Positron Emission Tomography-computed Tomography Findings Research Articles

Multimodality imaging of ureteral desmoplastic small round cell tumor: a case description and literature analysis of 18F-fluoro-2-deoxy-d-glucose positron emission tomography-computed tomography findings.

Multimodality imaging of ureteral desmoplastic small round cell tumor: a case description and literature analysis of 18F-fluoro-2-deoxy-d-glucose positron emission tomography-computed tomography findings.

Analysis of clinical characteristics and histopathological transcription in 40 patients afflicted by epilepsy stemming from focal cortical dysplasia.

This study aims to comprehensively analyze the clinical characteristics and identify the differentially expressed genes associated with drug-resistant epilepsy (DRE) in patients with focal cortical dysplasia (FCD). A retrospective investigation was conducted from July 2019 to June 2022, involving 40 pediatric cases of DRE linked to FCD. Subsequent follow-ups were done to assess post-surgical outcomes. Transcriptomic sequencing and quantitative reverse transcription polymerase chain reaction (qRT-PCR) were used to examine differential gene expression between the FCD and control groups. Among the 40 patients included in the study, focal to bilateral tonic-clonic seizures (13/40, 32.50%) and epileptic spasms (9/40, 22.50%) were the predominant seizure types. Magnetic resonance imaging (MRI) showed frequent involvement of the frontal (22/40, 55%) and temporal lobes (12/40, 30%). In cases with negative MRI results (13/13, 100%), positron emission tomography/computed tomography (PET-CT) scans revealed hypometabolic lesions. Fused MRI/PET-CT images demonstrated lesion reduction in 40.74% (11/27) of cases compared with PET-CT alone, while 59.26% (16/27) yielded results consistent with PET-CT findings. FCD type II was identified in 26 cases, and FCD type I in 13 cases. At the last follow-up, 38 patients were prescribed an average of 1.27 ± 1.05 anti-seizure medications (ASMs), with two patients discontinuing treatment. After a postoperative follow-up period of 23.50 months, 75% (30/40) of patients achieved Engel class I outcome. Transcriptomic sequencing and qRT-PCR analysis identified several genes primarily associated with cilia, including CFAP47, CFAP126, JHY, RSPH4A, and SPAG1. This study highlights focal to bilateral tonic-clonic seizures as the most common seizure type in patients with DRE due to FCD. Surgical intervention primarily targeted lesions in the frontal and temporal lobes. Patients with FCD-related DRE showed a promising prognosis for seizure control post-surgery. The identified genes, including CFAP47, CFAP126, JHY, RSPH4A, and SPAG1, could serve as potential biomarkers for FCD. This study aimed to comprehensively evaluate the clinical data of individuals affected by focal cortical dysplasia and analyze transcriptomic data from brain tissues. We found that focal to bilateral tonic-clonic seizures were the most prevalent seizure type in patients with drug-resistant epilepsy. In cases treated surgically, the frontal and temporal lobes were the primary sites of the lesions. Moreover, patients with focal cortical dysplasia-induced drug-resistant epilepsy exhibited a favorable prognosis for seizure control after surgery. CFAP47, CFAP126, JHY, RSPH4A, and SPAG1 have emerged as potential pathogenic genes for the development of focal cortical dysplasia.

18Fluorodeoxyglucose positron emission tomography-computed tomography findings in bilateral adrenal metastases in renal cell carcinoma

Abstract Bilateral adrenal metastases is a rare manifestation which can be seen in malignancies such as breast, lung carcinoma and melanomas. Adrenal metastases are usually detected on one side or more rarely on both sides. Molecular imaging with 18fluorodeoxyglucose positron emission tomography-computed tomography often shows unilateral or bilateral adrenal metastases in various malignancies. Here, we present a case of renal cell carcinoma that presented with widespread skeletal and bilateral adrenal metastases.

