Nuclear Medicine Specialists Research Articles

Detection of cardiac amyloidosis on routine bone scintigraphy: an important gatekeeper role for the nuclear medicine physician

Cardiac amyloidosis (CA)—mostly transthyretin-related (ATTR-CA)—has recently gained interest in cardiology. Bone scintigraphy (BS) is one of the main screening tools for ATTR-CA but also used for various other reasons. The objective was to evaluate whether all CA cases are detected and what happens during follow-up. All routine BS performed at the Maastricht University Medical Center (May 2012–August 2020) were screened for the presence of CA. Scans performed for suspected CA were excluded. A Perugini stage ≥1 was classified as positive necessitating further examination. The electronic medical record system was evaluated for any contact with cardiology or other specialists until 2021. Of the 2738 BS evaluated, 40 scans (1.46%; median age 73.5 [IQR: 65.8–79.5], 82.5% male) were positive (Perugini grade 1: 31/77.5%, grade 2: 6/15%, grade 3: 3/7.5%); the potential diagnosis ATTR-CA was not seen in 38 patients (95%) by the nuclear medicine specialist. During follow-up, 19 out of those 40 patients (47.5%) underwent cardiac evaluation without diagnosing CA. Available echocardiograms of patients with a positive BS showed left ventricular hypertrophy, a preserved ejection fraction, and diastolic dysfunction ≥2 in 9/47%, 10/53%, and 4/21% of patients, respectively. Additionally, 20 (50%) patients presented to at least one specialty with symptoms indicative of cardiac amyloidosis. The prevalence of a positive BS indicating potential CA in an unselected population is low but substantial. The majority was not detected which asks for better awareness for CA of all involved specialists to ensure appropriate treatment and follow-up.Graphical abstract

Novel indices representing heterogeneous distributions of myocardial perfusion imaging

IntroductionHeterogeneous distribution in myocardial perfusion images (MPI) obtained by scintigraphy is often observed in cardiac diseases with normal myocardial perfusion. However, quantitative assessments of such heterogeneity have not been established. We hypothesized that the heterogeneity in MPI can be quantitatively evaluated through histogram analysis, calculating the standard deviation (SD), the 95% bandwidth (BW95%), and entropy.MethodsWe examined resting 99mTc-MIBI images in 20 healthy subjects and 29 patients with cardiac disease who had none or very-mild reduced myocardial perfusion evaluated as a low summed rest score (0 to 4, the range of the studied healthy subjects). Two nuclear medicine specialists blindly divided them into two groups: non-heterogeneity or heterogeneity group, based solely on their visual assessments of heterogeneity on splash and polar maps generated from single-photon emission computed tomography (SPECT) images. The %uptake was determined by dividing the tracer count of each pixel by the tracer count of the pixel with the highest value in the LV myocardium. SD, BW95%, and entropy from histogram patterns were analyzed from the polar map data array of each %uptake. We investigated whether heterogeneity could be assessed using SD, BW95, and entropy in two groups classified by visual assessments. Additionally, we evaluated the area under the curve (AUC) to identify heterogeneity in the receiver operating characteristic curve analysis.ResultsBased solely on visual assessments, 11 (22%) and 38 (78%) cases were classified into the non-heterogeneity and heterogeneity groups, respectively. The non-heterogeneity group consisted of only healthy subjects, and all patients with cardiac disease were classified into the heterogeneity group. The cases in the heterogeneity group had significantly higher values of heterogeneity indices (SD, BW95%, and entropy) in %uptake than those in the non-heterogeneity group (p < 0.05 for all). The AUCs of the heterogeneity indices were sufficiently high (AUCs > 0.90 for all) in distinguishing cases with visually heterogeneous distribution or patients with cardiac disease.ConclusionsHeterogeneity in MPI can be evaluated using SD, BW95%, and entropy through histogram analysis. These novel indices may help identify patients with subtle myocardial changes, even in images that show preserved perfusion (345/350).

