Abstract The aim of this study was to establish facility-specific and provisional multicenter local diagnostic reference levels (LDRLs) for adult ventilation–perfusion (V/Q) single-photon emission computed tomography (SPECT)/computed tomography (CT) examinations in South African nuclear medicine facilities using a structured multicenter approach consistent with international DRL methodology. A retrospective study was conducted between 2021 and 2024 across three South African nuclear medicine facilities. Adult patients (≥18 years) undergoing either 2-day V/Q SPECT/CT or 1-day perfusion-only SPECT/CT were included. Facility median administered activities and CT dose metrics including volume computed tomography dose index (CTDIvol) and dose-length product (DLP) were calculated. Provisional multicenter LDRLs were derived as the 75th percentile of facility median values. Owing to the limited number of participating facilities (n = 3), the resulting values are presented as preliminary multicenter optimization benchmarks rather than nationally representative DRLs. A total of 175 adult studies were analyzed (median age 50 years; interquartile range: 33.0–67.5). One facility performed 2-day V/Q imaging using Technegas and 99mTc-MAA, whereas all three facilities performed 1-day perfusion-only protocols using 99mTc-MAA. For the 2-day V/Q protocol, provisional benchmark values derived from a single participating facility were 500 MBq for ventilation activity, 185 MBq for perfusion activity, 3.9 mGy for CTDIvol, and 142 mGy·cm for DLP. For 1-day perfusion-only studies, the provisional LDRLs were 285 MBq for perfusion activity, 4.6 mGy for CTDIvol, and 172 mGy·cm for DLP. Substantial interfacility variability was observed, particularly for CT dose metrics. This study established the first provisional multicenter LDRLs for adult V/Q SPECT/CT in South Africa. Considerable interfacility variability in CT dose metrics was observed, reflecting differences in scanner technology, exposure-control strategies, protocol implementation, and scan-length selection. The proposed protocol-specific optimization benchmarks, comprising provisional multicenter LDRLs for 1-day perfusion-only imaging and provisional benchmarks for the 2-day V/Q protocol, provide practical guidance for dose harmonization across participating facilities. Elevated administered activities observed for 1-day perfusion-only protocol exceeded internationally recommended activity ranges and therefore represent an important target for protocol optimization. Further multicenter expansion will be required to support the future development of nationally representative diagnostic reference levels for adult V/Q SPECT/CT practice in South Africa.
Abstract Prostate cancer is the second most common cancer in men and a leading cause of cancer-related death worldwide. Accurate staging is essential for effective treatment. The use of gallium-68 (68Ga)-prostate-specific membrane antigen (PSMA) positron emission tomography-computed tomography (PET-CT), a highly sensitive and specific imaging technique, has increased for staging and detecting biochemical recurrence in prostate cancer patients. This retrospective study evaluated 68Ga-PSMA PET-CT scans of 78 patients with histologically confirmed prostate adenocarcinoma acquired between December 2019 and April 2021. Gleason grade group, prostate-specific antigen level, National Comprehensive Cancer Network (NCCN) risk, American Joint Committee on Caner (AJCC) stage, and treatment history were reviewed, with follow-up until December 2024. The lesions were scored visually using the molecular imaging PSMA (miPSMA) score and maximum standardized uptake value (SUVmax) was measured. Data were analyzed in SPSS 27.0 using chi-square, Kruskal–Wallis, and Kaplan–Meier tests, with a p-value of ≤ 0.05 considered significant. The mean age of the patients was 66.5 ± 8.9. 68Ga-PSMA PET-CT altered the management of 48% of patients, upstaging the disease in 79% of these cases by identifying additional metastatic sites. SUVmax had a positive association with miPSMA score (p < 0.05), but not with Gleason grade group, AJCC stage, NCCN risk, or age. At 37-month follow-up, 54% were alive and 13% had died. Exploratory analysis showed that higher miPSMA score was associated with overall poor survival rates. We also detected incidental lesions later diagnosed as second primary cancers in two patients, including renal cell carcinoma and hepatocellular carcinoma. Our institutional experience with 68Ga-PSMA PET-CT showed a major impact on management, altering treatment in nearly half of patients through disease upstaging or downstaging. miPSMA score showed association with SUVmax but not with Gleason grade group, AJCC stage, NCCN risk, or age. Exploratory findings suggest a possible association between higher primary tumor miPSMA scores and poorer survival outcomes.