Accurate Preoperative Evaluation of the Location of Esophagogastric Junction Adenocarcinoma Using Positron Emission Tomography-Computed Tomography.

The surgical procedure for esophagogastric junction (EGJ) adenocarcinoma usually depends on the location of its epicenter or proximal margin, but accurate evaluation of these positions is often difficult. The usefulness of positron emission tomography-computed tomography (PET-CT) for this purpose is unknown. Between June 2005 and February 2015, we enrolled 30 patients with cT2-4 EGJ adenocarcinoma (Siewert type I/II) who underwent surgical resection. We ascertained the sensitivity and specificity of preoperative PET-CT for identifying the primary tumor and regional lymph node metastasis, and compared PET-CT and pathological findings in terms of the distance from the EGJ to the tumor epicenter or proximal tumor margin. PET-CT detected the primary tumor with a sensitivity of 97% (29/30), and detected lymph node metastasis with a sensitivity and specificity of 22% (4/18) and 100% (8/8), respectively. No significant association was observed between the maximal standardized uptake value and histological type, tumor size, or pT status. Regarding the accuracy of evaluating tumor location, the median differences between PET-CT and pathological measurements were .6cm for the tumor epicenter and .5cm for the proximal margin from the EGJ. PET-CT and pathological findings showed agreement regarding Siewert classification type (I or II) and lengths of esophageal involvement exceeding 4cm or 2cm in 77% (10/13), 85% (11/13), and 85% (11/13) of cases, respectively. PET-CT had high sensitivity for primary EGJ adenocarcinoma. It may effectively locate the tumor epicenter and proximal margin and thus help clinicians determine the optimal surgical procedure.

PET-CT underestimates the true pathological extent of disease at lymphadenectomy for melanoma patients after systemic therapy

IntroductionModern systemic therapy has revolutionized the treatment of melanoma. Currently, patients with clinically involved lymph nodes require lymphadenectomy with associated morbidities. Positron Emission Tomography – Computed Tomography (PET-CT) has demonstrated accuracy in melanoma detection and response to therapy. We aimed to identify whether a PET-CT directed lymphatic resection after systemic therapy is oncologically sound. Materials and methodsRetrospective review of patients who underwent lymphadenectomy after systemic therapy for melanoma with a preoperative PET-CT. Examined demographic, clinical, and perioperative parameters including extent of disease, systemic therapy and response, and PET-CT findings compared to pathological outcomes. We compared patients with “as or less than expected” outcomes on pathology against those with “more than expected” pathological outcomes. ResultsThirty-nine patients met inclusion criteria. In 28 (71.8%), pathological outcomes were “as or less than expected” by PET-CT, and in 11 (28.2%) pathological outcome were “more than expected”. “More than expected” occurred more frequently with advanced disease at presentation with 75% presenting with regional/metastatic disease versus only 42.9% in the “as or less than expected” group (p = 0.015). Poor response to therapy also trended towards the “more than expected” group with only 27.3% favorable response versus 53.6% favorable response in the “as or less than expected” group, not statistically significant. Extent of disease on imaging failed to predict pathological concordance. ConclusionPET-CT underestimates pathological extent of disease in the lymphatic basin in 30% of patients after systemic therapy. We failed to identify predictors of more extensive disease and warn against limited PET-CT directed lymphatic resections.

Development and validation of a nonenhanced CT based radiomics model to detect brown adipose tissue.

