Search Results (1,201)

¹⁸F-fluorodeoxyglucose (FDG) PET/CT is widely used for the evaluation of pulmonary lesions but lacks specificity, as increased FDG uptake is frequently observed in inflammatory and reparative processes. This limitation may lead to false-positive interpretations and unnecessary surgical resections. This study aimed to evaluate the immunohistochemical expression of integrin α_vβ₆ in 18 surgically resected pulmonary lesions that were falsely classified as malignant on FDG PET/CT, in order to find out if ⁶⁸Ga-Trivehexin PET/CT could have superior preoperative diagnostic specificity. Histopathological examination classified all lesions as non-neoplastic inflammatory processes of varying etiologies. Integrin α_vβ₆ expression was detected in all immunohistochemically examined tissue specimens (18/18 cases (100%)), with moderate membranous overexpression in 2/18 cases (11.11%) and strong membranous overexpression in 16/18 cases (88.89%) observed in the alveolar and bronchial epithelium of inflammatory lung lesions. Our findings indicate that integrin α_vβ₆ is upregulated not only in neoplastic lung tissue but also in inflammatory lesions, suggesting that integrin α_vβ₆ may have limited specificity for distinguishing primary neoplastic from inflammatory pulmonary lesions when used alone. Its interpretation requires integration with other clinical imaging modalities and histopathological data. Full article

Background: Post-treatment evaluation of residual neck disease in head and neck squamous cell carcinoma (HNSCC) is challenging because of treatment-related changes and biological differences between HPV-positive and HPV-negative tumors. Methods: We performed a prospective single-center study of 58 node-positive HNSCC patients treated with definitive chemoradiotherapy (CRT) followed by 18F-FDG PET/CT. PET-positive patients underwent neck dissection, while PET-negative patients were followed clinically for at least two years. Diagnostic performance was analyzed by p16 status. Results: PET/CT showed high overall accuracy (sensitivity 94%, specificity 83%, PPV 70%, NPV 97%). In p16-negative cases, sensitivity was 93%, specificity 80%, PPV 81%, and NPV 92%. In p16-positive cases, sensitivity and NPV reached 100%, but PPV was only 43%, indicating frequent false positives. Residual disease requiring neck dissection was associated with significantly worse survival (p = 0.008). Conclusions: PET/CT is reliable for post-treatment assessment, especially in p16-negative HNSCC. In p16-positive cases, careful interpretation and standardized PET/CT criteria are needed to reduce false positives and avoid unnecessary surgery. Full article

We report a diagnostically challenging case of a 79-year-old man who presented with mediastinal lymphadenopathy, hepatosplenomegaly, and renal enlargement, raising suspicion for clinical lymphoma. However, the histological evaluation of a submandibular gland excision revealed fibrosis, a dense IgG4-positive plasma cell infiltrate (>100/HPF), and an IgG4:IgG ratio > 40%, supportive of IgG4-related disease (IgG4-RD) in the appropriate clinicopathologic context. This case illustrates an important but well-recognised diagnostic pitfall in which IgG4-RD may clinically and radiologically mimic lymphoma. PET-CT demonstrated multiorgan involvement with diffuse FDG uptake, but definitive diagnosis required the integration of clinical, radiologic, serologic, and pathologic findings. The patient’s laboratory profile, including hypocomplementemia and elevated inflammatory markers, supported the proliferative phenotype of IgG4-RD—recently proposed in the literature as a clinically distinct subgroup with systemic involvement and steroid responsiveness. Rather than representing a novel presentation, this case reinforces the importance of integrated assessment in distinguishing IgG4-RD from haematolymphoid malignancy. PET-CT served as a useful adjunct for identifying multiorgan disease and guiding diagnostic evaluation, but tissue evaluation remained essential to avoid misdiagnosis and inappropriate treatment. Recognition of this entity is vital to avoid misdiagnosis and inappropriate treatment. Full article