Two lymphoma histotypes and papillary thyroid carcinoma coexisting on Hashimoto ground: a case report and review of the literature

BackgroundPapillary carcinoma is the most frequent type of thyroid carcinoma, while primary thyroid lymphoma is uncommon disease. The coexistence of these entities has already been described, and the common risk factor is considered Hashimoto thyroiditis. The two most frequent histotypes of primary thyroid lymphoma are diffuse large B-cell and mucosa-associated lymphoid tissue lymphoma, but the coexistence of both with papillary carcinoma is rarely reported.MethodsWe present a case of a previously healthy 57-years old male with rapidly growing lump on the right side of the neck. Ultrasonography revealed nodules in both thyroid lobes. Fine needle aspiration cytology and pertechnetate scintigraphy were performed. Due to the Bethesda T-5 in the “cold” nodule of the right lobe, surgery with histopathological and immunohistochemistry analysis was indicated.ResultsHistopathological and immunohistochemistry methods confirmed concomitant malignancies in the thyroid gland: diffuse large B-cell lymphoma and papillary carcinoma in the right, and mucosa-associated lymphoid tissue lymphoma in the left lobe with Hashimoto thyroiditis in the remaining tissue. Patient underwent therapy procedures and was without signs of local recurrence or metastatic spread on subsequent follow-up.ConclusionsSudden appearance of the neck mass in patients with Hashimoto thyroiditis should raise suspicion on primary thyroid lymphoma and be promptly taken in the diagnostic workup, including fine needle aspiration cytology. Pathology with immunohistochemistry is crucial for further clinical decision making. Since the standardized protocol in management of these complex patients is missing, personal approach and close collaboration between cytologist, pathologist, surgeon, haematologist and nuclear medicine specialist is essential.

Rebooting nuclear medicine specialist education under the COVID-19 pandemic: From plenary lectures to active e-learning.

Despite major reforms of specialist training in the Nordic countries towards concrete learning outcomes and promoting active learning, most specialist courses continue to be based on lectures. We redesigned our mandatory 5-day course in clinical nuclear medicine (NM) that was last held in 2016 towards active learning. Thirty 1-h lectures were replaced with 10 thematic blocks of 3 h each. Each block was taught by a single teacher in a blend of short introductory lectures alternating with small groups of residents reading NM cases from our newly established national case library in diagnostic format. Due to COVID-19, the entire course in 2021 needed to be run on a videoconferencing system rather than in a computer laboratory as had been originally planned. At the end of the course, we conducted the same anonymized survey as in 2016. All 19 course participants responded. 74% fully agreed that the e-course format had been 'good'. One hundred per cent fully agreed that the practical exercises were 'useful' versus 50% in 2016 (p < 0.001). In their free text answers on the merits or downsides of e-learning, 12/12 respondents only mentioned advantages. Our newly established library of anonymized teaching cases within our national health network is an effective tool for organising courses based on active learning. Despite the change towards distance learning enforced by the pandemic, course participants reported the same high levels of satisfaction with active learning in small groups as in the earlier traditional lecture-based course format.

Current barriers and recommendations on the diagnosis of transthyretin amyloid cardiomyopathy: a Delphi study

ObjectivesThis study has been conducted to investigate the non-invasive diagnostic journey of patients with a transthyretin amyloid cardiomyopathy (aTTR-CM) in Turkey, identify the challenges and uncertainties encountered on the path to diagnosis from the perspectives of expert physicians, and develop recommendations that can be applied in such cases.MethodsThis study employed a three-round modified Delphi method and included 10 cardiologists and five nuclear medicine specialists. Two hematologists also shared their expert opinions on the survey results related to hematological tests during a final face-to-face discussion. A consensus was reached when 80% or more of the panel members marked the “agree/strongly agree” or “disagree/strongly disagree” option.ResultsThe panelists unanimously agreed that the aTTR-CM diagnosis could be established through scintigraphy (using either 99mTc-PYP, 99mTc-DPD, or 99mTc-HMPD) in a patient with suspected cardiac amyloidosis (CA) without a further investigation if AL amyloidosis is ruled out (by sFLC, SPIE and UPIE). In addition, scintigraphy imaging performed by SPECT or SPECT-CT should reveal a myocardial uptake of Grade ≥2 with a heart-to-contralateral (H/CL) ratio of ≥1.5. The cardiology panelists recommended using cardiovascular magnetic resonance (CMR) and a detailed echocardiographic scoring as a last resort before considering an endomyocardial biopsy in patients with suspected CA whose scintigraphy results were discordant/inconclusive or negative but still carried a high clinical suspicion of aTTR-CM.ConclusionThe diagnostic approach for aTTR-CM should be customized based on the availability of diagnostic tools/methods in each expert clinic to achieve a timely and definitive diagnosis.

CXCR4-targeted Theranostics in Hematooncology: Opportunities and Challenges.

