Introduction: A negative computed tomography (CT) scan does not preclude an insulinoma, as small lesions frequently remain undetected on conventional imaging. This case highlights the indispensable role of endoscopic ultrasound (EUS)— not just for localizing occult tumors, but as a definitive, minimally invasive therapeutic alternative to high-risk surgical resection. Case: A 39-year-old female with underlying hypertension presented with a 5-month history of predominantly fasting hypoglycemia (glucose <3.0 mmol/L) and neuroglycopenic symptoms, fulfilling Whipple’s triad. A supervised 72-hour fast confirmed endogenous hyperinsulinemic hypoglycemia at 31 hours, with a nadir glucose of 1.4 mmol/L, insulin 116 pmol/L, and C-peptide 821 pmol/L. Notably, contrastenhanced CT of the pancreas was reported as normal. To overcome this, EUS was performed, successfully identifying a hidden 19 × 18 mm lesion in the head of the pancreas, intimately abutting the main pancreatic duct. Despite medical therapy with diazoxide and strict dietary modifications, her hypoglycemia remained refractory. Given the tumor’s proximity to the main pancreatic duct, surgical enucleation carried a prohibitively high risk of complications. Consequently, she underwent EUS-guided radiofrequency ablation (RFA). Immediate post-procedure outcomes demonstrated near-complete resolution of the hypoglycemic episodes. Diazoxide was subsequently stopped. Outpatient continuous glucose monitoring confirmed sustained normoglycemia and marked symptom resolution, with no procedure-related complications. Conclusion The absence of a pancreatic lesion on CT demands persistent clinical suspicion in cases of biochemically proven hypoglycemia. EUS remains paramount for detecting occult lesions missed by standard imaging. Importantly, EUSRFA serves as a highly effective, tissue-sparing alternative to surgical resection for insulinomas, especially when conventional surgery poses prohibitive anatomical risks.
Insulinoma ; Tomography, X-Ray Computed

Introduction: Insulinoma is a rare functioning pancreatic neuroendocrine tumor and the most common cause of endogenous hyperinsulinemic hypoglycemia. Although biochemical confirmation is usually straightforward, tumor localization may be difficult when lesions are small and not detected on conventional cross-sectional imaging. In such cases, endoscopic ultrasound (EUS) plays an important role in identifying occult lesions and facilitating definitive treatment. Case: A 52-year-old female was admitted in April 2025 with recurrent seizures secondary to hypoglycemia for 3 years, with increasing frequency over time. She fulfilled Whipple’s triad, with documented capillary glucose of 1.8 mmol/L during an episode and symptom resolution following glucose administration. A supervised prolonged fasting test confirmed endogenous hyperinsulinemic hypoglycemia, with plasma glucose 1.4 mmol/L, insulin 122 pmol/L, and C-peptide 1,010 pmol/L. Short Synacthen test demonstrated adequate adrenal reserve. Due to persistent hypoglycemia, she required high-dose diazoxide. Contrast-enhanced computed tomography abdomen did not reveal a pancreatic lesion but incidentally detected a right ovarian teratoma. She underwent total abdominal hysterectomy and bilateral salpingo-oophorectomy in June 2025, with histopathology confirming a mature cystic teratoma without malignancy. However, hypoglycemic episodes persisted. Further evaluation with EUS in July 2025 identified a highly vascular isoechoic 8 × 8 mm lesion in the pancreatic body. Fine-needle biopsy confirmed a well-differentiated neuroendocrine tumor (WHO grade 1) with Ki-67 index of 2%. She subsequently underwent EUSguided radiofrequency ablation in August 2025. Follow-up EUS in December 2025 showed post-ablation change, and her hypoglycemic episodes resolved completely, allowing diazoxide to be discontinued. Conclusion This case highlights the diagnostic challenge of occult insulinoma in the presence of negative conventional imaging. EUS was pivotal for tumor localization and tissue diagnosis, while EUS-guided radiofrequency ablation provided effective minimally invasive treatment in a carefully selected patient.
Insulinoma ; Tomography, X-Ray Computed

