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Skin metastases are rare from systemic malignancy, and incidence reported is between 0.7% and 9% in various malignancies and usually occur in advanced stage. Here, we report three cases, one each of carcinoma esophagus, carcinoma breast, and carcinoma lung, where patients presented with metastatic cutaneous lesions and positron-emission tomography-computed tomography (PET-CT) scan whole body helped in localizing the primary site. Whole-body fluorodeoxyglucose PET-CT scan helps in scanning whole body at once and detect occult primary and metastatic sites. [ABSTRACT FROM AUTHOR]

Phase analysis using gated single-photon emission computed tomography myocardial perfusion imaging (SPECT-MPI) is a relatively new tool for the assessment of ventricular synchrony. Hypertension, diabetes, renal diseases, and dyslipidemia may affect the phase parameters though their impact is not well understood. The present study aimed to evaluate the incidence of the left ventricular mechanical dyssynchrony (LVMD) in end-stage renal disease (ESRD) patients with normal gated SPECT-MPI and QRS duration (<120 ms) on electrocardiogram. Data of 129 patients (86 males) referred for gated SPECT-MPI for their pretransplant evaluation with normal gated stress SPECT-MPI (SSS <3 and ejection fraction ≥50%) were included in the study analysis. Documented clinical history along with confounding factors such as hypertension, dyslipidemia, smoking, and alcoholism were evaluated. Left ventricle functional (end-diastolic, end-systolic, and LV myocardial volume) and phase parameters (phase standard deviation [PSD], phase bandwidth [PBW] and entropy) were calculated using the QPS-QGS program. LVMD was noted in 36 (28%) of ESRD patients with normal QRS duration and gated SPECT-MPI. The mean attenuated corrected LV myocardial volume, ejection fraction, mean PSD, and PBW values were 84.3 ± 38.1 ml, 65.3 ± 13.5%, 9.8° ± 3.9°, and 61.4° ± 24.7°, respectively. The LV myocardial volume shows statistically significant correlation with the phase parameters (r = 0.31–0.47; P < 0.001). LVMD is present in a significant number of ESRD patients, and its extent is more with increase in LV myocardial volume. It may have an additional role in risk-stratification for cardiovascular disease in ESRD patients. [ABSTRACT FROM AUTHOR]

Malignant melanoma is a highly aggressive tumor and surgical resection is the primary treatment. However, the chances of recurrence are quite high despite complete resection. The aim of study was to evaluate the18F-fluorodeoxyglucose(18F-FDG) positron emission tomography–computed tomography (PET/CT) in detection of recurrent melanoma after curative surgery and its prognostic value. Fifty-four melanoma patients (32 women) with prior primary lesion resection were evaluated with18F-FDG PET/CT for clinically suspicious recurrent disease. The diagnostic accuracy of 18F-FDG PET/CT (visual interpretation as well as semi-quantitative parameter) was determined on the basis of subsequent imaging and clinical follow-up. Melanoma-specific survival and risk of progression (hazard ratio [HR]) were assessed using Kaplan–Meier method and Cox regression analysis.18F-FDG PET/CT detected recurrent diseases in 36 (66%) patients including distant metastases in 13 patients and second synchronous malignancy in 2 patients. Overall, the sensitivity, specificity, positive predictive value, and negative predictive value of 18F-FDG PET/CT were 91.2%, 80.0%, 88.6%, and 84.2%, respectively, with area under the curve of 0.86 (95% confidence interval: 0.74–0.97; P < 0.05). Positive18F-FDG PET/CT study was associated with a significantly shorter overall survival than negative study (30.8 ± 4.6 vs. 64.5 ± 6.9 months, P < 0.05). Apart from positive18F-FDG PET/CT scan, maximum standardized uptake value (SUVmax) >2.7 and combination of both were independently associated with an increased risk of disease progression (HR = 7.72, 21.58, and 11.37, respectively; P < 0.05).18F-FDG PET/CT showed enhanced diagnostic performance in patients with suspicious recurrent malignant melanoma leading to appropriate management. FDG positivity along with SUVmax >2.7 provides important prognostic value in predicting the survival outcomes and assessing the risk of disease progression. [ABSTRACT FROM AUTHOR]

