Utility of Lung Perfusion SPECT/CT in Detection of Pulmonary Thromboembolic Disease: Outcome Analysis / 대한핵의학회잡지

Purpose@#To evaluate the clinical outcome of Q-SPECT/CT in pulmonary thromboembolic disease. @*Methods@#From Jan 2020 to Jan 2021, 30 consecutive patients (M:F = 8:22; median age = 52 year (21–89)) suspected of having acute pulmonary embolism (PE) or chronic thromboembolic pulmonary hypertension (CTEPH) were referred for non-contrasted Q-SPECT/CT. All patients were COVID-19 PCR negative. MSKCC Q-SPECT/CT and/or PISAPED criteria were used to determine the presence of thromboembolic disease in Q-SPECT/CT. Final diagnosis was made based on composite reference standards that included at least 2-month clinical cardiorespiratory assessment and follow-up imaging. @*Results@#Q-SPECT/CT was positive in 19 patients: indeterminate in 1 and 10 were negative. Three false positive cases were observed during follow-up. Of the remaining 16 true positives, all patients’ cardiorespiratory symptom were improved or stabilised after treatment with anticoagulants. The overall sensitivity, specificity, PPV, NPV and accuracy of Q-SPECT/CT were 100% (95% CI, 79.41–100%), 78.57% (95% CI, 49.20–95.34%), 84.21% (95% CI, 66.41–93.57%), 100% and 90.00% (95% CI, 73.47–97.89%) respectively. @*Conclusions@#In the current COVID-19 pandemic, Q-SPECT/CT can be an alternative modality to detect pulmonary thromboembolic disease. Normal Q-SPECT/CT excludes pulmonary thromboembolic disease with high degree of certainty. However, false positive has been observed.

Extended Whole‑body Ga‑68 DOTATATE PET‑CT in evaluating Tumour‑Induced Osteomalacia: Case report and review of literature / 대한핵의학회잡지

Tumour-induced osteomalacia is a rare paraneoplastic syndrome that manifests as chronic hypophosphataemia, non-specific bone pain and muscle weakness. It is generally caused by phosphaturic mesenchymal tumour (PMT), which is uncommonly associated with synchronous tumours. However, diagnosis is often delayed for several years due to the rarity, indolent growing nature and non-specific symptoms of the disease, often resulting in an overlook by clinicians during assessments. The patient initially presented with hypophosphataemia and generalised skeletal pain with multiple atraumatic fractures. Blood tests revealed serum calcium levels at the upper limit and extremely low inorganic phosphate levels. Herein, we report a case where two synchronous PMTs from two different sites were detected by ‘extended’ whole-body Ga-68 DOTATATE PET-CT, leading to remission of the disease after complete surgical removal. Early detection and diagnosis of PMT neoplasm is crucial, as complete surgical resection of this tumour is the only definitive treatment currently known. Upon excision, this curable disease will result in complete resolution of symptoms and blood parameters, leading to remission of the disease which significantly improves the patient’s quality of life. PMT often over-expresses somatostatin receptors (SSTR), predominantly subtype 2A, and Ga-68 DOTATATE PET-CT is a selective SSTR imaging that targets this characteristic over-expression in these tumours. The high diagnostic accuracy of Ga-68 DOTATATE PET-CT should be the primary imaging modality for full evaluation of this disease.

Application of 18 F-FDG PET-CT in the management of pulmonary nodule and mass – a pictorial review

@#Background: Lung cancer is one of the leading causes of cancer-related mortality worldwide. Pulmonary nodules are commonly encountered in clinical practice because of the recent implementation of low-dose CT lung screening programme, incidental finding on cardiac CT or CT for nonthoracic related disease. 18 F-FDG PET-CT plays an important role in the management of pulmonary nodules. Methods: In this pictorial review, we present six different scenarios of using 18 F-FDG PET-CT in the management of suspicious pulmonary nodule or mass. The advantages and limitations of 18 F-FDG PET-CT and Herder model are discussed. Results: 18 F-FDG PET-CT with risk assessment using Herder model provides added value in characterising indeterminate pulmonary nodules. Besides, 18 F-FDG PET-CT is valuable to guide the site of biopsy and provide accurate staging of lung cancer. Conclusion: To further improve its diagnostic accuracy, careful history taking, and CT morphological evaluation should be taken into consideration when interpreting 18FFDG PET-CT findings in patients with these nodules.