Background and Objectives: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a minimally invasive technique widely used for mediastinal staging and diagnosis in patients with lung cancer and extrathoracic malignancies. This study aimed to evaluate patient and procedural factors associated with malignant histopathological outcomes in individuals undergoing EBUS-TBNA for intrathoracic lymphadenopathy across three malignancy groups: primary lung cancer, extrathoracic solid organ malignancy, and hematological malignancy. Materials and Methods: This retrospective descriptive study included patients who underwent EBUS-TBNA at Ankara Bilkent City Hospital between March 2019 and December 2023. Demographic characteristics, histopathological findings, procedural details, additional sampling techniques, and imaging parameters, including FDG SUVmax values from pre-procedural PET-CT, were recorded. Histopathological outcomes were categorized as malignant or non-malignant. Binary and multinomial logistic regression analyses were performed to identify independent predictors of malignancy and to differentiate between malignancy groups and lung cancer subtypes. Results: A total of 776 patients underwent EBUS-TBNA, and 667 were included after excluding non-diagnostic samples. Malignancy was detected in 274 patients, including primary lung cancer (n = 213, 77.7%), extrathoracic malignancy (n = 43, 15.7%), and hematological malignancy (n = 18, 6.6%). Of the included patients, 426 (63.9%) were male; the median age was 63 (IQR = 16) years. Older age (OR = 1.03, 95% CI = 1.02–1.05, p < 0.001), male sex (OR = 2.05, 95% CI = 1.43–2.93, p < 0.001), and larger lymph node size (OR = 1.09, 95% CI = 1.06–1.11, p < 0.001) were independently associated with malignant outcomes. Younger age, female sex, and smaller lymph node size were associated with extrathoracic malignancy compared to primary lung cancer, while younger age was the only predictor of hematological malignancy. Larger lymph node size was inversely associated with adenocarcinoma and squamous cell carcinoma compared with small cell lung cancer. Conclusions: Older age, male sex, and larger lymph node size independently predict malignant EBUS-TBNA outcomes. Younger age and female sex favor extrathoracic malignancy, whereas small cell lung cancer is associated with more extensive nodal involvement. Additional bronchoscopic techniques may enhance diagnostic accuracy in selected patients. Full article

Background/Objectives: Fibroblast activation protein (FAP) has emerged as a promising target for oncologic molecular imaging due to its high expression in cancer-associated fibroblasts and low presence in healthy tissues. Among available FAP ligands, [⁶⁸Ga]Ga-FAPi-46 has shown rapid tumor accumulation, low background uptake, and broad tumor applicability. This study reports the successful translation of [⁶⁸Ga]Ga-FAPi-46 from preclinical development to routine clinical radiopharmacy practice, detailing automated synthesis, quality control performance, radiochemical stability, and the first clinical imaging results. Methods: Automated radiolabeling of FAPi-46 with gallium-68 was performed using a synthesis module. Quality control included radiochemical purity assessments by iTLC, SPE, and RP-HPLC (pH, appearance, endotoxin levels, and membrane integrity testing). Radiochemical stability was evaluated in saline (up to 6 h) and human serum (up to 90 min). In vitro characterization included the partition coefficient and serum protein binding determination. A clinical evaluation was conducted in a woman with newly diagnosed lung adenocarcinoma who underwent both [¹⁸F]FDG PET/CT and [⁶⁸Ga]Ga-FAPi-46 PET/CT. Results: Automated synthesis of [⁶⁸Ga]Ga-FAPi-46 achieved a high radiochemical yield (87.9 ± 1.3%) and radiochemical purity greater than 98%. All batches met release specifications for sterility, apyrogenicity, and physicochemical parameters. The radiotracer demonstrated high stability in saline and human serum, with radiochemical purity consistently above 95% at all evaluated time points. The compound showed a hydrophilic profile (LogP = −3.32 ± 0.14) and 40–60% serum protein binding. Clinically, [⁶⁸Ga]Ga-FAPi-46 PET/CT provided superior lesion delineation compared to [¹⁸F]FDG, revealing additional mediastinal, supraclavicular, and brain metastases. Conclusions: [⁶⁸Ga]Ga-FAPi-46 can be reliably synthesized using automated procedures under routine radiopharmacy conditions, meeting regulatory quality standards and demonstrating excellent stability. Its enhanced lesion detectability compared with [¹⁸F]FDG in the first patient case supports its potential value for oncological staging and clinical implementation. Full article