A 31-year-old man with known polyostotic fibrous dysplasia (FD) presented with progressive right wrist swelling. Imaging with fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) demonstrated multiple FDG-avid skeletal lesions consistent with FD, along with an additional morphologically distinct FDG-avid soft-tissue lesion in the right wrist lacking typical intramedullary characteristics. Although the metabolic activity of this lesion was comparable to other FD lesions, its atypical morphology raised suspicion of a superimposed pathology. Histopathological evaluation confirmed giant cell tumor (GCT) of bone. Subsequent 99mTc-sestamibi scintigraphy demonstrated tracer uptake confined to the wrist lesion, with no uptake in FD lesions, indicating differential tracer behavior. The coexistence of FD and GCT is exceedingly rare and poses a diagnostic challenge, particularly in the setting of overlapping metabolic imaging findings. Here, we present a rare case of concomitant FD with GCT.
Metronidazole is a widely prescribed antibiotic used for treating bacterial and protozoal infections. Neurological complications from metronidazole are rare, but they have been associated with several syndromes, including cerebellar syndrome, encephalopathy, seizures, autonomic neuropathy, optic neuropathy, and peripheral neuropathy.We present the case of a 25-year-old male patient who had a recurrent amoebic liver abscess, received long-term intravenous and oral treatment with metronidazole, and developed cerebellar syndrome and parkinsonism.Electroencephalogram, computed tomography scan, and magnetic resonance imaging of the brain, along with various laboratory tests, revealed no abnormalities.The molecular imaging service performed a dual positron emission tomography imaging with FDG and FDOPA, ruling out neurodegenerative parkinsonism and suggesting a possible pharmacological cause.
Positron emission tomography (PET) myocardial perfusion imaging (MPI) is a highly accurate noninvasive modality for evaluating coronary artery disease due to its excellent sensitivity and specificity, excellent image quality, efficient imaging protocol, and significantly lower radiation exposure. Its ability to absolutely quantify myocardial blood flow (MBF), MBF-R, and left ventricular ejection fraction-reserve also strengthens its diagnostic and prognostic properties and guides physicians about the justification for coronary revascularization. Presence of coronary artery calcification on the CT component indicates atherosclerosis, and its presence with normal PET MPI indicates subclinical nonobstructive coronaries and warrants risk factor medication to avoid future major adverse cardiac events. Metabolic imaging with FDG PET is considered the gold standard for diagnosing hibernating myocardium and helps in the management of sarcoidosis and infection of the cardiovascular system and implanted devices. However, the huge upfront and operational costs are the primary factors for the limited availability of PET MPI.