68Ga-labeled prostate-specific membrane antigen (PSMA) ligand positron emission tomography/computed tomography imaging (PET/CT) is a rapidly evolving imaging modality for prostate cancer. Many studies have proved its superiority in staging, restaging, and detecting the recurrent prostate cancer. However, case reports describing the incidental tracer uptake in benign and nonprostatic malignancies are also reported in the literature, thus questioning the specificity of the tracer. This pictorial assay illustrates the nonspecific tracer uptake encountered during PSMA PET/CT imaging, knowledge of which can increase the confidence of interpreting physicians and may also open a new path for peptide receptor radionuclide therapy in nonprostatic malignancies. [ABSTRACT FROM AUTHOR]

Background: Phase analysis can be easily performed by different software to assess the left ventricular dyssynchrony from gated single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) with high precision. However, the normal values of histogram bandwidth (HBW) and phase standard deviation (PSD) and their comparison using different programs have not been fully elucidated and actively being evaluated at present. The aim of this study was to determine the phase analysis parameters values and to compare the phase indices of two commonly used programs in a group of patients with normal gated SPECT-MPI. Methods: Phase parameters were retrospectively evaluated in 138 consecutive nondiabetic patients having a normal gated SPECT-MPI using the quantitative gated SPECT (QGS) and Emory Cardiac Toolbox (ECTb) software. HBW, PSD, and phase entropy were calculated separately using both programs. Results: The fair correlation between software programs was observed. HBW and PSD in QGS and ECTb were 26.20 ± 9.7 and 25.46 ± 8.0 (r-value. 56, SEE 6.65) and 6.64 ± 2.5 and 7.65 ± 2.5 (r = 0.54, SEE 2.14), respectively. The value of phase entropy in QGS program was 45.08 ± 6.3. A fair correlation between phase entropy and PSD in QGS was observed (r = 0.44, 95% confidence interval-0.29-0.56). Conclusion: Phase analysis parameters derived from gated SPECT-MPI in patients with normal myocardial perfusion are program dependent and may differ. The results cannot be interchangeably used in the same patients. [ABSTRACT FROM AUTHOR]

The purpose of the study is to find out the overall incidence of superscan among different type of cancers, causes of superscan and its relationship with other parameters such as age, sex, duration of disease, and serum alkaline phosphatase (ALP) levels. This was a retro-prospective study. Records of all previous bone scans and reported patients of superscan were re-evaluated retrospectively. Patients who were diagnosed as having superscan in the preceding 3 years with confirmed histopathological diagnosis were included in the retrospective group. In the prospective group, all the patients who were reported to have superscan appearance over the past 2 years of prospective period were included. Total of 6027 bone scans were examined in a 5-year period and out of which 80 cases were diagnosed as superscan. The overall incidence of superscan in different type of cancers was 1.3% (80/6027). Prostate cancer (46/80) was the most common cause of superscan appearance followed by breast cancer (10/80). Out of 6027 patients referred for bone scan, 307 patients had prostate cancer on histopathological examination. Out of 307 patients with prostate cancer, 46 had superscan appearance. Incidence of superscan in prostate cancer was 14.98% (46/307), and 71.73% (33/46) prostate cancer patients with superscan had Gleason score of 8 and above 8 with mean serum prostate-specific antigen level was 178.42 ng/ml in symptomatic patients and 122 ng/ml in asymptomatic patients. Out of all patients with superscan, 71 patients (88.7%) had elevated serum ALP levels. Overall incidence of superscan in our study was 1.3% in different type of cancer patients, and the most common cause of superscan appearance was prostate cancer. Incidence of superscan appearance in prostatic cancer patients was 14.98%. [ABSTRACT FROM AUTHOR]

Testicular torsion is a common differential diagnosis of acute scrotal pain along with acute epididymo-orchitis, which may lead to testicular non-viability. Doppler ultrasound and testicular scintigraphy are two routinely used modalities for the assessment of testicular viability. However, in some cases, these investigations may prove inadequate in differentiating between the two entities with widely differing management. Here, we present a case of a 52-year-old male with questionable viability of testis, who was investigated initially using testicular scintigraphy and was further subjected to a regional 18F-FDG PET/CT scan, in view of inconclusive findings with the conventional modalities. [ABSTRACT FROM AUTHOR]