C-X-C motif chemokine receptor 4 (CXCR4) is overexpressed in a multitude of cancers, including neoplasms of hematopoietic origin. This feature can be leveraged by a theranostic approach, which provides a read-out of the actual CXCR4 expression in vivo, followed by CXCR4-targeted radioligand therapy (RLT) exerting anti-cancer as well as myeloablative efficacy. In a recent meeting of hematooncology and nuclear medicine specialists, statements on the current clinical practice and future perspectives of this innovative concept were proposed and summarized in this opinion article. Experts concluded that i) CXCR4-directed [68Ga]Ga-PentixaFor PET/CT has the potential to improve imaging for patients with marginal zone lymphoma; ii) CXCR4-targeted RLT exerts anti-lymphoma efficacy and myeloablative effects in patients with advanced, treatment-refractory T-cell lymphomas; iii) prospective trials with CXCR4-based imaging and theranostics are warranted.

Verification of the effect of data-driven brain motion correction on PET imaging.

Brain positron emission tomography/computed tomography (PET/CT) scans are useful for identifying the cause of dementia by evaluating glucose metabolism in the brain with F-18-fluorodeoxyglucose or Aβ deposition with F-18-florbetaben. However, since imaging time ranges from 10 to 30 minutes, movements during the examination might result in image artifacts, which interfere with diagnosis. To solve this problem, data-driven brain motion correction (DDBMC) techniques are capable of performing motion corrected reconstruction using highly accurate motion estimates with high temporal resolution. In this study, we investigated the effectiveness of DDBMC techniques on PET/CT images using a Hoffman phantom, involving continuous rotational and tilting motion, each expanded up to approximately 20 degrees. Listmode imaging was performed using a Hoffman phantom that reproduced rotational and tilting motions of the head. Brain motion correction processing was performed on the obtained data. Reconstructed images with and without brain motion correction processing were compared. Visual evaluations by a nuclear medicine specialist and quantitative parameters of images with correction and reference still images were compared. Normalized Mean Squared Error (NMSE) results demonstrated the effectiveness of DDBMC in compensating for rotational and tilting motions during PET imaging. In Cases 1 and 2 involving rotational motion, NMSE decreased from 0.15-0.2 to approximately 0.01 with DDBMC, indicating a substantial reduction in differences from the reference image across various brain regions. In the Structural Similarity Index (SSIM), DDBMC improved it to above 0.96 Contrast assessment revealed notable improvements with DDBMC. In continuous rotational motion, % contrast increased from 42.4% to 73.5%, In tilting motion, % contrast increased from 52.3% to 64.5%, eliminating significant differences from the static reference image. These findings underscore the efficacy of DDBMC in enhancing image contrast and minimizing motion induced variations across different motion scenarios. DDBMC processing can effectively compensate for continuous rotational and tilting motion of the head during PET, with motion angles of approximately 20 degrees. However, a significant limitation of this study is the exclusive validation of the proposed method using a Hoffman phantom; its applicability to the human brain has not been investigated. Further research involving human subjects is necessary to assess the generalizability and reliability of the presented motion correction technique in real clinical scenarios.

Formulating a national position statement and guide on modern theranostics in the Philippines.

Barriers to the establishment of advanced technologies in developing countries were overcome when modern theranostics pertaining to the use of Ga-68 and Lu-177 PSMA and DOTATATE were first offered to patients in the Philippines in early 2018. However, significant growth was not experienced at St. Luke's Medical Center for five years and lutetium was not yet distributed to other institutions by a radiopharmaceutical supplier. Due to the relative novelty and rapid expansion of theranostics worldwide, position statements were released by the Australasian Association of Nuclear Medicine Specialists, European Association of Nuclear Medicine, Society of Nuclear Medicine and Molecular Imaging, and International Atomic Energy Agency primarily to uphold patient safety and ensure a level of standard among its practitioners. Subsequently in the latter half of 2022, these were adopted and modified according to what is feasible and applicable locally within the Philippine Society of Nuclear Medicine, considering the current status and future possibilities. Different representatives were involved, and several groups were mobilized for successful implementation. A liability clause was incorporated to discourage unprofessional acts.

