BACKGROUND: At present, biopsy is essential for the diagnosis of prostate cancer (PCa) before radical prostatectomy (RP). However, with the development of prostate-specific membrane antigen positron emission tomography/computed tomography (PSMA PET/CT) and multiparametric magnetic resonance imaging (mpMRI), it might be feasible to avoid biopsy before RP. Herein, we aimed to explore the feasibility of avoiding biopsy before RP in patients highly suspected of having PCa after assessment of PSMA PET/CT and mpMRI. METHODS: Between December 2017 and April 2022, 56 patients with maximum standardized uptake value (SUVmax) of ≥4 and Prostate Imaging Reporting and Data System (PI-RADS) ≥4 lesions who received RP without preoperative biopsy were enrolled from two tertiary hospitals. The consistency between clinical and pathological diagnoses was evaluated. Preoperative characteristics were compared among patients with different pathological types, T stages, International Society of Urological Pathology (ISUP) grades, and European Association of Urology (EAU) risk groups. RESULTS: Fifty-five (98%) patients were confirmed with PCa by pathology, including 49 (89%) with clinically significant prostate cancer (csPCa, defined as ISUP grade ≥2 malignancy). One patient was diagnosed with high-grade prostatic intraepithelial neoplasia (HGPIN). CsPCa patients, compared with clinically insignificant prostate cancer (cisPCa) and HGPIN patients, were associated with a higher level of prostate-specific antigen (22.9 ng/mL vs . 10.0 ng/mL, P = 0.032), a lower median prostate volume (32.2 mL vs . 65.0 mL, P = 0.001), and a higher median SUVmax (13.3 vs . 5.6, P <0.001). CONCLUSIONS It might be feasible to avoid biopsy before RP for patients with a high probability of PCa based on PSMA PET/CT and mpMRI. However, the diagnostic efficacy of csPCa with PI-RADS ≥4 and SUVmax of ≥4 is inadequate for performing a procedure such as RP. Further prospective multicenter studies with larger sample sizes are necessary to confirm our perspectives and establish predictive models with PSMA PET/CT and mpMRI.
Humans ; Male ; Prostatectomy/methods* ; Prostatic Neoplasms/diagnosis* ; Middle Aged ; Aged ; Positron Emission Tomography Computed Tomography/methods* ; Biopsy ; Multiparametric Magnetic Resonance Imaging ; Prostate-Specific Antigen/metabolism*

Artificial intelligence (AI), particularly deep learning, has demonstrated remarkable performance in medical imaging across a variety of modalities, including X-ray, computed tomography (CT), magnetic resonance imaging (MRI), ultrasound, positron emission tomography (PET), and pathological imaging. However, most existing state-of-the-art AI techniques are task-specific and focus on a limited range of imaging modalities. Compared to these task-specific models, emerging foundation models represent a significant milestone in AI development. These models can learn generalized representations of medical images and apply them to downstream tasks through zero-shot or few-shot fine-tuning. Foundation models have the potential to address the comprehensive and multifactorial challenges encountered in clinical practice. This article reviews the clinical applications of both task-specific and foundation models, highlighting their differences, complementarities, and clinical relevance. We also examine their future research directions and potential challenges. Unlike the replacement relationship seen between deep learning and traditional machine learning, task-specific and foundation models are complementary, despite inherent differences. While foundation models primarily focus on segmentation and classification, task-specific models are integrated into nearly all medical image analyses. However, with further advancements, foundation models could be applied to other clinical scenarios. In conclusion, all indications suggest that task-specific and foundation models, especially the latter, have the potential to drive breakthroughs in medical imaging, from image processing to clinical workflows.
Humans ; Artificial Intelligence ; Deep Learning ; Diagnostic Imaging/methods* ; Magnetic Resonance Imaging ; Tomography, X-Ray Computed ; Positron-Emission Tomography