A 28-year-old female presented with an incidentally detected mediastinal mass, found on routine chest X-ray. 18F-fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) was advised to plan course of further management. FDG-PET/CT findings were suggestive of an FDG-avid soft-tissue mass in the left posterior mediastinum in paravertebral location with left pleural effusion. Overall, PET/CT scan findings favored the possibility of a nerve sheath tumor. However, histopathology along with immunohistochemistry confirmed the diagnosis of Castleman disease. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 65-year-old woman suffering who was referred for Fludeoxyglucose positron emission tomography-computed tomography (FDG-PET/CT) to examine lumbar lesion's malignancy. Topics include signet-ring cell gastric carcinoma (SRCG) diagnosis, tracer uptake, and tumor angiogenesis.

The article is presenting a case study in which a 54-year-old diabetic and hypertensive male patient having end-stage renal disease on hemodialysis for the last 15 years was referred for myocardical perfusion scintigraphy (MPS) as perioperative evaluation for renal transplant. A single day standard stress/rest MPS was performed with adenosine as pharmacological stress agent. The article discusses the unexpected detection of pericardial effusion on myocardial perfusion echocardiography.

Background: Assessment of left ventricular mechanical dyssynchrony (LVMD) using phase analysis of gated SPECT-MPI is well established. However, there is little information about the influence of diabetes mellitus on phase analysis. The present work was to evaluate the LVMD in longstanding type II diabetes mellitus (DM) patients with normal gated SPECT-MPI.Methods: Retrospective analysis of 146 (86 type II diabetics for > 5 years' duration and 60 nondiabetics) consecutive patients with normal gated SPECT-MPI and adequate LVEF was done. Sixty age- and sex-matched nondiabetic served as control. LVMD was determined from the cutoff values (> mean + 2 SD) observed for phase standard deviation (PSD) and phase bandwidth (PBW) from the control subjects. Multivariate logistic regression analysis was applied to assess the correlation between various confounding factors.Results: LVMD was detected in 24 (28%) diabetic patients with the pre-defined cut-off values for PSD (> 10.8) and PBW (> 35.6) derived from the controls. Hyperlipidemia, overweight/obesity, duration of DM and its long-term complications were independently associated with LVMD, with long-term complications being the highest risk factor (OR 28.00; P < .001).Conclusion: The evolution time of the patients with type II diabetes mellitus affects the left ventricular mechanical synchrony. [ABSTRACT FROM AUTHOR]

Background: Antimicrobial peptides (AMPs) such as UBI-29-41 offer a distinctive approach for precise detection due to their unique interactions with bacteria and makes them promising candidates for specific and selective imaging. The study was aimed to corroborate the in-house manual synthesis of 68 Ga-NOTA-UBI-29-41, evaluate its uptake in patients with suspected infection, and estimate of patient-specific dosimetry to ensure optimal clinical application. Materials and Methods: 68 Ga-NOTA-UBI-29-41 was synthesized by using a variable amount of UBI-29-41 (60-90 μg) to 555 MBq of Ga-68 in 0.05 M Hydrochloric acid (HCl) and heating the reaction sample for 12 min at 90°C at pH: 3.5-4 to obtain the radiopeptide with high yield and high radiochemical purity (RCP). 68 Ga-NOTA-UBI-29-41 positron emission tomography/Computed tomography (CT) scans at variable timepoints were done to evaluate its biodistribution and maximum uptake time. Furthermore, patient-specific dosimetric estimation was done using the HERMES software. Results: A total of 5 μg/37 MBq (5 μg/mCi) of NOTA-UBI-29-41 for 12 min at 90°C were the optimal parameters to obtain 88%-90% of yield and 98%-99 % of RCP. 68 Ga-NOTA-UBI-29-41 showed expeditious blood clearance and high renal excretion. The optimal time for imaging of infection with 68 Ga-NOTA-UBI-29-41 was found to be at 60 min postinjection ( n = 8). The critical organ was the urinary bladder, receiving an average dose of 138.02 ± 45.92 µSv/MBq, followed by 53.81 ± 13.72 µSv/MBq for kidneys with a mean effective dose of 1.52 ± 0.64 mSv. Conclusion: The protocol for in-house manual labeling of 68 Ga-NOTA-UBI-29-41 was reproducible, providing high yield and RCP. 68 Ga-NOTA-UBI-29-41 administration was found to be safe and nontoxic. The favorable biodistribution and the first-in-human patient-specific dosimetry ensure optimal clinical application.

