UNASSIGNED: 18F-fluorodeoxy-2-deoxy-D-glucose (FDG) positron emission tomography (PET) is used with high sensitivity in human medicine for initial staging and treatment planning of cutaneous squamous cell carcinoma (SCC). To the best of our knowledge, 18F-FDG PET/computed tomography (CT) has not been used for canine cutaneous SCC with lymph node metastasis.
UNASSIGNED: A 13 year-old spayed female Maltese had rapidly growing flank SCC, which had previously recurred twice. Radiography revealed no metastases. On PET/CT imaging, increased FDG uptake was observed not only in the flank but also in the left axillary lymph node and left inguinal lymph node (standardized uptake value max [SUVmax]: 8.602, 5.354, and 1.96, respectively). Despite the evidence of metastasis, palliative skin mass resection with a 3-cm margin and lymph node dissection were performed. Histopathological examination confirmed the presence of metastases in both lymph nodes.
UNASSIGNED: 18F-FDG PET/CT is valuable for the detection of metastatic tumors in various organs. Cutaneous SCC can accumulate 18F-FDG, making it detectable on PET/CT. In this dog with flank SCC, 18F-FDG-PET/CT showed high SUVmax values, indicating its potential for tumor assessment. In veterinary medicine, SUVmax values of 2.5-3.5 are commonly used to identify metastatic lymph nodes in other cancers. Therefore, the interpretation of an SUVmax of 1.96 in an inguinal lymph node for metastatic involvement may be uncertain. Owing to the partial volume effect, 18F-FDG PET/CT has limited sensitivity in identifying LN metastases, particularly in cases of small lesions. Lower SUVmax values adjusted for smaller sizes may better distinguish between benign and malignant lymph nodes. Hence, combining differentiated SUVmax cut-offs based on lymph node size with CT assessment could enhance lymph node evaluation and assist in surgical planning.

The aim of our retrospective study is to develop and assess an imaging-based model utilizing 18F-FDG PET parameters for predicting the five-year survival in non-small-cell lung cancer (NSCLC) patients after curative surgery. A total of 361 NSCLC patients who underwent curative surgery were assigned to the training set (n = 253) and the test set (n = 108). The LASSO regression model was used to construct a PET-based risk score for predicting five-year survival. A hybrid model that combined the PET-based risk score and clinical variables was developed using multivariate logistic regression analysis. The predictive performance was determined by the area under the curve (AUC). The individual features with the best predictive performances were co-occurrence_contrast (AUC = 0.675) and SUL peak (AUC = 0.671). The PET-based risk score was identified as an independent predictor after adjusting for clinical variables (OR 5.231, 95% CI 1.987-6.932; p = 0.009). The hybrid model, which integrated clinical variables, significantly outperformed the PET-based risk score alone in predictive accuracy (AUC = 0.771 vs. 0.696, p = 0.022), a finding that was consistent in the test set. The PET-based risk score, especially when integrated with clinical variables, demonstrates good predictive ability for five-year survival in NSCLC patients following curative surgery.

UNASSIGNED: [18F]FDG PET/CT noninvasively disproves acute kidney allograft rejection (AR) in kidney transplant recipients (KTRs) with suspected AR. However, the correlation of biopsy-based Banff vs. PET/CT-based scores of acute inflammation remains unknown, as does the prognostic performance of [18F]FDG PET/CT at one year post suspected AR.
UNASSIGNED: From 2012 to 2019, 114 [18F]FDG-PET/CTs were prospectively performed in 105 adult KTRs who underwent per cause transplant biopsies. Ordinal logistic regression assessed the correlation between the extent of histological inflammation and the mean standardized [18F]FDG uptake values (mSUVmean). Functional outcomes of kidney allografts were evaluated at one year post per cause biopsy and correlated to mSUVmean.
UNASSIGNED: A significant correlation between mSUVmean and acute Banff score was found, with an adjusted R 2 of 0.25. The mSUVmean was significantly different between subgroups of \"total i\", with 2.30 ± 0.71 in score 3 vs. 1.68 ± 0.24 in score 0. Neither the function nor the survival of the graft at one year was statistically related to mSUVmean.
UNASSIGNED: [18F]FDG-PET/CT may help noninvasively assess the severity of kidney allograft inflammation in KTRs with suspected AR, but it does not predict graft outcomes at one year.

