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.

Polyneuropathy, organomegaly, endocrinopathy, M protein elevation, and skin changes (POEMS) syndrome is one of the rare paraneoplastic disorders of the multiorgan association whose initialism describes the principal clinical features as polyneuropathy, organomegaly, endocrinopathy, M-protein elevation, and skin changes caused by an underlying plasma cell disorder, one of the major diagnostic criteria for which is the presence of an osseous lesion. We present a case of POEMS syndrome with nearly all signs and symptoms on clinical and hematological examinations, which was further investigated with MRI of the whole spine and 18F-fluorodeoxyglucose positron emission tomography/computed tomography scan, as the latter is a very useful imaging modality for evaluation of any paraneoplastic syndromes, including myeloproliferative disorders such as plasmacytoma or multiple myeloma, and lymphoproliferative or other malignancies.

Pulmonary enteric adenocarcinoma (PEAC) is an extremely rare variant of lung adenocarcinoma characterized by pathological features similar to those of colorectal adenocarcinoma. It is mostly observed on computed tomography (CT) and positron emission tomography (PET)/CT as solitary or multiple nodules/masses in the lung. It tends to grow rapidly and is difficult to distinguish from lung metastatic colorectal cancer. Herein, we have presented a case of PEAC with special imaging findings.
A chest CT scan of a 72-year-old man with suspected chronic pneumonia revealed a well-defined consolidation in the upper lobe of the left lung. The lesion was slightly enlarged at the 9-month follow-up, and low FDG accumulation was subsequently observed using 18F-fluorodeoxyglucose (18F-FDG) PET/CT scans. The patient was later diagnosed with PEAC through percutaneous lung biopsy.
Our case has demonstrated specific imaging findings of PEAC.

UNASSIGNED: The purpose of this study was to compare the diagnostic efficacy of PET/CT-aided CT-guided and routine CT-guided transthoracic needle biopsy for lung lesions.
UNASSIGNED: A total of 458 patients with suspicious lung lesions were referred for CT-guided biopsy, with 227 patients assigned to the PET/CT group and 231 patients assigned to the CT group. The clinical characteristics and diagnostic yield were compared between the two groups. Furthermore, conducting subgroup analysis to evaluate the differences of diagnostic success or failure between the two groups.
UNASSIGNED: The sensitivity and diagnostic accuracy rate differed significantly (P = 0.035, P = 0.048). In the PET/CT group, the values were 95.7% and 96.3%, respectively, while in the CT group, they were 90.1% and 91.9%. When considering non-diagnostic cases, the overall diagnostic success rate increased markedly in PET/CT group (93.0% vs. 83.1%, P = 0.001). In our subgroup analysis, the PET/CT group demonstrated superiority in detecting lesions larger than 3 cm (OR, 4.81; 95CI%, 2.03 - 11.36), while showing a moderate effect in lesions smaller than 3 cm (OR, 1.09; 95CI%, 0.42 - 2.81). Significant effect modification was observed in large lesions in the PET/CT group (P for interaction = 0.023).
UNASSIGNED: 18F-FDG-PET/CT enhances the diagnostic efficacy of CT-guided transthoracic needle biopsy for lung lesions, and the incremental value can be modified by lesion size, particularly when the diameter is larger than 3 cm.