Infective Native Aortic Aneurysm: a Delphi Consensus Document on Treatment, Follow Up, and Definition of Cure

Evidence is lacking to guide the management of infective native aortic aneurysm (INAA). The aim of this study was to establish expert consensus on surgical and antimicrobial treatment and follow up, and to define when an INAA is considered cured. Delphi methodology was used. The principal investigators invited 47 international experts (specialists in infectious diseases, radiology, nuclear medicine, and vascular and cardiothoracic surgery) via email. Four Delphi rounds were performed, three weeks each, using an online questionnaire with initially 28 statements. The panellists rated the statements on a five point Likert scale. Comments on statements were analysed, statements were revised and added or deleted, and the results were presented in the iterative rounds. Consensus was defined as ≥ 75% of the panel rating a statement as strongly agree or agree on the Likert scale, and consensus on the final assessment was defined as Cronbach's alpha > 0.80. All 49 panellists completed all four rounds, resulting in 100% participation. One statement was added based on the results and comments of the panel, resulting in 29 final statements: three on need for consensus, 20 on treatment, five on follow up, and one on definition of cure. All 29 statements reached agreement of ≥ 86%. Cronbach's alpha increased for each consecutive round; round 1, 0.85; round 2, 0.90; round 3, 0.91; and round 4, 0.94. Thus, consensus was reached for all statements. INAAs are rare, and high level evidence to guide optimal management is lacking. This consensus document was established with the aim of helping clinicians manage these challenging patients, as a supplement to current guidelines. The presented consensus will need future amendments in accordance with newly acquired knowledge.

Estimation of kinetic parameters in dynamic FDG PET imaging based on shortened protocols: a virtual clinical study.

This study investigated the estimation of kinetic parameters and production of related parametric Ki images in FDG PET imaging using the proposed shortened protocol (three 3-min/bed routine static images) by means of the simulated annealing (SA) algorithm.Six realistic heterogeneous tumors and various levels of [18F] FDG uptake were simulated by the XCAT phantom. An irreversible two-tissue compartment model (2TCM) using population-based input function was employed. By keeping two routine clinical scans fixed (60-min and 90-min post injection), the effect of the early scan time on optimizing the estimation of the pharmacokinetic parameters was investigated. The SA optimization algorithm was applied to estimate micro- and macro-parameters (K1, k2, k3, Ki).The minimum bias for most parameters was observed at a scan time of 20-min, which was < 10%. A highly significant correlation (> 0.9) as well as limited bias (< 10%) were observed between kinetic parameters generated from twomethods [two-tissue compartment full dynamic scan (2TCM-full) and two-tissue compartment by SA algorithm (2TCM-SA)]. The analysis showed a strong correlation (> 0.8) between (2TCM-SA) Ki and SUV images. In addition, the tumor-to-background ratio (TBR) metric in the parametric (2TCM-SA) Ki images was significantly higher than SUV, although the SUV images provide better Contrast-to-noise ratio relative to parametric (2TCM-SA) Ki images.The proposed shortened protocol by the SA algorithm can estimate the kinetic parameters in FDG PET scan with high accuracy and robustness. It was also concluded that the parametric Ki images obtained from the 2TCM-SA as a complementary image of the SUV possess more quantification information than SUV images and can be used by the nuclear medicine specialist. This method has the potential to be an alternative to a full dynamic PET scan.

Metabolic tumour volume in Hodgkin lymphoma-A comparison between manual and AI-based analysis.

To compare total metabolic tumour volume (tMTV), calculated using two artificial intelligence (AI)-based tools, with manual segmentation by specialists as the reference. Forty-eight consecutive Hodgkin lymphoma (HL) patients staged with [18F] fluorodeoxyglucose positron emission tomography/computed tomography were included. The median age was 35 years (range: 7-75), 46% female. The tMTV was automatically measured using the AI-based tools positron emission tomography assisted reporting system (PARS) (from Siemens) and RECOMIA (recomia.org) without any manual adjustments. A group of eight nuclear medicine specialists manually segmented lesions for tMTV calculations; each patient was independently segmented by two specialists. The median of the manual tMTV was 146 cm3 (interquartile range [IQR]: 79-568 cm3) and the median difference between two tMTV values segmented by different specialists for the same patient was 26 cm3 (IQR: 10-86 cm3). In 22 of the 48 patients, the manual tMTV value was closer to the RECOMIA tMTV value than to the manual tMTV value segmented by the second specialist. In 11 of the remaining 26 patients, the difference between the RECOMIA tMTV and the manual tMTV was small (<26 cm3, which was the median difference between two manual tMTV values from the same patient). The corresponding numbers for PARS were 18 and 10 patients, respectively. The results of this study indicate that RECOMIA and Siemens PARS AI tools could be used without any major manual adjustments in 69% (33/48) and 58% (28/48) of HL patients, respectively. This demonstrates the feasibility of using AI tools to support physicians measuring tMTV for assessment of prognosis in clinical practice.