Nowadays, the utility of positron emission tomography/computed tomography (PET/CT) is well established in nasopharyngeal carcinoma (NPC). The incidence of NPC in the West population, especially in children, is very low. We present the first Italian case of a pediatric patient with NPC followed up with 18F-fluorodeoxyglucose (18F-FDG) PET/CT scan in addition to the standard follow-up imaging methods, including CT and magnetic resonance imaging. The 18F-FDG PET/CT scan was helpful in discriminating between metastatic and benign osseous lesions, thereby helping clinicians to determine the most appropriate therapeutic regimen. These findings support the clinical utility of 18F-FDG PET/CT in the diagnostic work-up of pediatric patients with NPC.
Günümüzde nazofaringeal karsinomda (NFK) pozitron emisyon tomografisi/bilgisayarlı tomografinin (PET/BT) kullanımı iyice yerleşmiştir. Batı popülasyonunda, özellikle de pediatrik yaşta NFK’nin görülme sıklığı çok düşüktür. BT ve manyetik rezonans görüntüleme dahil olmak üzere standart takip görüntüleme yöntemlerine ek olarak 18F-florodeoksiglukoz (18F-FDG) PET/BT taraması yoluyla takip edilen NFK’li ilk İtalyan pediatrik hastayı sunuyoruz. 18F-FDG PET/BT taraması, metastatik ve iyi huylu kemik lezyonları arasında ayrım yapılmasında ve klinisyenlerin en uygun terapötik rejimi belirlemesine yardımcı olmuştur. Bu bulgular, NFK’li pediatrik hastaların tanısal çalışmalarında 18F-FDG PET/BT taramasının klinik faydasını desteklemektedir.