Background:Dual-tracer positron emission tomography/computed tomography (PET/CT) using [ 18 F]FDG and fibroblast activation protein inhibitor (FAPI) provides complementary metabolic and stromal information in radioiodine-refractory differentiated thyroid carcinoma (DTC). However, response patterns during systemic therapy remain incompletely understood. Case:A 60-year-old male with papillary thyroid carcinoma (pT2 pN1a pM0) underwent total thyroidectomy and bilateral neck dissection. After defaulting from follow-up, he developed diffuse pulmonary and mediastinal metastases. Following one therapeutic dose of 200 mCi (7.4 GBq) [ 131 I], the disease became radioiodine-refractory (thyroglobulin-elevated negative iodine scintigraphy syndrome). Baseline Fluorine-18 Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography ([ 18 F]FDG PET/CT) demonstrated hypermetabolic pulmonary and mediastinal metastases. Gallium-68 fibroblast activation protein inhibitor Positron Emission Tomography/Computed Tomography ([ 68 Ga]Ga-FAPI-04 PET/CT) performed the following day showed corresponding fibroblast activation protein expression without discordant lesions, although there was a low expression profile of [ 68 Ga]Ga-FAPI-04 PET/CT observed at the baseline compared with the [ 18 F]FDG PET/CT. After 10 months of lenvatinib (14 mg once daily), [ 18 F]FDG PET/CT demonstrated stable metabolic disease according to PERCIST 1.0 criteria, whereas [ 68 Ga]Ga-FAPI-04 PET/CT showed marked reduction of FAP expression in mediastinal nodes and several pulmonary nodules. Serum thyroglobulin decreased from 574 ng/mL to 457 ng/mL without anti-thyroglobulin antibody interference. The multidisciplinary team classified the case as stable disease based on persistent FDG avidity. Conclusion:Discordant response patterns between FDG and FAPI PET/CT highlight the complementary biological information provided by dual-tracer imaging. Reduction in stromal FAP expression did not equate to metabolic remission. Combined interpretation may improve response assessment in radioiodine-refractory DTC.
Purpose:Intratumoral heterogeneity is a primary driver of treatment resistance in many malignancies, including esophageal cancer. While Fluorine-18 Fluorodeoxyglucose positron emission tomography/computed tomography (F-18 FDG PET/CT) is a standard tool for staging and response assessment in the esophageal malignancy, the qualitative visual assessment of primary tumor and metastases is limited by interobserver variability. The purpose of this study is to determine if the non-invasive imaging biomarkers on F-18 FDG PET can reliably distinguish the two primary histological subtypes of esophageal malignancy namely squamous cell carcinoma (SCC) and adenocarcinoma (AC). Methods:This is a retrospective study approved by the institutional ethical committee, and conducted in histopathologically proven cases of esophageal malignancy of either squamous cell or AC subtypes, who underwent baseline staging F-18 FDG PET/CT as per the standard guidelines. The metabolic parameters namely tumoral maximum standardized uptake value (SUVmax), total lesional glycolysis (TLG), metabolic tumor volume (MTV) and metabolic ratio of tumor to liver (standardized uptake ratio [SUR]) were calculated and compared between the two histological subtypes using Mann - Whitney U test. A p -value of less than 0.05 was considered statistically significant. Results:Out of 59 patients (M:F = 33:26) included in the study, 40 had squamous cell subtype and 19 had AC. Median age was 57 years (range: 30-83), and the median SUVmax, SUR, MTV, and TLG of AC group was 10.89 g/mL, 3.86, 9.98 mL, and 55.8 g/mL, while that of squamous group was 13.88 g/mL, 5.6, 13.52 mL, and 108.4 g/mL, respectively. There was significant difference noted in the tumoral SUVmax ( p = 0 .043) , SUR ( p = 0 .019 ), and TLG ( p = 0 .032 ) between the two groups, with higher metabolic values observed in the squamous group. MTV ( p = 0 .224 ) between the two groups was insignificant. Conclusion:This study demonstrates that quantitative parameters on F-18 FDG PET are effective non-invasive biomarkers for differentiating the histological subtypes of esophageal malignancy. The squamous cell subtype exhibits significantly higher metabolism and total lesion glycolysis than AC.