Impact of ⁶⁸Ga-DOTA-Peptide PET/CT on the Management of Gastrointestinal Neuroendocrine Tumour (GI-NET): Malaysian National Referral Centre Experience / 대한핵의학회잡지

PURPOSE@#The National Cancer Institute is the only referral centre in Malaysia that provides ⁶⁸Ga-DOTA-peptide imaging. The purpose of this study is to determine the impact of ⁶⁸Ga-DOTA-peptide PET/CT on the management of gastrointestinal neuroendocrine tumours (GI-NET).@*MATERIALS AND METHODS@#A cross-sectional study was performed to review the impact of ⁶⁸Ga-DOTA-peptide (⁶⁸Ga-DOTATATE or ⁶⁸Ga-DOTATOC) PET/CT on patients with biopsy-proven GI-NET between January 2011 and December 2015. Suspected NET was excluded. Demographic data, tumoral characteristics, change of disease stage, pre-PET intended management and post-PET management were evaluated.@*RESULTS@#Over a 5-year period, 82 studies of ⁶⁸Ga-DOTA-peptide PET/CT were performed on 44 GI-NET patients. The most common primary site was the rectum (50.0%) followed by the small bowel, stomach and colon. Using WHO 2010 grading, 40.9%of patients had low-grade (G1) tumour, 22.7% intermediate (G2) and 4.5% high (G3). Of ten patients scheduled for pre-operative staging, ⁶⁸Ga-DOTA-peptide PET/CT only led to therapeutic change in three patients. Furthermore, false-negative results of ⁶⁸Ga-DOTA-peptide PET/CT were reported in one patient after surgical confirmation. However, therapeutic changes were seen in 20/36 patients (55.6%) scheduled for post-surgical restaging or assessment of somatostatin analogue (SSA) eligibility. When ⁶⁸Ga-DOTApeptide PET/CT was used for monitoring disease progress during systemic treatment (sandostatin, chemotherapy, everolimus and PRRT) in metastatic disease, impact on management modification was seen in 19/36 patients (52.8%), of which 84.2% had inter-modality change (switch to everolimus, chemotherapy or PRRT) and 15.8% had intra-modality change (increased SSA dosage).@*CONCLUSIONS@#⁶⁸Ga-DOTA-peptide PET/CT has a significant impact on management decisions in GI-NET patients as it can provide additional information on occult metastasis/equivocal lesions and supply the clinician an opportunity to select patients for targeted therapy.

Impact of ⁶⁸Ga-DOTA-Peptide PET/CT on the Management of Gastrointestinal Neuroendocrine Tumour (GI-NET): Malaysian National Referral Centre Experience / 대한핵의학회잡지

PURPOSE: The National Cancer Institute is the only referral centre in Malaysia that provides ⁶⁸Ga-DOTA-peptide imaging. The purpose of this study is to determine the impact of ⁶⁸Ga-DOTA-peptide PET/CT on the management of gastrointestinal neuroendocrine tumours (GI-NET).MATERIALS AND METHODS: A cross-sectional study was performed to review the impact of ⁶⁸Ga-DOTA-peptide (⁶⁸Ga-DOTATATE or ⁶⁸Ga-DOTATOC) PET/CT on patients with biopsy-proven GI-NET between January 2011 and December 2015. Suspected NET was excluded. Demographic data, tumoral characteristics, change of disease stage, pre-PET intended management and post-PET management were evaluated.RESULTS: Over a 5-year period, 82 studies of ⁶⁸Ga-DOTA-peptide PET/CT were performed on 44 GI-NET patients. The most common primary site was the rectum (50.0%) followed by the small bowel, stomach and colon. Using WHO 2010 grading, 40.9%of patients had low-grade (G1) tumour, 22.7% intermediate (G2) and 4.5% high (G3). Of ten patients scheduled for pre-operative staging, ⁶⁸Ga-DOTA-peptide PET/CT only led to therapeutic change in three patients. Furthermore, false-negative results of ⁶⁸Ga-DOTA-peptide PET/CT were reported in one patient after surgical confirmation. However, therapeutic changes were seen in 20/36 patients (55.6%) scheduled for post-surgical restaging or assessment of somatostatin analogue (SSA) eligibility. When ⁶⁸Ga-DOTApeptide PET/CT was used for monitoring disease progress during systemic treatment (sandostatin, chemotherapy, everolimus and PRRT) in metastatic disease, impact on management modification was seen in 19/36 patients (52.8%), of which 84.2% had inter-modality change (switch to everolimus, chemotherapy or PRRT) and 15.8% had intra-modality change (increased SSA dosage).CONCLUSIONS: ⁶⁸Ga-DOTA-peptide PET/CT has a significant impact on management decisions in GI-NET patients as it can provide additional information on occult metastasis/equivocal lesions and supply the clinician an opportunity to select patients for targeted therapy.

Features of post-radioiodine whole body scan in non-invasive Follicular Thyroid Neoplasm with papillary-like nuclear features (NIFTP)

carcinoma has been reclassified as non-invasive follicularthyroid neoplasm with papillary-like nuclear features (NIFTP)to emphasize the benign nature of this entity. In ourinstitution, we have assessed 455 patients treated withradioiodine ablation for differentiated thyroid carcinoma and20 of them were retrospectively found to fulfill the newNIFTP criteria. There was no evidence of metastasis on postradioiodine whole body scans for NIFTP cases and thesepatients were in remission subsequently. The benignfeatures of these patients’ whole body scans and goodclinical outcome following treatment further support NIFTPas a low risk thyroid neoplasm.