Purpose: It has been reported that brown adipose tissue (BAT) has a protective effect regarding cardiovascular disease. Positron emission tomography-computed tomography (PET-CT) is the reference method for detecting active BAT; however, it is not feasible to screen for BAT due to the required radionuclides and high-cost. The purpose of this study is to develop and validate a nonenhanced CT based radiomics model to detect BAT and to explore the relationship between CT radiomics derived BAT and cardiovascular calcification. Patients and methods: 146 patients undergoing 18F-FDG PET-CT were retrospectively included from two centers for model development (n = 86) and external validation (n = 60). The data for the model development were randomly divided into a training cohort and an internal validation cohort with a 7:3 ratio, while the external validation data were divided 1:1 into a propensity score matching (PSM) cohort and a randomly sex matched cohort. Radiomics features of BAT and non-BAT depots were extracted from regions of interest (ROI) on nonenhanced CT corresponding to PET studies. Inter-class correlation coefficient (ICC) and Pearson's correlation analysis were performed to select radiomics features with high consistency. Next, least absolute shrinkage and selection operator (LASSO) with linear regression model was used to select radiomics features for model construction. Support vector machine (SVM) was used to develop the model and a radiomics score (RS) was calculated for each depot. The diagnostic performance of the radiomics model was evaluated both on a per-depot and per-patient basis by calculating the area under the receiver operating characteristic curve (AUROC). We further divided patients into BAT-RS group and non-BAT-RS group based on radiomics score and compared their cardiovascular calcification by calculating calcium volume and score. Results: A total of 22 radiomics features were selected for model construction. On a per-depot basis, the AUROCs were 0.87 (95% CI: 0.83-0.9), 0.85 (95% CI: 0.79-0.90), 0.72 (95% CI: 0.67-0.77) and 0.74 (95% CI: 0.69-0.79) for detecting BAT in the training, internal validation, external validation 1 and external validation 2 cohorts, respectively. On a per-patient basis, the radiomics model had high AUROCs of 0.91 (95% CI: 0.84-0.98), 0.77 (95% CI: 0.61-0.92) and 0.85 (95% CI: 0.72-0.98) in the training, external validation 1 and external validation 2 cohorts, respectively. When grouping based on the radiomics model, the BAT-RS group had lower odds of coronary artery calcium (CAC) and thoracic aorta calcium (TAC) compared with the non-BAT-RS group (CAC: 2.8% vs. 20.3%, p = 0.001; TAC: 19.4% vs. 39.2%, p = 0.009). The BAT-RS group had less CAC volume (4.1 ± 4.0 mm3 vs. 147.4 ± 274.3 mm3; p = 0.001), CAC score (2.8 ± 3.0 vs. 169.1 ± 311.5; p = 0.001), TAC volume (301.4 ± 450.2 mm3 vs. 635.3 ± 1100.7 mm3; p = 0.007) and TAC score (496.2 ± 132.6 vs. 749.2 ± 1297.3; p = 0.007) than the non-BAT-RS group. Conclusion: We developed and validated a nonenhanced CT based reliable radiomics model for detecting BAT with PET-CT findings as reference standard. Radiomics signatures from nonenhanced CT can reliably detect BAT and have promising potential to be used in routine clinical settings. Importantly, our study showed that patients with BAT had less cardiovascular calcification.

Clinical predictors and implications of cardiac inflammation detected on positron emission tomography (PET) in patients referred for premature ventricular complex (PVC) ablation.

Positron emission tomography computed tomography (PET-CT) is not routinely used for premature ventricular complexes (PVCs). Whether specific clinical factors are associated with abnormal PET-CT results is not clear. The treatment courses and baseline characteristics of consecutive patients in a single center between 2012 and 2021, age > 18years old, and who received 18F-fluorodeoxyglucose (FDG) PET-CT imaging for evaluation of PVCs were retrospectively analyzed. A total of 102 patients was included. Of these, 27 patients (26.4%) had abnormal PET-CT and 61 (59.8%) had normal imaging. Abnormal PET-CT findings were associated with non-sustained ventricular tachycardia (NSVT) (95.2% vs. 52.6%, p = 0.001), higher number of PVC morphologies (2.29 ± 0.7 vs. 1.31 ± 0.6, p < 0.001), greater PVC coupling interval dispersion (72.47 ± 66.4ms vs. 13.42 ± 17.9ms, p < 0.001), and greater likelihood of fast heart rate dependent PVCs (78.5% vs. 38.2%, p = 0.017). Fourteen (51.8%) patients had an abnormal PET-CT and abnormal late gadolinium enhancement (LGE). Patients with abnormal PET-CT were more frequently treated with immunosuppression (81.4% vs. 3.2%, p < .0001) than with catheter ablation (11.1% vs. 45.9%, p = 0.002) compared to the normal PET-CT group. Over a median follow-up of 862days (IQR 134, 1407), PVC burden decreased in both groups [from 23 ± 16% to 9 ± 10% (p < 0.001) in abnormal PET-CT group and from 21 ± 15% to 7 ± 10% (p < 0.001) in normal PET-CT group]. Abnormal PET-CT findings were more commonly associated with NSVT, multiform PVCs, greater PVC coupling interval dispersion, and fast heart rate dependent PVCs. LGE was not sensitive for detecting inflammation. Immunosuppression was effective in managing PVCs with abnormal PET-CT.