Background:68 Ga- and 18 F-labeled prostate-specific membrane antigen (PSMA)-targeted positron emission tomography (PET) agents have advanced prostate cancer (PC) imaging. 64 Cu-SAR-bisPSMA may offer several advantages for imaging of PC over standard-of-care PSMA PET agents due to its sarcophagine chelator, bivalent structure and longer half-life of 64 Cu (12.7h vs. <2h for 68 Ga and 18 F), which may lead to detection of additional and smaller lesions. This study determined the administered activity (AA) of 64 Cu-SAR-bisPSMA required to achieve diagnostic-quality imaging for clinical use. Methods:The PROPELLER trial (CLP03; NCT04839367) enrolled 30 men with untreated, histopathology-confirmed, primary PC with intermediate- to high-risk features. Participants received an intravenous injection of 64 Cu-SAR-bisPSMA at 100, 150, or 200 MBq, followed by whole-body PET/computed tomography 2 to 4 hours post-injection. Images were anonymized, randomized, and reviewed by two blinded central readers using the three-point Image Utility Classification Score. For intra-individual comparisons, a subset of images acquired at 200 MBq were digitally reconstructed to simulate 100 and 150 MBq acquisitions on the same scanner; these were randomized and then evaluated by a blinded reader. They were ranked from best image to worst image and scored with a 4-item, 5-point Likert Image Quality Score (maximum 20 points). Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were also measured. Results:Mean Image Utility Classification Score was the highest in the 200 MBq 64 Cu-SAR-bisPSMA cohort compared with the 100 and 150 MBq cohorts (1.44, 1.17, and 0.92, respectively). For the intra-individual comparisons, images corresponding to 200 MBq were ranked as having the best image quality with a statistically significant difference in image quality ranking between AAs ( p = 0.0025). The mean Image Quality Score was highest at 200 MBq of 64 Cu-SAR-bisPSMA (16.0 ± standard deviation 1.10) versus 150 MBq (12.2 ± 1.17) and 100 MBq (10.3 ± 1.63). Quantitatively, 200 MBq of 64 Cu-SAR-bisPSMA had the greatest SNR in both the liver and prostate and the highest CNR for liver relative to the gluteus muscle. Conclusions:An AA of 200 MBq was identified as the optimal AA for 64 Cu-SAR-bisPSMA PET, yielding improved image quality across both qualitative and quantitative metrics compared with 150 and 100 MBq. These findings support the selection of 200 MBq for clinical studies evaluating 64 Cu-SAR-bisPSMA as an imaging agent for PC. NCT04839367, Registered 2021-04-07.
In metastatic prostate adenocarcinoma, the dual-tracer PET imaging approach with gallium-68 (Ga-68)-prostate-specific membrane antigen (PSMA)-11 positron emission tomography (PET)/computed tomography (CT) and fluorodeoxyglucose (FDG) PET/CT provides valuable insights into the disease's receptor-based and glucose metabolic imaging features. In our case series, we highlight a flip-flop pattern observed on both imaging modalities in metastatic castration-resistant prostate adenocarcinoma cancer (mCRPC) patients with confirmed Tp53 mutations. While skeletal metastases showed both PSMA expression as well as FDG avidity, the lymph nodal and hepatic metastases showed only FDG avidity and no PSMA expression. These contrasting findings suggest that Tp53 mutations may influence tumor biology in mCRPC, potentially altering PET-CT imaging signatures in different organs, with its potential implications for treatment decisions. The presented case series in this communication indicate a possible association between Tp53 mutation and organ-specific molecular imaging heterogeneity in mCRPC patients, highlighting the role of dual-tracer PET in personalized theranostic planning in mCRPC.
Splenic metastases from neuroendocrine tumors (NETs) are a rarely encountered site of metastases. The present case illustrates splenic metastases in the setting of NET of unknown primary (CUP-NETs), wherein (68) Ga-DOTATATE PET/CT (positron emission tomography/computed tomography) demonstrated intense somatostatin receptor (SSTR) expression in the widely metastatic CUP-NETs with hepatic, skeletal, and rare splenic metastases. After (177) Lu-DOTATATE PRRT, post-therapy whole-body planar and SPECT-CT imaging showed significant radiopharmaceutical uptake in the lesions, highlighting theranostic concordance. This case illustrates the value of (1) SSTR-based PET-CT imaging, demonstrating SSTR expressing rare sites of metastasis, making it possible to narrow down the diagnosis relating it to a neuroendocrine etiology in CUP-NETS and (2) SSTR-based imaging and theranostics and molecular targeted endo-radiotherapy in detecting and managing atypical metastatic sites in the setting of CUP-NETs.