Background and Objectives: Bladder cancer is one of the most common malignancies of the urinary tract and poses a significant clinical challenge due to its biological heterogeneity and high rates of recurrence and progression. Urothelial carcinoma represents the predominant histological subtype, ranging from non-muscle-invasive disease with relatively favorable outcomes to aggressive muscle-invasive and metastatic forms associated with poor prognosis. Accurate diagnosis, staging, prognostic stratification, and assessment of treatment response are therefore essential for optimal patient management. The objective of this review is to summarize and critically evaluate the current evidence on the role of positron emission tomography/computed tomography (PET/CT) in bladder cancer, with particular emphasis on [¹⁸F]FDG PET/CT and non-FDG radiotracers. Materials and Methods: A narrative review of the available literature was performed, focusing on clinical studies, review articles, and guideline documents addressing the use of PET/CT in bladder cancer. The literature search included articles published between 2000 and 2025, while earlier landmark studies were selectively included if considered historically important for understanding the development of PET/CT imaging in bladder cancer. The initial search yielded over 500 records; after screening titles and abstracts, more than 100 articles were selected for full-text evaluation. The analyzed evidence encompasses the clinical applications of [¹⁸F]FDG PET/CT and alternative radiotracers, including choline-, acetate-, methionine-, and sodium fluoride-based tracers, and fibroblast activation protein inhibitors (FAPI), across different stages of disease and clinical settings. Results: Conventional imaging modalities, such as computed tomography and magnetic resonance imaging, provide important anatomical information but remain limited in the evaluation of lymph node involvement, early metastatic disease, treatment response, and disease recurrence. Despite limitations related to physiological urinary excretion, [¹⁸F]FDG PET/CT has demonstrated clinical value in selected scenarios, particularly for staging, prognostic assessment, detection of recurrence, and response evaluation. To overcome FDG-related constraints, several non-FDG radiotracers have been investigated. Among these, FAPI PET/CT has emerged as a promising modality due to its ability to target the tumor stroma, potentially improving lesion detectability and tumor-to-background contrast. Conclusions: This review summarizes and critically evaluates current evidence on the role of PET/CT in bladder cancer, with a focus on [¹⁸F]FDG PET/CT and non-FDG radiotracers. The discussed studies highlight their applications in primary diagnosis, staging, prognostic assessment, detection of recurrence, and evaluation of treatment response, as well as their respective advantages and limitations. Furthermore, potential future directions for PET/CT imaging in clinical practice are outlined, emphasizing the need for further research to clarify the optimal use of established and emerging radiotracers. Full article