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

Sweet syndrome (acute febrile neutrophilic dermatosis) is a relatively rare inflammatory di-sease, which is characterized by the sudden appearance of tender erythematous skin lesions, often accompanied by pyrexia and elevated neutrophil count. The pathogenesis is not clear yet. Recently, multiple studies have found the association between Sweet syndrome and infections, autoimmune diseases, malignant tumors and the application of multiple drugs. According to different causes, Sweet syndrome can be divided into three types: classical (or idiopathic) Sweet syndrome, malignancy-associated Sweet syndrome and drug-induced Sweet syndrome. Classical Sweet syndrome usually presents in women between the age of 30 to 50 years and may be related to infection, inflammatory bowel disease, or pregnancy. The clinical symptoms typically respond promptly after corticosteroid therapy. The major diagnostic criteria of classical Sweet syndrome include sudden painful erythematous skin lesions, histopathologic evidence of a dense neutrophilic infiltrate without evidence of leukocytoclastic vasculitis; minor criteria include pyrexia over 38 ℃, association with hematologic or visceral malignancies, inflammatory diseases, pregnancy or preceded by infection, prompt response to systemic glucocorticoid or potassium iodide treatment, abnormal laboratory values (three of four: erythrocyte sedimentation rate >20 mm/h, positive C-reactive protein, >8.0×10⁹/L leukocytes, >70% neutrophils). The presence of both major criteria and two of the four minor criteria are required to diagnose classical Sweet syndrome. As for the malignancy-associated Sweet syndrome, skin lesions can be found precede, follow, or at the same time with the diagnosis of hematologic malignancy or a solid tumor. At present, ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) is commonly used as a positron emission tomography computed tomography (PET/CT) imaging agent for diagnosing and screening malignant tumors. Therefore, most of the case reports on the ¹⁸F-FDG PET/CT manifestations of Sweet syndrome are malignancy-associated. Even classical Sweet syndrome is often accompanied by inflammatory bowel disease, autoimmune diseases, etc. Therefore, for patients with suspected or confirmed Sweet syndrome, it is necessary to take ¹⁸F-FDG PET/CT examination to clarify the general condition, whether it is for patients with malignant signs such as elevated tumor markers values and weight loss, or for patients with classical Sweet syndrome to exclude underlying inflammatory diseases. ¹⁸F-FDG PET/CT is often able to detect the solid tumor early, and assess the degree of hematologic malignancy and inflammatory disease. This study reported a classical Sweet syndrome case associated with inflammatory bowel disease, which was confirmed with skin and intestinal histological examination. The clinical manifestations, laboratory values, ¹⁸F-FDG PET/CT manifestations of the patient related diseases were reported, which was to improve nuclear medicine physicians' understanding of Sweet syndrome. Early diagnosis and treatment can often achieve excellent clinical effect.
Humans ; Sweet Syndrome/diagnostic imaging* ; Fluorodeoxyglucose F18 ; Positron Emission Tomography Computed Tomography ; Female

OBJECTIVES: Non-small cell lung cancer (NSCLC) is associated with poor prognosis, with 30% of patients diagnosed at an advanced stage. Mutations in the EGFR and KRAS genes are important prognostic factors for NSCLC, and targeted therapies can significantly improve survival in these patients. Although tissue biopsy remains the gold standard for detecting gene mutations, it has limitations, including invasiveness, sampling errors due to tumor heterogeneity, and poor reproducibility. This study aims to develop machine learning models based on radiomic features to predict EGFR and KRAS gene mutation status in NSCLC patients, thereby providing a reference for precision oncology. METHODS: Imaging and mutation data from eligible NSCLC patients were obtained from the publicly available Lung-PET-CT-Dx dataset in The Cancer Imaging Archive (TCIA). A three-dimensional-convolutional neural network (3D-CNN) was used to extract imaging features from the regions of interest (ROI). The LightGBM algorithm was employed to build classification models for predicting EGFR and KRAS gene mutation status. Model performance was evaluated using 5-fold cross-validation, with receiver operator characteristic (ROC) curves, area under the curve (AUC), accuracy, sensitivity, and specificity used for validation. RESULTS: The models effectively predicted EGFR and KRAS mutations in NSCLC patients, achieving an AUC of 0.95 for EGFR mutations and 0.90 for KRAS. The models also demonstrated high accuracy (EGFR 89.66%; KRAS 87.10%), sensitivity (EGFR 93.33%; KRAS 87.50%), and specificity (EGFR 85.71%; KRAS 86.67%). CONCLUSIONS A radiogenomics-machine learning predictive model can serve as a non-invasive tool for anticipating EGFR and KRAS gene mutation status in NSCLC patients.
Humans ; Carcinoma, Non-Small-Cell Lung/diagnostic imaging* ; Lung Neoplasms/diagnostic imaging* ; Mutation ; Proto-Oncogene Proteins p21(ras)/genetics* ; ErbB Receptors/genetics* ; Machine Learning ; Positron Emission Tomography Computed Tomography ; Female ; Male ; Neural Networks, Computer ; Middle Aged ; Aged