Clinical value of 18F-fluorodeoxyglucose positron emission tomography/computed tomography combined with computed tomography angiography in large-vessel vasculitis

Abstract OBJECTIVES: The objectives of this study were to investigate the clinical application of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG-PET/CT) combined with CT angiography (CTA) fusion images at diagnosis and assessment in large-vessel vasculitis (LVV). MATERIALS AND METHODS: Forty-six patients with LVV who underwent both 18F-FDG-PET/CT and CTA procedures were studied in the Second Hospital of Harbin Medical University from September 2019 to June 2022, and the clinical disease activity of patients was judged by the Physician Global Assessment. Clinical data, acute-phase reactants (APRs), and imaging data were collected. Meanwhile, the APRS must be obtained within 1 week of 18F-FDG-PET/CT. 18F-FDG-PET/CT was primarily used to evaluate LVV activity, while CTA was primarily used to observe morphological changes in arteries, including arterial wall thickening, narrowing, and corresponding complications. PET/CT images were evaluated by two nuclear medicine physicians, both of them unaware of the patients’ laboratory tests and clinical signs. Two nuclear medicine specialists evaluated the PET/CT images and PET/CTA images, who were blinded to the patients’ information. The concordance of two physicians in the LVV visual grading scale was studied by calculating the Cohen’s kappa index (k) which evaluates the power of concordance. The paired t-test was used to analyze the differences between PET/CTA images and PET/CT images. RESULTS: The sensitivity and specificity of the semi-quantitative analysis to assess LVV activity was 94.1% and 93.1%, respectively, when a cutoff of the mean SUVmax/SUVmeanliver of 1.15. It was found that the images obtained after delayed phase were clearer and the contrast between the arterial wall and the lumen was higher in 19 patients. We also concluded that PET/CTA examinations were able to detect more lesion sites compared to PET/CT examinations in 28 patients (P &lt; 0.001), especially for patients with long-term treatment, and the interpretation of PET/CTA images took less time than PET/CT images(P &lt; 0.001), ultimately achieving a shorter time, more comprehensive and accurate interpretation. CONCLUSION: Although 18F-FDG-PET/CT can assess the activity of LVV, it is poor at observing morphological changes in arteries. The use of 18F-FDG-PET/CTA imaging scans in LVV can accurately assess disease activity while at the same time providing a comprehensive, accurate, and efficient determination of disease severity, allowing patients to receive comprehensive diagnostic information from PET/CTA examination.

Developing Topics.

Both 11C-Pittsburgh compound-B (PiB) and 18F-Flutemetamol (FMT) have off-target white matter (WM) signal that increases with age, but WM uptake is stronger with FMT than PiB. Although their WM patterns are comparably associated with age, the difference between them may impact visual and quantitative assessments of cortical amyloid-β uptake. Our objective was to determine whether PiB PET and FMT PET visual assessments agree with quantitative cortical amyloid-β evaluations. A cohort of cognitively unimpaired (CU) younger adults with median (range) of 39 (30, 48) years (N = 30), CU older adults with age of 67 (61, 83) years (N = 30) and older adults with AD dementia with age of 67 (54-84) years (N = 23) underwent MRI, PiB PET and FMT PET. PiB-PET and FMT PET scans were evaluated visually by two nuclear medicine specialists blinded to participant information. Disagreements were reconciled with a second, joint round of visual reads. Readers applied standard visual assessment criteria using the absence of regional gray matter (GM) and WM contrast as an indication of a positive scan. The global cortical PiB standard uptake value ratio (SUVr) was obtained referencing to cerebellar crus uptake and converted to centiloid values. Participants were classified as PiB positive/negative using a centiloid cut-off of 22. PiB and FMT visual positivity agreed with quantitative positivity on PiB-based centiloid values in 69/83 for PiB and 78/83 for FMT. There were 10 disagreements with PiB, 1 disagreement with FMT and 4 disagreements with both. Few disagreements occurred near the centiloid threshold. Interestingly, all disagreements between visual reads (amyloid-β positive) and centiloid (amyloid-β negative) in the CU younger were with PiB. FMT disagreements were always in the CU older and AD groups. Disagreements between amyloid-β positivity on visual reads and quantitative measurements (centiloid) may depend on age and tracer. PiB WM uptake is lower than FMT WM uptake, which may lead to reduced contrast between GM and WM (part of the standard criteria for visual reads), especially in younger ages. In contrast, WM uptake increases at older ages, and increased WM signal may bleed more into cortical regions, hiding subtle, near-threshold cortical uptake, especially with FMT.

Reproducibility and Accuracy of the PRIMARY Score on PSMA PET and of PI-RADS on Multiparametric MRI for Prostate Cancer Diagnosis Within a Real-World Database.