Value of 68Ga-labeled bombesin antagonist (RM2) in the detection of primary prostate cancer comparing with [18F]fluoromethylcholine PET-CT and multiparametric MRI—a phase I/II study

ObjectivesThe bombesin derivative RM2 is a GRPr antagonist with strong binding affinity to prostate cancer (PCa). In this study, the impact of [68Ga]Ga-RM2 positron emission tomography-computed tomography (PET-CT) for the detection of primary PCa was compared with that of [18F]FCH PET-CT and multiparametric magnetic resonance imaging (mpMRI).MethodsThis phase I/II study was conducted in 30 biopsy-positive PCa subjects. The patients were stratified into high (10 patients), intermediate (10 patients), and low risk (10 patients) for extraglandular metastases as defined by National Comprehensive Cancer Network (NCCN) criteria (NCCN Clinical Practice Guidelines in Oncology, 2016). The prostate gland was classified in 12 anatomic segments for data analysis of the imaging modalities as well as histopathologic findings. The segment with the highest radiotracer uptake was defined as the “index lesion.” All cases were scheduled to undergo prostatectomy with pelvic lymph node (LN) dissection in intermediate- and high-risk patients. Intraprostatic and pelvic nodal [68Ga]Ga-RM2 and [18F]FCH PET-CT findings were correlated with mpMRI and histopathologic results.ResultsOf the 312 analyzed regions, 120 regions (4 to 8 lesions per patient) showed abnormal findings in the prostate gland. In a region-based analysis, overall sensitivity and specificity of [68Ga]Ga-RM2 PET-CT in the detection of primary tumor were 74% and 90%, respectively, while it was 60% and 80% for [18F]FCH PET-CT and 72% and 89% for mpMRI. Although the overall sensitivity of [68Ga]Ga-RM2 PET-CT was higher compared to that of [18F]FCH PET-CT and mpMRI, the statistical analysis showed only significant difference between [68Ga]Ga-RM2 PET-CT and [18F]FCH PET-CT in the intermediate-risk group (p = 0.01) and [68Ga]Ga-RM2 PET-CT and mpMRT in the high-risk group (p = 0.03). In the lesion-based analysis, there was no significant difference between SUVmax of [68Ga]Ga-RM2 and [18F]FCH PET-CT in the intraprostatic malignant lesions ([68Ga]Ga-RM2: mean SUVmax: 5.98 ± 4.13, median: 4.75; [18F]FCH: mean SUVmax: 6.08 ± 2.74, median: 5.5; p = 0.13).Conclusions[68Ga]Ga-RM2 showed promising PET tracer for the detection of intraprostatic PCa in a cohort of patients with different risk stratifications. However, significant differences were only found between [68Ga]Ga-RM2 PET-CT and [18F]FCH PET-CT in the intermediate-risk group and [68Ga]Ga-RM2 PET-CT and mpMRT in the high-risk group. In addition, GRP-R-based imaging seems to play a complementary role to choline-based imaging for full characterization of PCa extent and biopsy guidance in low- and intermediate-metastatic-risk PCa patients and has the potential to discriminate them from those at higher risks.Key Points• [68Ga]Ga-RM2 is a promising PET tracer with a high detection rate for intraprostatic PCa especially in intermediate-risk prostate cancer patients.• GRPr-based imaging seems to play a complementary role to choline-based or PSMA-based PET/CT imaging in selected low- and intermediate-risk PCa patients for better characterization and eventually biopsy guidance of prostate cancer disease.