Background: Extracranial metastasis (EM) from glioblastoma (GB), IDH-wildtype (WHO CNS 2021 grade 4) is rare and often under-recognized, yet it has immediate implications for staging and management. We report a case series integrating advanced neuroimaging, whole-body imaging, and pathology/biomarkers to characterize imaging–pathology correlates of EM and highlight practical clinical triggers that should prompt systemic evaluation. Case presentation: We report three patients with adult-type, IDH-wildtype GB who developed EM confirmed by cytology/histology and/or concordant multimodality imaging. Brain MRI (1.5T/3T) demonstrated aggressive primary tumors with qualitative elevation of DSC-perfusion and frequent tumor–surface contact (dural, ependymal/leptomeningeal contact). Intratumoral susceptibility signal reached grade 3 where assessed. All patients underwent surgical resection followed by temozolomide-based chemoradiation; two received fotemustine and bevacizumab, and one underwent re-irradiation. EM presented with clinical triggers including severe axial/back pain, palpable cervical masses, and/or cytopenias. Initial EM sites were bone marrow/vertebrae (n = 1) and cervical lymph nodes (n = 2); staging revealed additional osseous disease in both nodal cases and a small pulmonary nodule in one. Nodal and osseous lesions were FDG-avid on 18F-FDG PET/CT. OLIG2-positive cytology confirmed cervical nodal metastases, and bone marrow aspiration with GFAP/OLIG2 positivity confirmed medullary infiltration. All tumors shared a molecular profile of TERT-promoter mutation, ATRX wild-type, TP53 mutation, and MGMT-promoter methylation. Despite attempts at second- and third-line therapies, disease progression was rapid, and all patients succumbed within 8–16 months of diagnosis. Discussion: This series underscores that EM can occur despite MGMT-promoter methylation and supports the concept of heterogeneous metastatic phenotypes in GB. Our cases reinforce that new axial/back pain or hematologic abnormalities may signal osseous or marrow involvement, and necrotic cervical lymphadenopathy in GB patients warrants dedicated imaging and tissue confirmation with glial markers. Integrating brain MRI features (high perfusion, surface contact, susceptibility burden) with FDG-PET/CT and targeted cytology/pathology can expedite diagnosis and inform multidisciplinary care. Conclusions: EM can arise despite MGMT-promoter methylation in IDH-wildtype GBM. Imaging red flags (high perfusion, surface contact, necrotic/FDG-avid cervical nodes) and clinical cues (axial pain, cytopenias, neck masses) should prompt early systemic staging (CT/PET-CT) and targeted tissue confirmation to advance management. Full article

Background/Objectives: Neoadjuvant therapy (NAT) is now central to the management of borderline resectable (BRPC) and locally advanced (LAPC) pancreatic ductal adenocarcinoma (PDAC). This narrative review summarizes contemporary evidence and guidelines from a surgical perspective, with emphasis on pretreatment classification, post-NAT selection for exploration, intraoperative vascular strategy, and postoperative management. Methods: We conducted a structured narrative review of randomized and prospective studies, high-quality observational cohorts, and major international guidelines published through 31 July 2025. Results: BRPC and LAPC remain primarily defined by vascular anatomy, but biologic and conditional factors are increasingly integrated into decision-making. NAT is the preferred initial strategy for BRPC and the standard induction approach for LAPC, with resection considered only in carefully selected responders. After NAT, contrast-enhanced CT combined with CA19-9 kinetics remains the core restaging platform, while FDG-PET, diffusion-weighted MRI, radiomics, and circulating biomarkers may serve as adjuncts in equivocal cases. Surgical exploration should be guided by physiologic recovery, the absence of metastatic progression, and multidisciplinary reassessment. Staging laparoscopy remains useful for detecting occult metastatic disease. Intraoperatively, vascular resection should be margin-driven rather than routine, with portal–mesenteric venous resection established in expert centers, whereas arterial resection remains highly selective. Periarterial divestment represents an artery-sparing alternative in selected cases. NAT does not appear to worsen short-term postoperative outcomes, but anticoagulation after venous reconstruction remains non-standardized. Conclusions: NAT has transformed BRPC/LAPC PDAC into a biology-gated, time-sequenced surgical pathway. Standardized reassessment, careful candidate selection, and the centralization of complex vascular procedures are essential to optimize outcomes. Full article

Background/Objectives: Routine liver biopsies play an important role in monitoring liver allografts but carry non-negligible risks. This pilot study assesses the feasibility of dynamic long-axial field-of-view (LAFOV) [¹⁸F]FDG PET/CT as a non-invasive alternative to biopsy. Methods: Liver transplant (LTx) recipients meeting the inclusion criteria of ≥10 months post-transplantation and scheduled routine biopsy were prospectively enrolled, along with healthy controls. All participants underwent dynamic LAFOV [¹⁸F]FDG PET/CT, followed by biopsy in LTx recipients, who were stratified by inflammatory severity using the BANFF score. Hepatic kinetic parameters (K1, k2, k3, k4) and SUVmean/SUVmax were compared using Mann–Whitney U tests. Correlations were assessed using Spearman’s rank correlation. A p-value < 0.05 was considered significant. Analyses were performed in RStudio (version 2024.12.10563). Results: Sixteen LTx recipients (mean age 48.6 years; seven female, nine male) and eight healthy controls (mean age 35.4 years; six female, two male) were included. Healthy controls had mean k3 and k4 values of 0.0037 min⁻¹ ± 0.0003 min⁻¹ and 0.0019 min⁻¹ ± 0.0011 min⁻¹, respectively. LTx recipients showed significantly higher k3 and k4 values, both when including and excluding patients with biopsy-confirmed inflammation. Descriptive comparisons between LTx recipients with and without significant inflammation (n = 3) showed no clear differences. Spearman analysis showed no significant correlations between the BANFF score and kinetic parameters. The strongest degree of correlation was found between BANFF score and k3, indicating a moderate positive but non-significant association (k3: rs = 0.396, p = 0.128). Conclusions: Elevated k3 and k4 values in LTx recipients were not explained by allograft inflammation, suggesting altered FDG kinetics post-transplant. These differences may confound [¹⁸F]FDG PET interpretation. Larger studies are needed to assess the clinical applicability of dynamic LAFOV [¹⁸F]FDG PET/CT. Full article