Objectives Cardiac sarcoidosis can lead to arrhythmias, heart failure, and sudden cardiac death. Positron emission tomography/computed tomography (PET/CT) is crucial for diagnosis and monitoring, yet data from the Middle East and North Africa (MENA) region remain scarce. This study evaluated the role of PET/CT in diagnosing and managing cardiac sarcoidosis at a tertiary referral center in the Middle East. Materials and Methods This retrospective study included 19 patients with biopsy-proven sarcoidosis who underwent fluorine-(18) fluorodeoxyglucose (FDG) PET/CT for suspected cardiac involvement at a tertiary referral medical center in Lebanon between 2014 and 2024. Complementary imaging with echocardiography, cardiac magnetic resonance imaging, and electrocardiography was also analyzed alongside treatment approaches and follow-up outcomes. Results FDG PET/CT identified cardiac involvement in 12 patients, with diffuse or focal FDG uptake patterns correlating with symptom severity and electrocardiographic abnormalities. These patients exhibited higher rates of arrhythmias, conduction abnormalities, and reduced global longitudinal strain and E/A ratio on echocardiography. Cardiac magnetic resonance imaging demonstrated late gadolinium enhancement in most cases with FDG PET/CT-confirmed cardiac sarcoidosis, supporting the presence of myocardial inflammation. Treatment included corticosteroids, immunosuppressive agents, and device implantation in selected cases. Follow-up FDG PET/CT showed significant reductions in FDG uptake, indicating therapeutic response. Conclusion This study underscores the clinical utility of FDG PET/CT in diagnosing and managing cardiac sarcoidosis, particularly in resource-limited settings like the MENA region. FDG PET/CT enabled early detection, guided treatment decisions, and facilitated monitoring of therapeutic response. These findings highlight the need for broader access to FDG PET/CT imaging in the region to optimize patient outcomes.
Objective This study aimed to assess the diagnostic performance of diuretic-enhanced dual-phase F-18 FDG PET/CT in detecting muscle invasion in bladder cancer (BC) and to evaluate the predictive role of metabolic and volumetric PET parameters. Methods A total of 105 patients (85 males, 20 females; mean age: 67.8 years) with suspected BC underwent F-18 FDG PET/CT for initial staging. Routine and delayed pelvic imaging was performed after intravenous furosemide. Metabolic and volumetric parameters, including SUVmax, SUVmean, metabolic tumor volume (MTV), and total lesion glycolysis (TLG), were measured and correlated with histopathological findings. Statistical analyses consisted of Mann-Whitney U, Kruskal-Wallis, and Receiver operating characteristic (ROC) curve analysis. Results Distant metastases were detected in 30 patients (28.5%), which directly influenced treatment decisions. In the TUR-B cohort (n = 75), F-18 FDG PET/CT demonstrated a sensitivity of 78.0%, specificity of 62.5%, positive predictive value of 88.5%, negative predictive value of 43.5%, and an overall accuracy of 74.7% in differentiating malignant from benign bladder lesions. Among the 59 patients with confirmed malignancy, volumetric parameters correlated with pathological T-stage. Patients with T2 tumors had significantly higher SUVmax, SUVmean, MTV, and TLG values compared with
Purpose:We aimed to investigate the early side effects of recombinant human thyroid-stimulating hormone (rhTSH)-aided radioactive iodine (RAI) administration in an unselected cohort of patients with differentiated thyroid cancer (DTC) in the real-world setting. Methods:During follow-up (at 6 weeks, 6 months, and 12 months post-RAI) of patients with DTC who received rhTSH-aided RAI, we used a standardized questionnaire to collect patient-reported side effects of RAI. We investigated the factors that impact the occurrence of RAI-associated side effects. Results:A total of 111 patients with a female predominance (66.7%) and a mean age of 51.1 ± 16.0 years were included, including 13 patients (11.7%) who had previously received RAI. The predominant tumor histology was papillary thyroid cancer, with 91.0% of patients having stage I/II disease. At 6-week follow-up, loss of taste/smell, nausea, salivary gland pain or swelling, dry mouth, and neck pain were reported by 45.9, 37.8, 30.6, 36.9, and 20.7% of patients, respectively. In most patients, these side effects lasted for less than 1 week. At 6-month post-RAI, 13 patients reported lingering RAI-associated side effects, including 4 and 3 patients who reported dry mouth and dry eyes, respectively. A 12-month post-RAI, one patient each reported dry eyes, watery eyes, and fatigue as RAI side effects. Women were at higher risk of neck pain, while young patients were more likely to experience nausea ( p < 0.05). Conclusion:rhTSH-aided RAI administration in DTC patients is associated with tolerable side effects, most of which resolved within weeks of treatment.