Unexpected Rare Association of Secondary Breast, Thyroid, and Ovarian Lymphomas in a Female Patient with Burkitt Lymphoma: PET-CT Findings.

We report the case of a 15-year-old female, followed for Burkitt lymphoma with initial ovarian presentation. Positron emission tomography-computed tomography (PET-CT) with 18 F-fluorodeoxyglucose ( 18 F-FDG) performed to evaluate initial extension assessment showed an unexpected association with secondary breast, thyroid, and ovarian lymphomas. To our knowledge, this association is very rare, unusual, and these extranodal presentations have been reported in literature as a separate case report. Authors highlight performance of PET-CT with 18 F-FDG to determinate the secondary origin of this multiglandular involvement, to establish a lesional map of the whole body, and to contribute to the therapeutic decision.

18F-fluorodesoxyglucose positron emission tomography/computed tomography in extramedullary multiple myeloma

18F-fluorodesoxyglucose positron emission tomography/ computed tomography (PET-CT) has a high sensitivity and specificity to detect medullary and extramedullary lesions in multiple myeloma (MM). To describe the findings of PET-CT in extramedullary multiple myeloma (EMM) at diagnosis and at relapse, and correlate its results with clinical variables, response to treatment and survival. Review of medical records and PET-CT reports of 39 patients with multiple myeloma (MM) who had at least one PET-CT study, treated between January 1, 2015, and January 1, 2019 at a clinical hospital. The Standard Uptake Values for each hypermetabolic lesion were not described in PET-CT reports. Fifteen patients had an EMM and in eight, without a previous clinical suspicion, PET-TC lead to the diagnosis. The mortality rate in the 39 patients with MM was 46%. Sixty seven percent of deaths occurred in patients with EMM. PET-TC was useful to diagnose EMM. However, a standardization in PETCT reports would be required to unify criteria. As previously reported, EMM had a greater aggressiveness and lower survival.

Shoulder adhesive capsulitis in cancer patients undergoing positron emission tomography - computed tomography and the association with shoulder pain.