Background/Objectives: Psoriatic disease is a systemic inflammatory condition associated with increased cardiometabolic risk, but the impact of contemporary systemic therapies and narrowband ultraviolet B (NB-UVB) phototherapy on vascular and systemic inflammatory markers remains incompletely characterized. We aimed to systematically synthesize prospective evidence on treatment-associated changes in vascular inflammation and systemic inflammatory biomarkers in adults with moderate-to-severe psoriatic disease. Specifically, we evaluated changes assessed by 18F-FDG PET/CT imaging and circulating biomarkers following biologic therapies or NB-UVB phototherapy. Methods: We systematically searched MEDLINE, Embase, Web of Science, Scopus, and CENTRAL from inception to 31 January 2026 for prospective interventional and observational studies in adults with psoriasis or psoriatic arthritis treated with biologic agents targeting TNF-α, IL-12/23, IL-17, or IL-23, or with NB-UVB phototherapy. Eligible studies were required to report serial assessments of vascular inflammation by 18F-FDG PET/CT (typically aortic target-to-background ratio) and/or systemic inflammatory markers (high-sensitivity C-reactive protein, interleukin-6, TNF-α, GlycA, or hematologic indices such as the neutrophil-to-lymphocyte ratio) over at least 8 weeks of follow-up. We imposed no language restrictions and included only full-text, peer-reviewed prospective studies. Risk of bias was evaluated using RoB 2 for randomized trials and ROBINS-I for nonrandomized studies. Random-effects meta-analyses were prespecified for outcomes reported by at least two clinically comparable studies; however, because of substantial heterogeneity in reporting and methodology, effect estimates were summarized using a structured narrative synthesis. Results: Thirteen prospective studies (n ≈ 900 adults, published 2015–2025) met inclusion criteria, including four studies with serial 18F-FDG PET/CT imaging and one additional PET/CT study providing baseline observational data on vascular inflammation, as well as eight biomarker-focused prospective cohorts. Across randomized mechanistic trials and observational studies, biologic therapies reduced aortic target-to-background ratio by approximately 6–12% over 12–24 weeks (e.g., mean change from 2.42 to 2.18 with TNF-α inhibition and from 2.51 to 2.20 with IL-17 blockade), and no study reported worsening of PET-derived vascular indices under effective systemic treatment. Biologic and other systemic therapies produced concordant reductions in hs-CRP (typically by 30–50%), IL-6, TNF-α, GlycA, and blood-count-derived indices including neutrophil-to-lymphocyte ratio, with biomarker improvements frequently paralleling reductions in cutaneous disease activity and cardiometabolic risk markers. Two NB-UVB cohorts demonstrated significant hs-CRP reductions of roughly 20–30% and modulation of vitamin D-related inflammatory proteins, suggesting systemic anti-inflammatory effects, although these changes appeared less pronounced than with biologic therapy and were not accompanied by vascular imaging. Conclusions: Contemporary systemic psoriasis therapies, particularly biologic agents targeting the IL-23/Th17 axis and TNF-α, are associated with consistent reductions in aortic vascular inflammation and broad improvements in systemic inflammatory biomarkers, whereas NB-UVB phototherapy confers more modest but measurable systemic anti-inflammatory effects, although the current evidence does not allow differentiation between individual biologic classes in terms of magnitude of effect. Although reductions in vascular and systemic inflammatory markers were observed across therapies targeting TNF-α, IL-12/23, IL-17, and IL-23, the small number of mechanistic imaging studies and absence of head-to-head comparisons do not allow robust differentiation between biologic classes or support a uniform class effect. The convergence of imaging and biomarker data reinforces psoriasis as a clinically relevant model of inflammation-driven atherosclerosis and supports the concept that effective control of psoriatic inflammation may contribute to cardiovascular risk modification, highlighting the need for integrated cardiovascular risk assessment in routine care. However, the imaging evidence base remains limited to four small mechanistic PET/CT studies with relatively short follow-up, which constrains the strength and generalizability of conclusions regarding vascular inflammation. Larger, adequately powered, event-driven prospective trials with standardized imaging and biomarker endpoints are needed to determine whether these vascular and systemic anti-inflammatory effects translate into reduced cardiovascular events in psoriatic disease; because of methodological and reporting heterogeneity across the 13 included studies, these conclusions are based on a structured narrative synthesis rather than a formal quantitative meta-analysis. PROSPERO registration number: CRD420261296646. Full article