Background:Gallbladder carcinoma (GBC) is an aggressive malignancy with a poor prognosis, often diagnosed at a locally advanced stage. Accurate risk stratification is crucial for optimizing treatment, yet conventional imaging and staging systems have limitations. This study aimed to evaluate the prognostic value of metabolic and volumetric parameters from 18 F-fluorodeoxyglucose positron emission tomography/computed tomography ( 18 F-FDG PET/CT) in patients with locally advanced GBC. Methods:This retrospective study included 32 patients with biopsy-confirmed, locally advanced GBC who underwent baseline 18 F-FDG PET/CT. The standard uptake values (SUVmax, SUVmean), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were measured for both primary tumors and nodal metastases. A univariate Cox proportional hazards model was used to assess the association between these volumetric metabolic PET parameters and progression-free survival (PFS) and overall survival (OS). The multivariate Cox model was used to test the independence of significant univariate prognostic factors. Results:In the univariate analysis of volumetric metabolic PET parameters of primary tumors, higher pSUVmean (hazard ratio [HR]: 1.39, p = 0.04), pTLG2.5 (per 100 units; HR: 1.01, p = 0.02), pMTV40 (HR: 1.00, p = 0.02), and pTLG40 (per 100 units; HR: 1.09, p = 0.01) were all significantly associated with worse OS. Similar significant associations were found for PFS. Notably, the conventional metric of pSUVmax was not a significant predictor of either PFS ( p = 0.11) or OS ( p = 0.25). On multivariate analysis, pTLG40 remained an independent predictor of survival. Furthermore, none of the volumetric metabolic PET parameters derived from nodal metastases showed a significant association with survival outcomes. Conclusion:Volumetric metabolic PET parameters, particularly TLG and MTV, which reflect the total metabolic burden of the primary tumor, may offer greater prognostic utility in locally advanced GBC compared with the conventional SUVmax. These parameters should be considered for integration into prognostic models to enhance patient risk stratification and guide personalized therapeutic strategies.
Lipedema is a chronic and underrecognized adipose tissue disorder in women, often misdiagnosed as obesity or lymphedema. Diagnosis is challenging due to overlapping clinical features and the lack of standardized imaging criteria. We report a 50-year-old postmenopausal woman, known hypothyroid on thyroxine and currently euthyroid, presenting with a 6-year history of progressive, symmetrical bilateral lower-limb swelling, predominantly involving the thighs and legs with sparing the feet. Body mass index was 37.8 kg/m (2) (Class II obesity). Lower-limb Doppler ultrasonography excluded arterial or venous obstruction, and filarial serology was negative. Crucially, lymphoscintigraphy, a cost-effective and readily available nuclear medicine tool, demonstrated normal lymphatic drainage, excluding lymphedema and prompting whole-body dual-energy X-ray absorptiometry (DEXA) for further assessment. Whole-body DEXA revealed obesity with disproportionately increased and symmetrical lower limb fat, elevated fat mass index (16.7 kg/m (2) ), and near-equal trunk-to-leg fat distribution, suggestive of a possible lipedema phenotype (Stage II). Magnetic resonance imaging showed extensive symmetrical fat signal intensity in the subcutaneous layer, supporting the DEXA findings. This case emphasizes the sequential role of nuclear medicine techniques-lymphoscintigraphy for functional lymphatic assessment and DEXA for quantitative body composition analysis-in the accurate diagnosis of lipedema, in an obese postmenopausal woman.