BACKGROUNDAdhesive capsulitis is a relatively common condition that can develop in cancer patients during treatment. Positron emission tomography - computed tomography (PET-CT) is routinely performed as a follow-up study in cancer patients after therapy. Being aware of PET-CT findings to suggest shoulder adhesive capsulitis may help to alert clinicians for the diagnosis of unsuspected shoulder capsulitis.AIMTo assess the association of shoulder adhesive capsulitis with cancer/therapy type and symptoms in cancer patients undergoing PET-CT.METHODSOur prospective study received Institutional Review Board approval. Written informed consent was obtained from all patients, who answered a questionnaire regarding shoulder pain/stiffness at the time of PET-CT study, between March 2015 and April 2019. Patients with advanced glenohumeral arthrosis, metastatic disease or other mass in the shoulder, or shoulder arthroplasty were excluded. Patterns of shoulder capsule 18F-fluorodeoxyglucose (FDG) uptake were noted. Standard Uptake Value (SUV)max and SUVmean values were measured at rotator interval (RI) and deltoid muscle in bilateral shoulders. Normalized SUV (SUV of RI/SUV of deltoid muscle) was also calculated. We assessed if SUV values are different between symptomatic and asymptomatic patients in both shoulders. Covariates were age, gender, and therapy type (surgery, chemotherapy, radiation). Wilcoxon rank sum tests were used to compare unadjusted marginal differences for age, SUV measurements between symptomatic and asymptomatic patients. Multiple linear regression models were used to examine the relationship between right or left shoulder SUV measurements and symptom status, after adjusting for covariates. Statistical significance level was set at P < 0.05.RESULTSOf 252 patients initially enrolled for the study (mean age 66 years, 67 symptomatic), shoulder PET-CT data were obtained in 200 patients (52 were excluded due to exclusion criteria above). The most common cancer types were lymphoma (n = 61), lung (n = 54) and breast (n = 53). No significant difference was noted between symptomatic and asymptomatic patients in terms of age, gender, proportion of patients who had surgical therapy and radiation therapy. A proportion of patients who received chemotherapy was higher in patients who were asymptomatic in the right shoulder compared to those symptomatic in the right shoulder (65% vs 48%, P = 0.012). No such difference was seen for the left shoulder. In both shoulders, SUVmax and SUVmean were higher in symptomatic shoulders than asymptomatic shoulders (Left SUVmax 2.0 vs 1.6, SUVmean 1.6 vs 1.3, both P < 0.002; Right SUVmax 2.2 vs 1.8, SUVmean 1.8 vs 1.5, both P < 0.01). For lung cancer patients, bilateral RI SUVmax and SUVmean values were higher in symptomatic shoulders than asymptomatic shoulders. For other cancer patients, symptomatic patients had higher left RI SUVmax/mean than asymptomatic patients after adjustment.CONCLUSIONIn symptomatic patients metabolic activities in RI were higher than asymptomatic patients. Adhesive capsulitis should be considered in cancer patients with shoulder symptoms and positive FDG uptake in RI.

Difference in Computed Tomography Image Quality between Central Vein and Peripheral Vein Enhancement in Treatment Naive Esophageal Cancer Patients.

Simple SummaryA chest CT via central vein enhancement not only eliminates peripheral vein regurgitation but also provides better image quality that facilitates precise clinical staging. A chest CT via central vein enhancement may be considered after tissue proof in order to better discriminate disease severity.The differences in chest computed tomography (CT) image quality may affect the tumor stage. The aim of this study was to compare the image quality and accuracy of chest CT via central vein and peripheral vein enhancement. Fifty consecutive patients were enrolled from a tertiary medical center in Taiwan from May 2016 to March 2019. All the patients received a chest CT via central vein enhancement prior to neoadjuvant concurrent chemoradiation in order to compare the chest CT that was obtained via the peripheral vein. In addition, blind independent central reviews of chest CT via central vein and peripheral vein enhancement were conducted. For T and N stage, chest CT via central vein enhancement had a greater consistency with endoscopic ultrasonography and positron-emission tomography-computed tomography findings (kappa coefficients 0.4471 and 0.5564, respectively). In addition, chest CT via central vein enhancement also showed excellent agreement in the blind independent central review (kappa coefficient 0.9157). The changes in the T and N stage resulted in stage migration in 16 patients. Chest CT via central vein enhancement eliminated peripheral vein regurgitation and also provided more precise clinical staging. This study is registered under the registered NCT number 02887261.

Incidental lung findings in a COVID-19 patient on 18F-FDG PET/CT done for preoperative evaluation of Marjolin's ulcer-first report from Chhattisgarh.

The aim of this case is to illustrate the18F-fluorodeoxyglucose (FDG) positron emission tomography-computed tomography findings of a patient who was admitted in AIIMS, Raipur, for the preoperative evaluation of Marjolin ulcer and was later diagnosed with COVID-19 infection. Apart from the primary lesion in the right foot and pelvic lymph nodes, the scan revealed mild FDG-avid basal ground-glass opacities in bilateral lung fields with mediastinal and hilar lymph nodal involvement, in an otherwise asymptomatic patient.