The PRIMARY score is a 5-category scale developed to identify clinically significant intraprostate malignancy (csPCa) on 68Ga-prostate-specific membrane antigen (PSMA)-11 PET/CT (68Ga-PSMA PET) using a combination of anatomic site, pattern, and intensity. Developed within the PRIMARY trial, the score requires evaluation in external datasets. This study aimed to assess the reproducibility and diagnostic accuracy of the PRIMARY score in a cohort of patients who underwent multiparametric MRI (mpMRI) and 68Ga-PSMA PET before prostate biopsy for the diagnosis of prostate cancer. Methods: In total, data from 242 men who had undergone 68Ga-PSMA PET and mpMRI before transperineal prostate biopsy were available for this ethics-approved retrospective study. 68Ga-PSMA PET and mpMRI data were centrally collated in a cloud-based deidentified image database. Six experienced prostate-focused nuclear medicine specialists were trained (1 h) in applying the PRIMARY score with 30 sample images. Six radiologists experienced in prostate mpMRI read images as per the Prostate Imaging-Reporting and Data System (PI-RADS), version 2.1. All images were read (with masking of clinical information) at least twice, with discordant findings sent to a masked third (or fourth) reader as necessary. Cohen κ was determined for both imaging scales as 5 categories and then collapsed to binary (negative and positive) categories (score 1 or 2 vs. 3, 4, or 5). Diagnostic performance parameters were calculated, with an International Society of Urological Pathology grade group of at least 2 (csPCa) on biopsy defined as the gold standard. Combined-imaging-positive results were defined as any PI-RADS score of 4 or 5 or as a PI-RADS score of 1-3 with a PRIMARY score of 3-5. Results: In total, 227 patients with histopathology, 68Ga-PSMA PET, and mpMRI imaging before prostate biopsy were included; 33% had no csPCa, and 67% had csPCa. Overall interrater reliability was higher for the PRIMARY scale (κ = 0.70) than for PI-RADS (κ = 0.58) when assessed as a binary category (benign vs. malignant). This was similar for all 5 categories (κ = 0.65 vs. 0.48). Diagnostic performance to detect csPCa was comparable between PSMA PET and mpMRI (sensitivity, 86% vs. 89%; specificity, 76% vs. 74%; positive predictive value, 88% vs. 88%; negative predictive value, 72% vs. 76%). Using combined imaging, sensitivity was 94%, specificity was 68%, positive predictive value was 86%, and negative predictive value was 85%. Conclusion: The PRIMARY score applied by first-user nuclear medicine specialists showed substantial interrater reproducibility, exceeding that of PI-RADS applied by mpMRI-experienced radiologists. Diagnostic performance was similar between the 2 modalities. The PRIMARY score should be considered when interpreting intraprostatic PSMA PET images.

Detección de la infiltración de la cadena mamaria interna en pacientes con cáncer de mama mediante PET/RM con 18F-FDG y sus implicaciones terapéuticas

ObjectiveTo evaluate the detection rate and therapeutic implication of the infiltration of the internal mammary chain (IMCI) by [18F]FDG PET/MRI for staging of patients with breast cancer. MethodsProspective study including 41 women with breast cancer (stage ≥IIB) staged by [18F]FDG PET/MR. Two-phase exam: breast imaging (prone), whole-body (supine). TNM stage assessed by peer consensus with Nuclear Medicine and Radiology specialists. Study of the afferent vessel (AV) to IMC by breast MRI. IMCI was correlated with age, AV-IMC, T stage, breast quadrants, axillary and distant infiltration. Therapeutic re-evaluation by a multidisciplinary committee. ResultsIMCI detection rate of 34% (14/41), with 8/14 patients under 55 years of age. All 14 patients with IMCI showed AV-IMC, 6 of them (43.9%) without VA-axillary. Of 27/41 patients without IMCI, in 13 (48.1%) only AV-axillary was found, in the remaining 14 (51.9%), AV-axillary and AV-IMC was found. In 57% (8/14) tumours were multicentric and 42% (6/14) focal, in inner quadrants in 4/6 (66.7%). In 1/14 patient (7.1%) only IMCI was found, in 9/14 (64.3%) axillary and IMC, in 4/14 patients (28.6%) distant lesions were detected. Committee re-evaluation: no further treatment in 27/41 patients (65.8%), thoracic radiotherapy in 10/41 patients (24.4%), systemic therapy in 4/41 patients (9.7%). ConclusionOur detection rate of IMCI in breast cancer staging by [18F]FDG PET/MR was 34%. Related factors were age, multicentric tumours, inner quadrants, detection of AV-IMC, NM staging.The evidence of IMCI allowed tailored therapy, with thoracic radiotherapy implementation in 24.4% of patients.