Extramedullary haematopoiesis (EMH) refers to haematopoietic proliferation outside the bone marrow, most often arising as a compensatory response to ineffective marrow function in chronic anaemias and myeloid neoplasms, particularly myelofibrosis and other myeloproliferative neoplasms. While the liver and spleen are typical sites, renal involvement remains particularly uncommon and may mimic infiltrative malignancy or infection on cross-sectional imaging. We report a 35-year-old woman with biopsy-proven grade 2 myelofibrosis who presented with constitutional symptoms, namely asthenia, progressive weight loss, and intermittent fever, in the setting of pancytopenia. Contrast-enhanced CT demonstrated bilateral thoracic paravertebral and presacral soft-tissue masses, with left peripelvic/pelvicalyceal infiltration, raising concern for infiltrative malignancy or infection. [¹⁸F]-FDG-PET/CT showed low-grade uptake in the paravertebral and presacral lesions, while the renal lesion remained indeterminate because of adjacent urinary tracer activity. Given the haemorrhagic risk of renal biopsy in a cytopenic patient, [^99mTc]-sulphur colloid scintigraphy with SPECT/CT was performed and demonstrated concordant tracer uptake in all lesions, supporting multifocal EMH. After disease-directed treatment, follow-up CT at 12 months showed marked regression of the renal and other EMH lesions. This case highlights renal peripelvic EMH as a rare imaging pitfall and underscores the value of multimodality imaging when biopsy is high risk. Full article

Background/Objectives: Novel hotspot displacement radiomic features (normalized hotspot-to-centroid distance [NHOC]/normalized hotspot-to-perimeter distance [NHOP]) are robust against image resampling and spatial resolution variations. However, their reproducibility under respiratory motion remains unvalidated. This study aimed to evaluate the reproducibility, reliability, and survival prognostic value of NHOC/NHOP features in thoracic ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) images with and without respiratory motion correction and to determine whether these features maintain stability and predictive performance for overall survival (OS) compared with respiratory-stable reference features. Methods: We analyzed 138 patients (203 lesions) who underwent ¹⁸F-FDG PET/CT with and without data-driven respiratory gating. Reproducibility and reliability were assessed using the coefficient of variation (CoV) and intraclass correlation coefficient (ICC), respectively. OS prediction was evaluated using Cox regression and concordance index (c-index) analyses. Results: Except for NHOCmax and NHOPpeak, which showed ICC values of 0.782 and 0.93, respectively, the novel morphological features generally exhibited poor reproducibility and moderate reliability (CoV > 20% and ICC < 0.75). In contrast, reference features (entropy-based and sphericity) demonstrated excellent robustness. Motion-corrected NHOCmax showed significant OS prediction for both spatially resampled and non-resampled images. No significant differences in c-indices were observed between motion-corrected and non-corrected features. Conclusions: The marked sensitivity of novel hotspot-displacement features to respiratory motion substantially limits their clinical applicability in thoracic disease. To ensure reproducibility and generalizability in future research, prioritizing inherently robust radiomic parameters, such as entropy-based features, is strongly recommended. Full article