A 39-year-old male patient was admitted to hospital with abdominal distension, unconsciousness, and anuria. Head computed tomography (CT) showed subarachnoid hemorrhage and diffuse cerebral edema. The high-density area of contrast accumulation region in the high-density CT plaque was 38 HU, and the preliminary diagnosis was SAH, incomplete intestinal obstruction, and sepsis caused by acute cerebrovascular disease. After admission, the patient displayed upturned eyes, limb convulsions, serum procalcitonin level exceeding 100 ng/mL, low blood pressure and septic shock. Imipenem was given for intensive anti-infection therapy. After treatment, procalcitonin levels showed a slow decline, renal function, and intra-abdominal pressure returned to normal, urine volume gradually increased, but platelets still showed a downward trend. Lumbar puncture showed colorless and clear cerebrospinal fluid, and the biochemical and routine results of cerebrospinal fluid were normal. SAH and intracranial infection were excluded, and it was considered that the head CT showed pseudo-subarachnoid hemorrhage. On the 3rd day of admission, laparoscopic exploratory laparotomy+appendectomy+abdominal drainage under general anesthesia were performed. During surgery, purulent gangrene in the appendix was found, with pus adhering to the surface of the intestines and a large amount of pus present in the abdominal cavity. Rhabdomyolysis syndrome developed after surgery. After continuous renal replacement therapy, the indicators gradually returned to normal. The patient was conscious, and the head CT results were normal. The patient was discharged from the hospital on the 19th day after surgery, and no special discomfort and abdominal pain and distension occurred during the 3-month follow-up.
Humans ; Male ; Adult ; Tomography, X-Ray Computed ; Sepsis/diagnostic imaging* ; Multiple Organ Failure/etiology* ; Subarachnoid Hemorrhage/complications*

OBJECTIVE: To investigate the prognostic value of ¹⁸ F-deoxyglucose (FDG) PET/CT metabolic parameters combined with clinicopathological features for newly diagnosed diffuse large B-cell lymphoma (DLBCL) before treatment, and analyze the relationship between tumor metabolic volume (MTV), total lesion glycolysis (TLG) and clinicopathological features. METHODS: The clinical data of 120 patients with pathologically confirmed DLBCL were retrospectively analyzed and ¹⁸F-FDG PET/CT was performed 1 week before treatment. The metabolic parameters including SUVmax, SUVmean, tumor-to-blood standardized uptake value ratio (TBR), tumor-to-liver standardized uptake value ratio (TLR) were obtained. MTV and TLG of the lesions were obtained with 41% of SUVmax as the threshold, and the correlation of MTV and TLG with clinicopathological features were analyzed. Progression-free survival (PFS) was calculated by follow-up for 6-153 months. Receiver operating characteristic (ROC) curve, chi-square test, Kaplan-Meier test, log-rank test and Cox proportional hazards model were used to analyze the date. RESULTS: The optimum cut-off values of the SUVmax, MTV, TLG, TBR and TLR for predicting tumor progression were 22.25, 256.05, 5 232.67, 12.97 and 10.60, respectively. The patients were divided into two groups according to the above cut-off values, respectively. Kaplan-Meier survival analysis showed that there were statistically significant differences in PFS between the two group (all P <0.05). The MTV and TLG values were correlated with NCCN-IPI score, Ann Arbor stage, serum lactate dehydrogenase level, and C-MYC, BCL-2, BCL-6 gene rearrangement (all P <0.05). Univariate analysis showed that NCCN-IPI score >3, C-MYC, BCL-2, BCL-6 gene rearrangement positive, SUVmax≥22.25, MTV≥256.05 cm³, TLG≥5 232.67 g and TBR≥12.97 were adverse factors for prognosis (HR: 1.949-5.759, all P <0.05). Multivariate Cox regression analysis showed that C-MYC, BCL-2 gene rearrangement positive and TLG≥5 232.67 g were all independent risk factors affecting PFS (HR: 4.660, 3.350, 4.031, all P <0.05). CONCLUSION The ¹⁸F-FDG PET/CT metabolic parameters SUVmax, MTV, TLG, TBR and TLR can be used as important indicators to predict PFS of DLBCL patients, and combining clinicopathological features can better predict the prognosis of patients.
Humans ; Lymphoma, Large B-Cell, Diffuse/diagnosis* ; Fluorodeoxyglucose F18 ; Positron Emission Tomography Computed Tomography ; Prognosis ; Retrospective Studies ; Male ; Female ; Middle Aged ; Adult