IMPLEMENTASI INDONESIAN DIAGNOSTIC REFERENCE LEVEL (I-DRL) PADA PELAYANAN DIAGNOSTIK IN VIVO KEDOKTERAN NUKLIR DI RSUP DR. SARDJITO TAHUN 2022-2023

The Indonesian Diagnostic Reference Level (I-DRL) value in nuclear medicine was only published in November 2022 by the Nuclear Energy Regulatory Agency (BAPETEN). Implementing I-DRL in in-vivo diagnostic services in nuclear medicine at Sardjito Hospital, which has been running so far, needs ongoing evaluation to help realize an increase in the ratio of benefits to risks of radiation to patients. This research aims to apply I-DRL nuclear medicine at Dr. Sardjito Hospital while still applying the principles of optimizing medical exposure. Optimization focuses on maintaining guaranteed image quality, namely images that are readable or not readable by nuclear medicine specialists, while still implementing radiation protection against medical exposure. The research is a retrospective descriptive method from bone scan patient data from 2022-2023. The selection of 299 bone scan data was based on the most frequently performed examinations. The bone scan imaging tool used was a GE brand single-photon emission computed tomography (SPECT-CT) gamma camera type NM/CT 870 DR. Image processing uses a comparison of region of interest (ROI) values from the target and background on the femur bone using Xeleris software. Based on the image analysis results, the target and background's lowest, average, and highest comparison values were respectively 1.15, 2.1, and 3.75. Spearman statistical testing was also carried out between the dose per Body Mass Index (BMI) and the target/background value ratio, obtaining an R-value of -0.046, which means the two variables have a weak relationship. This research provides information that I-DRL Bone scan can be implemented without affecting the image quality results. Implementing I-DRL is a form of optimizing radiation protection for patients, preventing unnecessary radiation exposure, and ensuring the quality of nuclear medicine services will improve in the future. Keywords: I-DRL, in vivo diagnostics, optimization, radiation protection, bone scan.

Detection of internal mammary chain infiltration in breast cancer patients by [18F]FDG PET/MRI. Therapy implications

ObjectiveTo evaluate the detection rate and therapeutic implication of the infiltration of the internal mammary chain (IMCI) by [18F]FDG PET/MRI for staging of patients with breast cancer. MethodsProspective study including 41 women with breast cancer (stage ≥ IIB) staged by [18F]FDG PET/MR. Two-phase exam: breast imaging (prone), whole-body (supine).TNM stage assessed by peer consensus with Nuclear Medicine and Radiology specialists. Study of the afferent vessel (AV) to IMC by breast MRI. IMCI was correlated with age, AV-IMC, T stage, breast quadrants, axillary and distant infiltration.Therapeutic re-evaluation by a multidisciplinary committee. ResultsIMCI detection rate of 34% (14/41), with 8/14 patients under 55 years of age. All 14 patients with IMCI showed AV-IMC, 6 of them (43.9%) without VA-axillary. Of 27/41 patients without IMCI, in 13 (48.1%) only AV-axillary was found, in the remaining 14 (51.9%), AV-axillary and AV-IMC was found.In 57% (8/14) tumours were multicentric and 42% (6/14) focal, in inner quadrants in 4/6 (66.7%).In 1/14 patient (7.1%) only IMCI was found, in 9/14 (64.3%) axillary and IMC, in 4/14 patients (28.6%) distant lesions were detected.Committee re-evaluation: no further treatment in 27/41 patients (65.8%), thoracic radiotherapy in 10/41 patients (24.4%), systemic therapy in 4/41 patients (9.7%). ConclusionOur detection rate of IMCI in breast cancer staging by [18F]FDG PET/MR was 34%.Related factors were age, multicentric tumours, inner quadrants, detection of AV-IMC, NM staging.The evidence of IMCI allowed tailored therapy, with thoracic radiotherapy implementation in 24.4% of patients.

Performance Analysis of Six Semi-Automated Tumour Delineation Methods on [18F] Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography (FDG PET/CT) in Patients with Head and Neck Cancer.