Phosphaturic mesenchymal tumor (PMT) is an uncommon neoplasm and the leading cause of tumor-induced osteomalacia (TIO). We report a 55-year-old woman with a 2-year history of progressive hip pain and hypophosphatemia. Laboratory findings demonstrated renal phosphate wasting. Conventional imaging revealed a small soft-tissue nodule in the right thigh, and (18) F-AlF-NOTA-octreotide (18F-OC) PET/CT (positron emission tomography/computed tomography) showed intense radiotracer uptake, accurately localizing the culprit lesion. Surgical excision confirmed a PMT, and serum phosphate levels normalized postoperatively with resolution of symptoms. This case highlights the diagnostic value of (18) F-OC PET/CT in detecting small PMTs and underscores the importance of considering TIO in patients with persistent hypophosphatemia and unexplained musculoskeletal symptoms.
Subcutaneous panniculitis-like T cell lymphoma is described in the literature. However, subcutaneous panniculitis in B-cell lymphoma is extremely rare and, to the best of our knowledge, has not been described in the literature. Differentiating between B-cell and T-cell lymphoma is important in the management of a patient. F-18 FDG PET/CT aids in diagnosis and staging, and also guides appropriate sites for biopsy in this rare clinical conundrum.
A 67-year-old woman presented with recurrent pancreatitis and biochemical evidence of primary hyperparathyroidism, including elevated parathyroid hormone, hypercalcemia, and low vitamin D levels. Neck ultrasonography and technetium-99m sestamibi single-photon emission computed tomography/computed tomography (CT) concordantly localized a left inferior parathyroid lesion. Gallium-68 (Ga-68) Trivehexin positron emission tomography (PET)/CT was performed as an exploratory molecular imaging modality and demonstrated intense tracer uptake corresponding to the suspected adenoma, which was subsequently confirmed on histopathology following focused left inferior parathyroidectomy. In addition, whole-body imaging revealed multiple incidental endocrine lesions, including a pituitary microadenoma (corroborated on magnetic resonance imaging, pituitary protocol), a right parotid adenoma (confirmed on histopathology as pleomorphic adenoma), and a lesion in the submental region, clinically suggestive of lingual thyroid without functional confirmation. There was no clinical, biochemical, or scan evidence suggestive of a syndromic association such as multiple endocrine neoplasia. This case highlights the potential complementary role of Ga-68 Trivehexin PET/CT in providing whole-body molecular imaging and identifying additional incidental findings beyond conventional localization modalities, which may warrant further evaluation in selected cases.
[F-18]FDG-PET/CT (F-18-fluorodeoxyglucose positron emission tomography/computed tomography) plays a crucial role in comprehensive oncologic staging and management of lung carcinoma. Although vertebral involvement is common in advanced malignancy, direct intraspinal extension with resultant neurological complications is uncommon but a clinically significant entity and may necessitate urgent intervention. We present a case of biopsy-proven poorly differentiated lung carcinoma in a 74-year-old male in whom [F-18]FDG-PET/CT demonstrated an intensely FDG-avid paraspinal lung mass with chest wall invasion, vertebral destruction, and intraspinal extension causing spinal cord compression. The study additionally revealed a markedly distended urinary bladder consistent with the patient's clinical symptoms of neurogenic bladder secondary to spinal involvement, along with an associated large pneumothorax. This case highlights the value of [F-18]FDG-PET/CT in comprehensive disease assessment and in detecting life-threatening neurological complications beyond routine staging. An FDG-avid psoas collection raised the possibility of an infective/inflammatory mimic, emphasizing interpretive pitfalls of FDG uptake in infection and inflammation.