Hepatic Alveolar Echinococcosis: Predictive Biological Activity Based on Radiomics of MRI.

Background To evaluate the role of radiomics based on magnetic resonance imaging (MRI) in the biological activity of hepatic alveolar echinococcosis (HAE). Methods In this study, 90 active and 46 inactive cases of HAE patients were analyzed retrospectively. All the subjects underwent MRI and positron emission tomography computed tomography (PET-CT) before surgery. A total of 1409 three-dimensional radiomics features were extracted from the T2-weighted MR images (T2WI). The inactive group in the training cohort was balanced via the synthetic minority oversampling technique (SMOTE) method. The least absolute shrinkage and selection operator (LASSO) regression method was used for feature selection. The machine learning (ML) classifiers were logistic regression (LR), multilayer perceptron (MLP), and support vector machine (SVM). We used a fivefold cross-validation strategy in the training cohorts. The classification performance of the radiomics signature was evaluated using receiver operating characteristic curve (ROC) analysis in the training and test cohorts. Results The radiomics features were significantly associated with the biological activity, and 10 features were selected to construct the radiomics model. The best performance of the radiomics model for the biological activity prediction was obtained by MLP (AUC = 0.830 ± 0.053; accuracy = 0.817; sensitivity = 0.822; specificity = 0.811). Conclusions We developed and validated a radiomics model as an adjunct tool to predict the HAE biological activity by combining T2WI images, which achieved results nearly equal to the PET-CT findings.

18F-Fluorodeoxyglucose Positron-Emission Tomography/Computed Tomography Detected Inguinal Lymph Nodal Metastasis from Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) usually metastasizes to the regional abdominal lymph node, lungs, and bones. Nonregional lymph node involvement by HCC in the absence of regional lymph nodes is rare. We describe the 18F-fluorodeoxyglucose positron-emission tomography-computed tomography findings of an HCC patient with histopathologically proven inguinal lymph nodal metastasis in the absence of regional lymph nodal metastases.

In the evaluation of patients with skull base osteomyelitis, does 18F-FDG PET CT have a role?

To evaluate the diagnostic performance of regional fluorine-18 fluorodeoxyglucose (F-FDG) positron emission tomography-computed tomography (PET-CT) in patients with skull base osteomyelitis (SBO) and to compare with magnetic resonance imaging (MRI) whenever available. A total of 77 patients (male:female = 56:21; mean age 66.4 ± 9.4 years) with clinically suspected SBO, who underwent regional F-FDG PET-CT were included in this retrospective study. F-FDG PET-CT images were analyzed for presence, localization and intensity of FDG uptake. Diagnostic performance of F-FDG PET-CT was analyzed based on histopathology, culture, and clinical/imaging follow-up. The agreement analysis between F-FDG PET-CT and MRI findings was performed in 56 patients. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of F-FDG PET-CT for diagnosing SBO were 96.7, 93.3, 98.3, 87.5, and 96.1%, respectively. The average SUVmax of the lesions was 5.9 ± 3.5. The SUVmax of the fungal lesions was lower than that of bacterial lesions with P-value of <0.001. On comparing variables like C-reactive protein, erythrocyte sedimentation rate, and SUVmax for prediction of recurrence/progression, by plotting an ROC curve, the SUVmax was found to be an independent prognostic marker. 56 out of 77 patients had undergone both F-FDG PET-CT and MRI. The agreement analysis between the modalities showed almost perfect agreement for delineation of soft tissue and bony involvement with κ values of 0.82 and 0.81, respectively. F-FDG PET-CT is a sensitive tool in evaluation of patients with SBO. It shows a very good agreement with the MRI. It plays a critical role in treatment response evaluation.

Rare Case of Cardiac Metastasis in a Patient with Cutaneous Squamous Cell Carcinoma of Foot Detected on 18F-Fluorodeoxyglucose Positron Emission Tomography-Computed Tomography.