OBJECTIVE: To analyze the correlation between baseline ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) and circulating tumor DNA (ctDNA) parameters in diffuse large B-cell lymphoma (DLBCL) and compare the value of the two methods in the prognosis assessment of DLBCL. METHODS: A total of 50 DLBCL patients confirmed by pathology, including 26 males and 24 females, with a median age of 55.5(43.5, 64.0) years from August 2018 to April 2021 were retrospectively analyzed. PET/CT parameters, including maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), total lesion glycolysis (TLG), ctDNA parameters, including mutation number, mutation gene number, mean variant allele frequency (meanVAF), and clinical data of patients were collected. The relationship between PET/CT, ctDNA parameters and patient clinical features was analyzed, as well as the correlation between PET/CT and ctDNA parameters. The diagnostic efficacy of PET/CT and ctDNA parameters was compared. Patients were followed up for 36-69 months. Progression-free survival (PFS) was calculated, and survival analysis was performed. RESULTS: PET/CT parameters all had good correlation with ctDNA parameters, among which MTV was moderately correlated with mutation number, mutation gene number, and meanVAF (r_s=0.72, 0.64, 0.71), TLG was strongly correlated with mutation number (r_s=0.83) and moderately correlated with mutation gene number and mean VAF (r_s=0.72, 0.79), while SUVmax was weakly correlated with mutation number, mutation gene number and meanVAF (r_s=0.47, 0.46, 0.47). PET/CT parameters and ctDNA parameters showed no statistically significant differences in predicting the prognosis of DLBCL and area under the curve (AUC) of receiver operating characteristic (ROC) (P >0.05). However, the specificity of MTV and TLG in predicting prognosis of 1-, 2- and 3-year PFS was better than that of meanVAF (all P < 0.05), while the sensitivity of meanVAF in predicting prognosis of 1-, 2- and 3-year PFS was better than that of MTV (all P < 0.05). The optimal cut-off values of SUVmax, MTV, TLG, mutation number, mutation gene number and meanVAF in predicting tumor progression were obtained using ROC curve analysis. Patients were divided into high and low expression groups according to the cut-off values and survival analysis was performed. The results of survival analysis showed that there were statistically significant differences in PFS between the high and low expression groups (all P < 0.05). CONCLUSION Baseline ¹⁸F-FDG PET/CT and ctDNA parameters can both predict the prognosis of DLBCL, and are equally valuable in the evaluation of DLBCL prognosis.
Humans ; Lymphoma, Large B-Cell, Diffuse/diagnosis* ; Positron Emission Tomography Computed Tomography ; Fluorodeoxyglucose F18 ; Middle Aged ; Prognosis ; Female ; Male ; Circulating Tumor DNA ; Retrospective Studies ; Adult ; Mutation

Accurate staging is the fundamental basis for the treatment and prognosis of non-small cell lung cancer (NSCLC), and whether the tumor involves the pleura or chest wall is a critical aspect in assessing the staging of peripheral lung cancer. Imaging techniques such as computed tomography (CT), magnetic resonance imaging (MRI), ultrasound (US) and positron emission tomography (PET) are widely used to determine pleural invasion in NSCLC. There has been an increasing number of studies evaluating whether NSCLC invades the pleura and the extent of such invasion. This article provides a review of the staging and the imaging diagnostic criteria of pleural invasion, aiming to offer references for peers in the precise diagnosis of pleural or chest wall invasion.
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Humans ; Carcinoma, Non-Small-Cell Lung/diagnosis* ; Lung Neoplasms/diagnosis* ; Thoracic Wall/diagnostic imaging* ; Pleura/diagnostic imaging* ; Neoplasm Invasiveness ; Tomography, X-Ray Computed