UNASSIGNED: Primary liver tumors constitute one of the most common tumors. These are aggressive tumors with poor survival. Fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT), most commonly used functional imaging, shows limited tracer retention and poor tumor to background ratios (TBR). Novel 68Ga-fibroblast-activation-protein inhibitor (FAPI) PET/CT has shown better tracer uptake and detection efficacy in liver tumors. However, most of the available literature is limited to single center studies with limited number of patients. So, we tried to review and analyze the head-to-head comparison of 18F-FDG PET/CT and 68Ga-FAPI PET/CT in evaluation of liver tumors.
UNASSIGNED: Literature available on head to head comparison of diagnostic accuracy of 18F-FDG PET/CT and 68Ga-FAPI PET/CT was searched in databases like PubMed, SCOPUS, EMBASE and Google Scholar for published original studies till April 2023. The relevant studies were selected and assessed using the Revised Tool for the Quality Assessment of Diagnostic Accuracy Studies-2 checklist. A random-effect model was used for calculating pooled sensitivity and specificity. They were represented with 95% confidence intervals (95% CI) and demonstrated in Forest plots. I-square statistic was used to assess heterogeneity in the studies.
UNASSIGNED: Pooled sensitivity and specificity of FAPI PET/CT and 18F-FDG PET/CT for detection of primary liver tumors was 94.3% (95% CI: 90.6-96.8%); 89.3% (95% CI: 71.8-97.7%) and 56.1% (95% CI: 49.7-62.5%); 96.4% (95% CI: 81.7-99.9%) respectively. Pooled sensitivity for detection of extrahepatic metastatic disease was 92.2% (range: 88.1-100%; 95% CI: 87.8-95.4%) and 72.4% (range: 69.8-76.5; 95% CI: 65.9-78.2%) respectively. Also, the maximum standardized uptake value (SUVmax) and TBR were higher for FAPI PET/CT than 18F-FDG PET/CT in the included studies.
UNASSIGNED: Overall, FAPI PET/CT showed higher sensitivity for detection of liver tumors with better SUVmax and TBR than 18F-FDG PET/CT.
UNASSIGNED: Primer karaciğer tümörleri en sık görülen tümörlerdendir. Bunlar hayatta kalma oranı düşük olan agresif tümörlerdir. En sık kullanılan fonksiyonel görüntüleme olan florodeoksiglukoz (FDG) pozitron emisyon tomografisi/bilgisayarlı tomografi (PET/BT), sınırlı radyofarmasötik tutulumu ve zayıf tümör/arka plan oranları (TBR) gösterir. Yeni 68Ga-fibroblast aktivasyon protein inhibitörü (FAPI) PET/BT, karaciğer tümörlerinde daha iyi radyofarmasötik tutulumu ve tespit etkinliği göstermiştir. Ancak mevcut literatürün çoğu, sınırlı hasta sayısıyla yapılan tek merkezli çalışmalarla sınırlıdır. Bu nedenle, karaciğer tümörlerinin değerlendirilmesinde 18F-FDG PET/BT ve 68Ga-FAPI PET/BT’nin birebir karşılaştırmasını gözden geçirip analiz etmeye çalıştık.
UNASSIGNED: 18F-FDG PET/BT ve 68Ga-FAPI PET/BT’nin tanısal doğruluğunun birebir karşılaştırılması konusunda mevcut literatür, Nisan 2023’e kadar yayınlanmış araştırma makaleleri için PubMed, SCOPUS, EMBASE ve Google Scholar gibi veritabanlarında tarandı. İlgili çalışmalar Tanısal Doğruluk Çalışmalarının Kalite Değerlendirmesi için Gözden Geçirilmiş Araç-2 kontrol listesi kullanılarak seçilmiş ve değerlendirilmiştir. Birleştirilmiş duyarlılığı ve özgüllüğü hesaplamak için rastgele etki modeli kullanıldı. Bunlar %95 güven aralıklarıyla (%95 GA) temsil edildi ve Orman grafiklerinde gösterildi. Çalışmalardaki heterojenliği değerlendirmek için I-kare istatistiği kullanıldı.
UNASSIGNED: Primer karaciğer tümörlerinin tespiti için FAPI PET/BT’nin havuzlanmış duyarlılığı ve özgüllüğü sırasıyla %94,3 (%95 GA: %90,6-96,8) ve %89,3 (%95 GA: %71,8-97,7); 18F-FDG PET/BT’nin havuzlanmış duyarlılığı ve özgüllüğü sırasıyla %56,1 (%95 GA: %49,7-62,5) ve %96,4 (%95 GA: %81,7-99,9) idi. Ekstrahepatik metastatik hastalığın saptanması için havuzlanmış duyarlılık FAPI PET/BT ve 18F-FDG PET/BT için sırasıyla %92,2 (aralık: %88,1-100; %95 GA: %87,8-95,4) ve %72,4 (aralık: 69,8-76,5; %95 GA: %65,9-78,2) idi. Ayrıca, dahil edilen çalışmalarda FAPI PET/BT için maksimum standardize tutulum değeri (SUVmaks) ve TBR, 18F-FDG PET/BT’den daha yüksekti.
UNASSIGNED: Genel olarak, FAPI PET/BT, karaciğer tümörlerinin tespitinde 18F-FDG PET/BT’ye göre daha iyi SUVmaks ve TBR ile daha yüksek duyarlılık gösterdi.