Testicular metabolism can be non-invasively assessed using FDG-PET/CT, which provides insights into physiological and age-related changes. Understanding normal testicular FDG uptake is essential to distinguish between benign variation and pathological findings. In this retrospective study, 80 men (mean age: 54.7 years, range: 26–79) who underwent PET/CT for lung nodule evaluation were analyzed, excluding individuals with testicular disease, prior surgery, or elevated blood glucose (>180 mg/dL). FDG uptake (SUV_mean) and testicular volume were measured for each testis, and correlations with age, blood glucose, and volume were assessed using standard statistical methods. The mean testicular SUV_mean was 2.62 ± 0.50, showing a significant negative correlation with age and a weak positive correlation with testicular volume. After adjusting for volume, the negative association with age persisted, while no significant relationship with blood glucose was observed. These findings indicate that physiological testicular FDG uptake gradually declines with age, reflecting both metabolic and structural alterations. Recognizing these normal patterns is critical for accurate PET/CT interpretation and reducing the risk of false-positive findings. Full article

Sutureless aortic bioprostheses have become an established alternative for surgical aortic valve replacement, particularly in elderly and high-risk patients. The Perceval (Livanova) valve, the most widely studied sutureless device, offers favorable hemodynamic performance and reduced operative times but introduces specific challenges when prosthetic valve endocarditis (PVE) occurs. Although the incidence of Perceval PVE is low and comparable to that of conventional bioprostheses, this complication is associated with substantial morbidity and mortality. Diagnosis is often complex due to acoustic shadowing on echocardiography, making multimodality imaging with transesophageal echocardiography, cardiac computed tomography, and [18F]-FDG PET/CT essential. Microbiological profiles resemble those of other biological prostheses, but perivalvular extension and early mechanical instability are frequent. Management follows general PVE principles but often requires early surgical intervention because of the valve’s reliance on radial fixation. This review summarizes current evidence on epidemiology, microbiology, diagnostic strategies, treatment, and prognosis of endocarditis involving the Perceval valve, and identifies areas for future research. Full article

Background and Clinical Significance: Diffuse Large B-Cell Lymphoma (DLBCL) is a morphologically and molecularly heterogeneous lymphoproliferative disorder that originates from a clonal B-cell ancestor. Patients usually present with rapidly enlarging lymph nodes or mass(es) at single or multiple sites. Generally, 18F-Fluorodeoxyglucose (18F-FDG) positron emission tomography with computed tomography (PET-CT) is performed post-treatment to evaluate remission status, especially in radiologically residual tumors. Myofibroblastoma (MFB) is a benign mesenchymal tumor of the mammary stroma composed of fibroblasts and myofibroblasts. These entities do not often present concurrently. Case presentation: The patient was an 80-year-old man with a history of stage IV-BS Diffuse Large B-Cell Lymphoma (DLBCL) with a high-risk International Prognostic Index (IPI). The patient underwent treatment with a six-cycle R-CHOP regimen. Immediately after the last cycle, an 18F-Fluorodeoxyglucose (18F-FDG) positron emission tomography with computed tomography (PET-CT) scan revealed a nodular solid lesion with a faintly increased metabolic standardized uptake value (SUVmax) of 3 in the upper outer quadrant of his left breast. A biopsy of the breast lesion was performed, and it revealed a benign mesenchymal tumor, specifically a Myofibroblastoma. The patient has not presented any symptoms or complications since surgery (12 months) and remains in complete remission (CR). Conclusions: Given the potential diagnostic pitfalls and therapeutic implications of residual tumors in the context of DLBCL, a conscientious evaluation by a multidisciplinary team (MDT) is highly recommended. Full article