Prostate cancer is the second most common cancer in men, accounting for 14.1% of new cancer cases in 2020. The aggressiveness of prostate cancer is highly variable, depending on its grade and stage at the time of diagnosis. Despite recent advances in prostate cancer treatment, some patients still experience recurrence or even progression after undergoing radical treatment. Accurate initial staging and monitoring for recurrence determine patient management, which in turn affect patient prognosis and survival. Classical imaging has limitations in the diagnosis and treatment of prostate cancer, but the use of novel molecular probes has improved the detection rate, specificity, and accuracy of prostate cancer detection. Molecular probe-based imaging modalities allow the visualization and quantitative measurement of biological processes at the molecular and cellular levels in living systems. An increased understanding of tumor biology of prostate cancer and the discovery of new tumor biomarkers have allowed the exploration of additional molecular probe targets. The development of novel ligands and advances in nano-based delivery technologies have accelerated the research and development of molecular probes. Here, we summarize the use of molecular probes in positron emission tomography (PET), single-photon emission computed tomography (SPECT), magnetic resonance imaging (MRI), optical imaging, and ultrasound imaging, and provide a brief overview of important target molecules in prostate cancer.
Humans ; Male ; Prostatic Neoplasms/diagnosis* ; Molecular Probes ; Molecular Imaging/methods* ; Magnetic Resonance Imaging ; Positron-Emission Tomography ; Tomography, Emission-Computed, Single-Photon ; Ultrasonography ; Optical Imaging ; Biomarkers, Tumor ; Precision Medicine/methods*

OBJECTIVES: To evaluate the value of ⁶⁸Ga-DOTATATE and ¹⁸F-FDG PET/CT imaging in staging and treatment decision for gastroenteropancreatic neuroendocrine neoplasms (GEP-NEN). METHODS: This retrospective analysis was conducted in 49 patients with GEP-NEN undergoing ¹⁸F-FDG and ⁶⁸Ga-DOTATATE PET/CT imaging at our hospital from August, 2020 to March, 2023, including 34 newly diagnosed patients and 15 patients with recurrence or metastasis after treatment. GEP-NEN were classified into G1, G2, and G3 neuroendocrine tumors (NET) and neuroendocrine carcinomas (NEC) based on pathological typing. The detection efficiency were classified into 4 patterns based on the number of positive tumor lesions detected by the two tracers: ⁶⁸Ga-DOTATATE>¹⁸F-FDG (A); ⁶⁸Ga-DOTATATE=¹⁸F-FDG (B); ⁶⁸Ga-DOTATATE<¹⁸F-FDG (C); and complementation (D). The value of dual-modality imaging in staging and treatment decision were evaluated by visual analysis. RESULTS: In the 49 patients with GEP-NEN, ⁶⁸Ga-DOTATATE PET/CT was superior to ¹⁸F-FDG PET/CT for detecting systemic tumor lesions (P<0.001) and more sensitive for detecting primary/recurrent lesions, lymph node metastasis, liver metastasis, and bone metastasis (P<0.05), while ¹⁸F-FDG PET/CT had higher detection rates for lung metastasis and peritoneal metastasis (P<0.05). In terms of the detection efficiency, Pattern A was found in 46.9% (23/49) patients, Pattern B in 38.8% (19/49), Pattern C in 12.2% (6/49), and Pattern D in 2.0% (1/49). The complementary value of ¹⁸F-FDG PET/CT to ⁶⁸Ga-DOTATATE PET/CT was 0% in G1 NET patients (0/13), 8.3% in G2 NET patients (2/24), 50% in G3 NET patients (3/6), and 33.3% in NEC patients (2/6). 12.2% (6/49) of the patients had their staging confirmed or changed due to additional lesions detected by ¹⁸F-FDG PET/CT imaging, resulting subsequently in establishment or adjustment of their treatment plans. CONCLUSIONS ⁶⁸Ga-DOTATATE PET/CT imaging should be the primary choice for GEP-NEN patients. Additional ¹⁸F-FDG PET/CT imaging can potentially improve precision of staging and treatment decision-making for G2, G3 and NEC patients but provides virtually no clinical benefits for G1 NET patients.
Humans ; Positron Emission Tomography Computed Tomography/methods* ; Neuroendocrine Tumors/therapy* ; Pancreatic Neoplasms/therapy* ; Retrospective Studies ; Organometallic Compounds ; Stomach Neoplasms/therapy* ; Neoplasm Staging ; Fluorodeoxyglucose F18 ; Intestinal Neoplasms/therapy* ; Female ; Male ; Middle Aged ; Aged ; Adult

