell lymphoma.

BACKGROUND: This study was undertaken to evaluate the prognostic value of quantitative metabolic parameters in [(18) F]2-fluoro-2-deoxyglucose (FDG)-positron emission tomography (PET) for diffuse large B cell lymphoma (DLBCL). METHODS: A total of 140 DLBCL patients underwent FDG-PET scans before rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone (R-CHOP) chemotherapy. The maximal standardized uptake value (SUVmax ) and total lesion glycolysis (TLG) were calculated, with the margin thresholds as 25%, 50%, and 75% of SUVmax of all lesions. Treatment outcomes were compared between groups according to metabolic parameters and the International Prognostic Index (IPI). RESULTS: After a median follow-up of 28.5 months (range, 5-81 months), the 2-year progression-free survival (PFS) and overall survival (OS) were 83% and 87%, respectively. Among metabolic parameters, TLG at the threshold of 50% (TLG50 ) was significantly associated with treatment outcomes. High TLG50 values (>415.5) were associated with reduced survivals compared with low TLG50 values (≤415.5) (2-year PFS of 73% versus 92%, P = .007; and 2-year OS of 81% versus 93%, P = .031). High IPI score (≥3) significantly reduced OS (2-year OS of 79% versus 90%, P = .049). Ann Arbor stage III/IV adversely affected PFS (P = .013). However, high IPI score and Ann Arbor stage of III/V did not significantly shorten PFS (P = .200) and OS (P = .921), respectively. High TLG50 values independently predicted survivals by multivariate analysis (hazard ratio = 4.4; 95% confidence interval = 1.5-13.1; P = .008 for PFS and hazard ratio = 3.1; 95% confidence interval = 1.0-9.6; P = .049 for OS). CONCLUSIONS: Combined assessment of volume and metabolism (ie, TLG) is predictive of survivals in DLBCL patients who are treated with R-CHOP. Cancer 2013. © 2012 American Cancer Society.

Photo-guided sentinel node mapping in breast cancer using marker-free photo-gamma fusion lymphoscintigraphy.

PURPOSE: Photo-gamma fusion lymphoscintigraphy (PGFLS) was developed by overlying a conventional planar gamma image on a photograph for the guidance of sentinel node biopsy. The feasibility and accuracy of PGFLS was assessed in breast cancer patients. METHODS: A digital camera and a gamma camera were coordinated to obtain photograph and gamma images from the same angle. Using the distance to the object and calibration acquisition with a flat phantom and radioactive markers, PGFLS was performed both in phantom and in patients without fiducial markers. Marker-free PGFLS was verified using flat phantom, anthropomorphic phantom with markers simulating sentinel nodes and breast cancer patients. In addition, the depth of the radioactive marker or sentinel node was calculated using two gamma images taken at right angles. The feasibility and accuracy of PGFLS were assessed in terms of mismatch errors of co-registration and depth with reference to the data from SPECT/CT. RESULTS: The mismatch error was less than 6 mm in the flat phantom image at a distance from 50 to 62 cm without misalignment. In the anthropomorphic phantom study, co-registration error was 0.42 ± 0.29 cm; depth error was 0.51 ± 0.37 cm, which was well correlated with the reference value on SPECT/CT (x scale: R(2) = 0.99, p < 0.01; y scale: R(2) = 0.99, p < 0.01; depth: R(2) = 0.99, p < 0.01). In ten patients with breast cancer referred for lympho-SPECT/CT, PGFSL enabled photo-guided sentinel lymph node mapping with acceptable accuracy (co-registration error, 0.47 ± 0.24 cm; depth error, 1.20 ±0.41 cm). The results from PGFSL showed close correlation with those from SPECT/CT (x scale: R(2) = 0.99, p < 0.01; y scale: R(2) = 0.98, p < 0.01; depth: R(2) = 0.77, p < 0.01). CONCLUSIONS: The novel and convenient PGFLS technique is clinically feasible, showing acceptable accuracy and providing additional visual and quantitative information for sentinel lymph node mapping. This approach will facilitate photo-guided sentinel lymph node dissection in breast cancer.