Cutaneous squamous cell carcinoma (SCC) metastasizes most commonly to the regional lymph nodes and lungs. Metastasis to heart, although described in literature, is a very rare phenomenon. We present the 18F-fluorodeoxyglucose positron emission tomography–computed tomography findings in a 50-year-old woman who was a biopsy-proven case of SCC left foot, showing cardiac metastasis in addition to lymph nodes, lungs, and skeletal metastases.

Adrenocortical Carcinoma with Inferior Vena Cava Thrombus on 18F-FDG-PET-Computed Tomography.

Adrenocortical carcinoma (ACC) is a rare and highly aggressive malignant neoplasm which can produce intravascular extension into the inferior vena cava (IVC) and can rarely extend into the right atrium. We describe the 18F Fluorodeoxyglucose Positron Emission Tomography-Computed Tomography findings of a 57-year-old man diagnosed with ACC with IVC thrombus extending up to the right atrium.

P219 THE ROLE OF PET-CT IN THE EVALUATION OF LYMPH NODE INVOLVEMENT IN ESOPHAGEAL AND GASTROESOPHAGEAL JUNCTION CARCINOMA - A 5-YEAR SINGLE CENTER EXPERIENCE

Abstract Aim To determine the efficacy of positron emission tomography-computed tomography (PET-CT) in the evaluation of lymph node status during preoperative staging on patients with esophageal and gastrοesophageal junction carcinoma compared to the final histopathological findings. Background &amp; Methods Data on patients that underwent esophagectomy from 01/03/2014 to 01/03/2019 were prospectively collected and retrospectively reviewed. Based on the medical records, the following parameters were extracted and analyzed: patient demographics, histopathological parameters, surgical and oncological outcomes. All patients were staged according to the AJCC 8th edition. Results A total of 79 patients underwent Ivor Lewis or McKeown esophagectomy for either squamous cell carcinoma (n= 7 patients) or adenocarcinoma of esophagus or gastroesophageal junction (n= 72 patients). In 60 cases, clinical staging was conducted without performing PET- CT, while 19 cases underwent PET-CT. Among the 19 patients, 16 (84.2%) were men, and 3 (15.8 %) were women. Mean age was 62 years, (range 41- 72). Mean nodal harvest per patient was 30.6 lymph nodes. Twelve out of 19 patients (63.2%) revealed lymph node invasion, with a mean of 5.6 positive lymph nodes per patient. PET-CT identified the primary tumor in all 19 patients (100%). PET-CT demonstrated 100% compliance with the final histopathological reports regarding N status in only 5 out of 19 cases (26.3%). Four patients were staged as N0 both pre- and postoperatively, while one was deemed positive by PET-CT in right paracardial lymph nodes which was histopathologically confirmed. In other 4 patients (21.1%), PET-CT was 100% false negative, whereas in 3 patients (15.8%) PET-CT was 100% false positive. In the remaining 7 patients, PET-CT findings were in accordance with the pathology report in 7 out of 25 examined lymph node stations, false positive in 9 out of 25 and false negative in 9 out of 25. Conclusion PET-CT seems to have a considerable number of false positive and false negative results in esophageal cancer in our study as far as N-staging is concerned. Further studies with larger sample size are needed to reach more conclusive results.

Evaluation of the Prognostic Value of Positron Emission Tomography-Computed Tomography (PET-CT) at Diagnosis and Follow-up in Transplant-Eligible Newly Diagnosed Multiple Myeloma (TE NDMM) Patients Treated in the Phase 3 Cassiopeia Study: Results of the Cassiopet Companion Study

Evaluation of the Prognostic Value of Positron Emission Tomography-Computed Tomography (PET-CT) at Diagnosis and Follow-up in Transplant-Eligible Newly Diagnosed Multiple Myeloma (TE NDMM) Patients Treated in the Phase 3 Cassiopeia Study: Results of the Cassiopet Companion Study