Background: Non-specific focal uptake in the skeleton is a diagnostic pitfall on 18F-PSMA-1007 PET/CT, but adjunctive measures to aid interpretation of these lesions are currently lacking. We present two cases where dual time point imaging provided additional information. Case Presentation: The first patient had a PI-RADS 3 lesion on MRI. No PSMA-avid abnormality was seen on PET, save for focal uptake in the right pubis with no anatomic correlate. Additional imaging showed a decrease in lesion SUV, and this was interpreted as benign. Another patient, diagnosed with prostate cancer, had multiple PSMA-avid pelvic foci. Two suspiciously malignant bone lesions had increasing SUV trend after dual time point imaging despite only faint sclerosis on CT. In contrast, one faint PSMA-avid lesion with no anatomic abnormality was read as benign after a decrease in SUV. A decrease in lesion SUV may point to a benign etiology, while an increase would heighten suspicion for malignancy. One possible molecular explanation is that a true PSMA-overexpressing lesion would bind to the tracer for a longer period than a false positive. Conclusion Dual time point imaging provides additional information that may be useful in the interpretation of non-specificskeletal lesions with increased 18F-PSMA-1007 uptake.
PSMA-1007 ; Positron Emission Tomography Computed Tomography

OBJECTIVE: To explore the diagnostic value of ¹⁸F-FDG PET/CT in bone marrow infiltration (BMI) of newly diagnosed diffuse large B-cell lymphoma (DLBCL), compared with the results of bone marrow biopsy (BMB) and investigate whether the BMI diagnosed by ¹⁸F-FDG PET/CT and other factors have independent prognostic values. METHODS: Ninety-four newly diagnosed DLBCL patients who underwent PET/CT in Clinical Medical College of Shanghai General Hospital of Nanjing Medical University were included. BMB was performed within 2 weeks before or after PET/CT, and standardized treatment was performed after PET/CT. The manifestations of bone marrow (BM) FDG uptake were recorded. The diagnostic criteria of BMI were BMB positive or focal BM FDG uptake confirmed by imaging follow-up. The relationship between clinical features and BM FDG uptake and the values of PET/CT and BMB in the diagnosis of BMI was analyzed. The progression-free survival (PFS) was analyzed by Kaplan-Meier survival curves, log-rank test was used to compare PFS rate, and Cox regression model was used to analyze the independent risk factors affecting PFS. RESULTS: Among 94 DLBCL patients, 34 patients showed focal BM uptake (fPET), 7 patients showed super BM uptake (sBMU), 11 patients showed diffuse homogenous uptake higher than liver (dPET), and the other 42 patients had normal BM uptake (nPET) (lower than liver). BMB positive was found in all sBMU patients, in 20.6%(7/34) of fPET patients, and in 27.3% (3/11) of dPET patients. All nPET patients had negative BMB results. dPET patients were associated with lower hemoglobin level and leukocyte count compared with nPET group (P < 0.001, P =0.026). Compared with fPET patients, sBMU patients were more likely to have B symptoms and elevated lactate dehydrogenase (LDH). A total of 44 patients were diagnosed BMI, including 17 cases with BMB⁺. The sensitivity and specificity of BMB in the diagnosis of BMI was 38.6% (17/44) and 100% (50/50), respectively. Using fPET and sBMU as criteria of PET BMI, the diagnostic sensitivity and specificity of PET/CT was 93.2% (41/44) and 100% (50/50), respectively. Kaplan-Meier analysis showed that there was no significant difference in 2-year PFS rate between nPET and dPET patients (P >0.05), while sBMU patients had lower 2-year PFS rate compared with fPET patients (P < 0.001). Multivariate analysis showed that higher Ann Arbor stage (HR=9.010, P =0.04) and sBMU (HR=3.964, P =0.002) were independent risk factors affecting PFS. CONCLUSIONS Increased BM FDG uptake of DLBCL can be manifested as dPET, fPET and sBMU. fPET and sBMU can replace BMB to diagnose BMI. Although dPET cannot completely exclude the possibility of BMI, it does not affect the prognosis, so it can be diagnosed as PET BMI negative. sBMU is an independent prognostic risk factor.
Humans ; Positron Emission Tomography Computed Tomography/methods* ; Fluorodeoxyglucose F18 ; Prognosis ; Bone Marrow/pathology* ; Retrospective Studies ; China ; Positron-Emission Tomography/methods* ; Lymphoma, Large B-Cell, Diffuse/pathology* ; Biopsy