Detection and Characterization of Parathyroid Adenoma/Hyperplasia for Preoperative Localization: Comparison Between (11)C-Methionine PET/CT and (99m)Tc-Sestamibi Scintigraphy.

PURPOSE: (11)C-Methionine PET/CT (Met-PET/CT) is a useful imaging method for detection of parathyroid adenoma; however, the reported detection rate has been variable. The current study was intended to investigate detection sensitivity and preoperative localization of parathyroid adenoma (PA) or parathyroid hyperplasia (PH) on Met-PET/CT compared with (99m)Tc-sestamibi (MIBI) scintigraphy in patients with primary hyperparathyroidism (HPT) or suspected PA. METHODS: Met-PET/CT and MIBI scintigraphy images were reviewed by two nuclear medicine physicians unaware of pathologic results. Detection sensitivities and preoperative localization of detected parathyroid tissues into five predefined segments were evaluated by visual assessment and semi-quantitative analysis with ratio of standardized uptake values (SUVR) between parathyroid tissue and normal lung as reference. Linear regression analysis with SUVR and serum parathyroid hormone (sPTH) was performed for characterization of PA or PH. Predicted PTH (pPTH) was calculated and compared with sPTH in PH and PA. Each pPTH was obtained for a calculated SUVR by using linear regression model from the result of previous linear regression analysis between SUVR and sPTH. RESULTS: In 16 patients, detection sensitivities of Met-PET/CT and MIBI scintigraphy were 91.7 % (11/12) and 41.7 % (5/12) for PA and PH including both biopsy-confirmed and clinically-suspected cases, and 100 % (8/8) and 50 % (4/8) for pathologically confirmed PA and PH cases only, respectively. Met-PET/CT showed higher performance than MIBI scintigraphy in localization of parathyroid tissues; correct localization rate was 87.5 % (7/8) on Met-PET/CT and 50 % (4/8) on MIBI scintigraphy. In semi-quantitative analysis, SUVR was linearly associated with sPTH by linear regression analysis (sPTH = 39.53 × SUVR - 89.84, p = 0.0383). There was a borderline significant difference in pPTH between PH and PA (35.1 vs 204.7 ± 164.0, p = 0.052), while there was no significant difference in sPTH between PH and PA (289 vs 230.4 ± 160.4, p = 0.305). CONCLUSIONS: Met-PET/CT has a potential to be a useful diagnostic modality for preoperative detection and localization of parathyroid tissues with higher sensitivity than MIBI scintigraphy, and for characterization of PA or PH.

Imaging sensitivity of dedicated positron emission mammography in relation to tumor size.

Positron emission mammography (PEM) has been reported to have higher sensitivity than whole-body positron emission tomography (PET)due to higher spatial resolution. However, no direct evidence exists regarding the imaging sensitivity of PEM related to lesion size. In the present study, imaging sensitivity of PEM was investigated in relation to pathologically confirmed tumor size. A total of 113 breast lesions from 101 patients were included in the analysis. The patients underwent (18)F-fluorodeoxyglucose (FDG) PEM and whole-body PET/computed tomography (CT) before surgical resection, and images were analyzed visually and quantitatively using the tumor-to-normal-tissue uptake ratio (TNR). Tumors were classified into four groups based on size using pathologic results, and sensitivities of PEM and PET/CT were compared in the overall subjects and in each size group. In visual analysis, PEM showed significantly higher imaging sensitivity than PET/CT (95% vs. 87%; P = 0.004), which was more definite in the small-tumor groups. In quantitative analysis, the TNR of PEM was significantly higher than that of PET/CT in the small-tumor groups, whereas no difference was found in the overall group. With a cutoff TNR of 2.5, PEM showed significantly higher sensitivity than PET/CT in the overall and small-tumor groups. In conclusion, PEM had higher imaging sensitivity than PET/CT, particularly in small tumors. The results suggest that PEM may be used for diagnosis and characterization of small lesions as a supplementary imaging modality for PET/CT.