Lung cancer is still one of the most common malignant tumors in the world. With the increase of its incidence and the development of medical technology, the overall survival of lung cancer patients has significantly extended compared to before. The incidence of brain and meningeal metastases from lung cancer has also been rising year by year, but patients with brain and meningeal metastases from lung cancer have a poor prognosis and a very high mortality rate, and the diagnosis is mainly based on computed tomography (CT), magnetic resonance imaging (MRI) and other imaging examinations. However, the imaging features are diverse and the specificity is low, which makes it easy to be misdiagnosed and missed. Therefore, accurately identifying brain and meningeal metastases and timely targeted treatment is crucial for improving patient prognosis. This paper analyzed the diagnosis and treatment of a case of lung cancer with no obvious recurrence and metastasis in nearly 7-year long-term follow-up after radical lung cancer surgery, but the patient with abnormal behavior, impaired consciousness and epilepsy in the past 5 months, and multiple punctate calcifications in the brain found by head CT and MRI. This paper consider that the patient's mental and behavioral symptoms were caused by brain and meningeal metastasis of lung cancer after excluding infectious disease and ineffective treatment of autoimmune encephalitis, and further pathological biopsy and genetic detection confirmed the diagnosis of metastatic lung adenocarcinoma with epidermal growth factor receptor (EGFR) L858R gene mutation, and the patient's symptoms were significantly improved after targeted therapy by Osimertinib. This paper also searched the relevant literatures of brain calcifications in databases such as China National Knowledge Infrastructure (CNKI), Wanfang, UpToDate, PubMed, etc., and found that intracerebral calcifications exist in a variety of diseases, including infectious, genetic and neurodegenerative diseases, vascular diseases, metabolic diseases and tumors. However, brain calcification in brain and meningeal metastases are often underestimated, and the consequent risk is misdiagnosis and delayed treatment. Therefore, brain and meningeal metastases manifested as brain calcification should not be ignored in patients with a history of previous tumors.
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Humans ; Lung Neoplasms/pathology* ; Brain Neoplasms/diagnostic imaging* ; Meningeal Neoplasms/diagnostic imaging* ; Calcinosis/diagnostic imaging* ; Male ; Middle Aged ; Tomography, X-Ray Computed ; Magnetic Resonance Imaging

BACKGROUND: Lung cancer is one of the most common malignant tumors worldwide and a major cause of cancer-related deaths. Early-stage lung cancer is often manifested as pulmonary nodules, and accurate assessment of the malignancy risk is crucial for prolonging survival and avoiding overtreatment. This study aims to construct a model based on image feature parameters automatically extracted by artificial intelligence (AI) to evaluate its effectiveness in predicting the malignancy of part-solid nodule (PSN). METHODS: This retrospective study analyzed 229 PSN from 222 patients who underwent pulmonary nodule resection at Lanzhou University Second Hospital between October 2020 and February 2025. According to pathological results, 45 cases of benign lesions and precursor glandular lesion were categorized into the non-malignant group, and 184 cases of pulmonary malignancies were categorized into the malignant group. All patients underwent preoperative chest computed tomography (CT), and AI software was used to extract imaging feature parameters. Univariate analysis was used to screen significant variables; variance inflation factor (VIF) was calculated to exclude highly collinear variables, and LASSO regression was further applied to identify key features. Multivariate Logistic regression was used to determine independent risk factors. Based on the selected variables, five models were constructed: Logistic regression, random forest, XGBoost, LightGBM, and support vector machine (SVM). Receiver operating characteristic (ROC) curves were used to assess the performance of the models. RESULTS: The independent risk factors for the malignancy of PSN include roughness (ngtdm), dependence variance (gldm), and short run low gray-level emphasis (glrlm). Logistic regression achieved area under the curves ( AUCs) of 0.86 and 0.89 in the training and testing sets, respectively, showing good performance. XGBoost had AUCs of 0.78 and 0.77, respectively, demonstrating relatively balanced performance, but with lower accuracy. SVM showed an AUC of 0.93 in the training set, which decreased to 0.80 in the testing set, indicating overfitting. LightGBM performed excellently in the training set with an AUC of 0.94, but its performance declined in the testing set, with an AUC of 0.88. In contrast, random forest demonstrated stable performance in both the training and testing sets, with AUCs of 0.89 and 0.91, respectively, exhibiting high stability and excellent generalizability. CONCLUSIONS The random forest model constructed based on independent risk factors demonstrated the best performance in predicting the malignancy of PSN and could provide effective auxiliary predictions for clinicians, supporting individualized treatment decisions.
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Humans ; Male ; Female ; Lung Neoplasms/pathology* ; Middle Aged ; Retrospective Studies ; Artificial Intelligence ; Aged ; Tomography, X-Ray Computed ; Adult ; Solitary Pulmonary Nodule/diagnostic imaging* ; ROC Curve