Background: Identifying programmed death-ligand-1 (PD-L1) expression is crucial for optimizing treatment strategies involving immune checkpoint inhibitors. However, the role of intratumoral metabolic heterogeneity specifically derived from 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) images in predicting PD-L1 expression in patients with newly diagnosed non-small cell lung cancer (NSCLC) remains unexplored. Here, we investigated the association between FDG PET texture features and PD-L1 expression by retrospectively analyzing the data of patients newly diagnosed with NSCLC who underwent FDG PET/CT scans and PD-L1 immunohistochemical staining before treatment. Methods: Patients were categorized based on their tumor proportion scores (TPSs) into negative-, low-, and high-PD-L1 expression groups. We computed the maximum standardized uptake value and 31 texture features for the primary tumor from PET images and compared differences in parameters among the groups. Results: Of the 83 patients, 12, 45, and 26 were assigned to the negative-, low-, and high-PD-L1 expression groups, respectively. Six specific texture features (low gray-level run emphasis, short-run low gray-level emphasis, long-run high gray-level emphasis, low gray-level zone emphasis, high gray-level zone emphasis, and short-zone low gray-level emphasis) helped distinguish among all possible combinations. Conclusions: Our findings revealed that FDG PET texture features are potential imaging biomarkers for predicting PD-L1 expression in patients newly diagnosed with NSCLC.

暂无摘要。

Pulmonary carcinosarcomas (PCS) are uncommon and aggressive malignant tumors with epithelial and mesenchymal components and have a worse prognosis than other non-small-cell lung cancers. Metastases of non-thyroidal malignancies to the thyroid are rare. We reported a unique case of isolated thyroidal metastasis of PCS and discussed 18F-fluorodeoxyglucose (18F-FDG) positivity in incidentally found thyroid nodules on 18F-FDG positron emission tomography scan.
Pulmoner karsinosarkomlar (PCS), epitelyal ve mezenkimal bileşenleri olan ve diğer küçük hücreli dışı akciğer kanserlerinden daha kötü prognoza sahip, nadir görülen ve agresif malign tümörlerdir. Tiroid dışı malignitelerin tiroid metastazları nadirdir. PCS’nin oldukça benzersiz bir izole tiroid metastazı olgusunu bildirdik ve 18F-florodeoksiglikoz (18F-FDG) pozitron emisyon tomografi taramasında tesadüfen bulunan tiroid nodüllerindeki 18F-FDG pozitifliğini tartıştık.

Primitive neuroectodermal tumors (PNETs) are rare and aggressive members of the small round cell carcinoma family. Generally, PNETs are classified into two main groups: PNETs of the central nervous system and PNETs of the peripheral nervous system. Herein, we report the therapy response assessment of a rare case of isolated cardiac PNET using 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) imaging. Given that physiological cardiac FDG uptake is typically observed, assessing FDG avid lesions in the myocardium presents a challenge for FDG PET/CT. This case holds significance because of the rarity of the disease and the challenging nature of the site for FDG PET/CT imaging.
Primitif nöroektodermal tümörler (PNET) küçük yuvarlak hücreli tümörler ailesinin nadir görülen ve agresif bir üyesidir. PNET’ler genellikle santral sinir sisteminin PNET’leri ve periferik sinir sisteminin PNET’leri olmak üzere iki ana grupta değerlendirilmektedir. Burada, nadir görülen bir izole kardiyak PNET olgusunda tedavi yanıtının 18F-FDG pozitron emisyon tomografisi/bilgisayarlı tomografi (PET/BT) ile değerlendirmesi sunulmuştur. Fizyolojik kardiyak FDG tutulumu göz önünde bulundurulduğunda, miyokarddaki FDG tutan lezyonların değerlendirilmesi FDG PET/BT için zorluk oluşturmaktadır. Bu olgu, hastalığın nadirliği ve FDG PET/BT ile değerlendirilmesi için zorlu doğası nedeniyle önem taşımaktadır.

While extranodal involvement of diffuse large B-cell lymphoma (DLBCL) is common, skeletal muscle involvement is extremely rare. Isolated skeletal muscle involvement in lymphoma is even rarer. We present here the case of a 26-year-old woman, who was diagnosed to have a solitary isolated skeletal muscle relapse of DLBCL on surveillance 18F-fluorodeoxyglucose positron emission tomography-computed tomography, after completing first-line treatment, that was subsequently confirmed with biopsy.