Background. Head and neck cancer (HNC) is the seventh most common neoplastic disorder at the global level. Contouring HNC lesions on [18F] Fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) scans plays a fundamental role for diagnosis, risk assessment, radiotherapy planning and post-treatment evaluation. However, manual contouring is a lengthy and tedious procedure which requires significant effort from the clinician. Methods. We evaluated the performance of six hand-crafted, training-free methods (four threshold-based, two algorithm-based) for the semi-automated delineation of HNC lesions on FDG PET/CT. This study was carried out on a single-centre population of n=103 subjects, and the standard of reference was manual segmentation generated by nuclear medicine specialists. Figures of merit were the Sørensen-Dice coefficient (DSC) and relative volume difference (RVD). Results. Median DSC ranged between 0.595 and 0.792, median RVD between -22.0% and 87.4%. Click and draw and Nestle's methods achieved the best segmentation accuracy (median DSC, respectively, 0.792 ± 0.178 and 0.762 ± 0.107; median RVD, respectively, -21.6% ± 1270.8% and -32.7% ± 40.0%) and outperformed the other methods by a significant margin. Nestle's method also resulted in a lower dispersion of the data, hence showing stronger inter-patient stability. The accuracy of the two best methods was in agreement with the most recent state-of-the art results. Conclusions. Semi-automated PET delineation methods show potential to assist clinicians in the segmentation of HNC lesions on FDG PET/CT images, although manual refinement may sometimes be needed to obtain clinically acceptable ROIs.

PARATHYROIDECTOMY IN PATIENTS WITH HYPERPARATHYROIDISM

Aim: The aim of this study was to analyze all the factors (disease symptoms, sinthigraphic findings, biochemical parameters) that occur in patients with hyperparathyroidism, and since hyperparathyroidism itself is a common endocrine disorder. Methods: We analyzed 79 patients with primary, secondary, and tertiary hyperparathyroidism, who underwent surgery. We analyzed mean of age, male: female ratio, representation of different forms of hyperparathyroidism. In our study, we examined the indications for examination and surgery, as well as the most common symptoms and comorbidities. For localization PTG, scintigraphy was performed by a nuclear medicine specialist (at the Clinic of Radiology and Nuclear Medicine) preoperatively. Preoperative values of calcium (Ca), phosphorus (P), and parathyroid hormone (PTH) were determined in all patients, and the same values were measured postoperatively. We also analyzed correlation of dialysis length and parathyroid gland hyperplasia in patients with secondary hyperparathyroidism. Results: In our study mean of years was 51.13 ± 11.83 and most of the respondents were female. The most common operation was subtotal parathyroidectomy. The most common indication for examination of parathyroid glands (PTG) was renal failure. The most common comorbidity was arterial hypertension, which was found in 43 (53.2%) subjects, and the rarest gastrointestinal diseases and pancreatitis, in 1 (1.3%) patients. Scintigraphy showed an equal representation of enlarged lower parathyroid glands (both right and left). The mean values determined preoperatively for PTH were 796.24 pg/ml, Ca 2.58 mmol / l and P 1.35 mmol / l. The mean postoperative values for PTH were 222.33 pg/ml, Ca 2.06 mmol/l and P 1.17 mmol/l. We also showed that was a large correlation between dialysis length and hyperplasia. Conclusion: Hyperparathyroidism is a common endocrine disease, carrying potential complications of many organic systems. In most cases, regardless of the form (primary, secondary, or tertiary), it ultimately requires surgical treatment. For this reason, the clinical picture must be well known, the necessary preoperative diagnostic methods (which are complex), all with the aim of better effect of treatment of such patients.

Designing a Marketing Strategy for Samarium 153 ethylenediaminetetramethylene phosphonic acid (Sm 153-EDTMP) for Palliative Treatment of Cancer that Spreads to The Bones

This research is proposed to identify marketing strategic of Samarium ethylenediaminetetramethylene phosphonic acid (Sm 153-EDTMP) that is used for palliative treatment of bone metastasis towards utilization policy by the Nuclear Medicine Doctors. The data is obtained from the questionnaire that were spread out to Nuclear Medicine Doctors in a number of Hospital in Indonesia as respondents. The respondents were 35 of Nuclear Medicine Doctors. This number represents 80 % of Nuclear Medicine Doctors population in Indonesia. The research methodology is accomplished by descriptive explorative analysis. The results are: (1) dose, side effect of Sm 153-EDTMP that is more tolerating than morphine, (2) according to the local product promotion, Sm 153-EDTMP is able to be delivered more effectively to the user through detailing, symposium, internet (3) the price of the local product of Sm 153-EDTMP that is way more cheaper than morphine. By paying attention to marketing strategies through product advantages, promotional forms and prices SM 153-EDTMP shows that these products can be used by Nuclear Medicine specialists (SpKN) as a palliative treatment for cancer that spreads to the bones.