In recent years, the widespread application of chest computed tomography (CT) screening has led to a significant increase in the detection rate of pulmonary nodules. As a critical diagnostic tool for early-stage lung cancer, video-assisted thoracic surgery (VATS) has emerged as the preferred therapeutic approach for pulmonary nodules. Clinical evidence demonstrates that precise preoperative localization significantly enhances surgical success rates (reducing conversion to thoracotomy), minimizes complications, and shortens operation time. This comprehensive review systematically evaluates six cutting-edge localization techniques: percutaneous puncture-assisted localization, electromagnetic navigation bronchoscopy (ENB) localization, 3D-printed auxiliary localization, basin-analysis-based localization, robotic navigation system localization, and mixed reality (MR)-guided localization. By critically analyzing their operational principles, efficacy, safety profiles, and clinical applicability, this paper aims to provide evidence-based recommendations for optimizing clinical decision-making in pulmonary nodule management.
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Humans ; Lung Neoplasms/diagnosis* ; Solitary Pulmonary Nodule/diagnostic imaging* ; Thoracic Surgery, Video-Assisted/methods* ; Multiple Pulmonary Nodules/diagnostic imaging* ; Tomography, X-Ray Computed

BACKGROUND: Lung adenocarcinoma is an important pathohistologic subtype of non-small cell lung cancer (NSCLC). Invasive non-mucinous pulmonary adenocarcinomas (INMA) tend to have a poor prognosis due to their significant heterogeneity and diverse histologic components. Establishing a histologic grading system for INMA is crucial for evaluating its malignancy. In 2021, the International Association for the Study of Lung Cancer (IASLC) proposed that a new histological grading system could better stratify the prognosis of INMA patients. The aim of this study was to establish a visualized nomogram model to predict INMA IASLC grading preoperatively by means of dual-energy computed tomography (DECT), fractal dimension (FD), clinical features and conventional CT parameters. METHODS: A total of 112 patients with INMA who underwent preoperative DECT were retrospectively enrolled from March 2021 to January 2025. Patients were categorized into low-intermediate grade and high grade groups based on IASLC grading. The clinical characteristics and conventional CT parameters, including baseline features, biochemical markers, and serum tumor markers, were collected. DECT-derived parameters, including iodine concentration (IC), effective atomic number (eff-Z), and normalized IC (NIC), were collected and determined as NIC ratio (NICr) and fractal dimension (FD). Univariate analysis was employed to compare differences in conventional characteristics and DECT parameters between the two groups. Variables demonstrating statistical significance were subsequently incorporated into a multivariate Logistic regression analysis. A nomogram model integrating clinical data, conventional CT parameters, and DECT parameters was developed to identify independent predictors for IASLC grading of INMA. The discriminatory performance of the model was evaluated using receiver operating characteristic (ROC) curve analysis. RESULTS: Multivariate analysis identified smoking history [odds ratio (OR)=2.848, P=0.041], lobulation sign (OR=2.163, P=0.004), air bronchogram (OR=7.833, P=0.005), eff-Z in arterial phase (OR=4.266, P<0.001), and IC in arterial phase (OR=1.290, P=0.012) as independent and significant predictors for IASLC grading of INMA. The nomogram model constructed based on these indicators demonstrated optimal predictive performance, achieving an area under the curve (AUC) of 0.804 (95%CI: 0.725-0.883), with specificity and sensitivity of 85.3% and 65.7%, respectively. CONCLUSIONS The nomogram model based on clinical features, imaging features and spectral CT parameters have a large potential for application in the preoperative noninvasive assessment of INMA IASLC grading.
Humans ; Nomograms ; Female ; Male ; Middle Aged ; Tomography, X-Ray Computed/methods* ; Lung Neoplasms/pathology* ; Aged ; Retrospective Studies ; Adenocarcinoma of Lung/pathology* ; Neoplasm Grading ; Adult