Purpose: αvβ6 integrin is exclusively expressed in epithelial cells and is upregulated in many carcinomas, such as pancreatic ductal adenocarcinomas (PDACs) and head and neck squamous cell carcinomas (H&NSCCs). Trivehexin is a recently synthesized trimerized αvβ6 integrin selective nonapeptide, which can be labeled with a positron emitter like 68 Ga. This is a pilot study to assess the potential role of 68 Ga-Trivehexin PET/CT in patients with H&NSCC and PDAC and their correlation with αvβ6 integrin expression by the tumor tissue on immunohistochemistry (IHC)., Patients and Methods: Thirty-two patients with suspected H&NSCC (n = 20) or PDAC (n = 12) underwent whole-body 68 Ga-Trivehexin PET/CT and 18 F-FDG PET/CT scans on 2 separate days. All 32 patients underwent biopsy from the tumor site for histopathological diagnosis and IHC for αvβ6 integrin expression. The degree of αvβ6 integrin expression on IHC was scored using the immunoreactive score and modified 4-point immunoreactive score classification., Results: The 68 Ga-Trivehexin PET images demonstrated increased tracer uptake (mean SUV max 5.9 ± 3.3) in the primary and metastatic lesions with good lesion delineation in 8 out of the 9 cases of PDACs. However, FDG PET showed increased tracer uptake in 7 cases (6.2 ± 2.6). Among various cases of H&NSCC, increased uptakes of 68 Ga-Trivehexin (6.6 ± 4.5) and 18 F-FDG (12.7 ± 6.7) were seen in 17 out of the 18 patients. The 2 cases of inflammatory changes with suspected disease recurrence showed increased tracer uptake in 18 F-FDG PET (7.98 ± 3.1) and no significant uptake in 68 Ga-Trivehexin PET (2.2 ± 0.34).IHC showed higher expression of αvβ6 integrins in lesions with higher uptake of 68 Ga-Trivehexin. A higher sensitivity, specificity, and accuracy of 68 Ga-Trivehexin PET over 18 F-FDG PET was seen for detection of primary and metastatic lesions., Conclusions: 68 Ga-Trivehexin is a promising noninvasive molecular imaging agent for tumors expressing αvβ6 integrin, especially in cases where 18 F-FDG PET/CT scan may be suboptimal due to its low uptake, or due to its nonspecific uptake around tumor sites., Competing Interests: Conflicts of interest and sources of funding: The author “Jakub Simecek” is the CEO (Chief Executive Officer) of “TRIMT GmbH.” There is no conflict of interest with respect to the other authors. The pharmaceutical “trivehexin” was provided by TRIMT GmbH. The investigators have not received any fee or financial indemnity from TRIMT GmbH., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Abstract: 212 Pb emerges as a compelling in vivo α-particle generator for targeted α therapy due to its favorable half-life ( t1/2 = 10.6 hours) aligning with the biological half-lives of small peptides and its potent α-particle emissions within the decay series. However, one of the challenges with 212 Pb is to perform appropriate image-guided dosimetry. To date, all the data have been extrapolated from its imaging analog, 203 Pb. We present the first-in-human posttherapy image-guided dosimetric estimates of a single cycle of 212 Pb VMT-α-peptide, administered in a 41-year-old woman with an advanced grade 2 NET. The patient also demonstrated partial response on treatment., Competing Interests: Conflicts of interest and sources of funding: M.K.S. is inventor of the peptide VMT-α-NET and chief science officer of Prospective Therapeutics. There is no conflict of interest with respect to the other authors. The 224 Ra/ 212 Pb generator and the VMT-α-NET peptide were provided by Perspective Therapeutics. The investigators have not received any fee or financial indemnity from Perspective Therapeutics., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc.)