The pathogenesis of ovarian cancer is concealed, which is prone to recurrence and metastasis and carries a very poor prognosis. The precise imaging assessment of abdominopelvic tumor burden is crucial for debulking surgery decision in patients with ovarian cancer. Fibroblast activation protein inhibitor (FAPI) PET imaging has shown a great prospect of clinical application, which provides a new imaging technique for the diagnosis and staging of ovarian cancer. This review summarizes the clinical value and research progress of 68Ga-FAPI PET in the diagnosis and treatment of ovarian cancer.

In recent years, targeted PET imaging of chemokine CXC subfamily receptor 4 (CXCR4) has become a prominent area of research, offering considerable potential for precise diagnosis, tracking disease progression noninvasively, guiding therapeutic strategies, and monitoring treatment responses. This article reviews recent achievements in noninvasive molecular imaging techniques targeting CXCR4 expression, with a particular focus on the pathophysiological mechanisms underlying CXCR4 and the clinical utility of the molecular probe 68Ga-pentixafor PET for diagnosis and treatment. Furthermore, the paper discusses the clinical translation of CXCR4 molecular imaging and highlights prospective research directions.

Objective:To investigate the value of tumor and adipose tissue metabolic parameters from baseline 18F-FDG PET/CT in predicting the efficacy and prognosis of immunotherapy in patients with advanced nasopharyngeal carcinoma (NPC). Methods:From February 2019 to February 2022, 112 patients (91 males, 21 females, age 21-73 years) with advanced NPC who were treated with programmed death-1 (PD-1) inhibitors at Sun Yat-Sen University Cancer Center were retrospectively included. All patients underwent baseline PET/CT examination. Tumor and adipose tissue metabolic parameters were measured and calculated. Patients were divided into clinical benefit and non-clinical benefit groups, and Mann-Whitney U test or χ2 test was used to assess the differences between groups. Prognostic analysis of progression-free survival (PFS) was performed using multivariate Cox proportional hazards regression model and a prognostic stratification system was constructed. Results:Of the 112 patients, 85 were in the clinical benefit group and 27 were in the non-clinical benefit group. In non-clinical benefit group and clinical benefit group, the metabolic tumor volume (MTV) of primary tumor (PT-MTV) were 47.7(7.7, 81.2) and 14.0(5.7, 27.1)cm 3, total lesion glycolysis (TLG) of primary tumor (PT-TLG) were 228.9(27.4, 492.8) and 72.7(20.4, 165.5)g, whole-body MTV (WB-MTV) were 94.2(45.9, 215.4) and 61.3(31.6, 104.3)cm 3, whole-body TLG (WB-TLG) were 605.5(214.1, 1 402.5) and 319.2(172.4, 632.8)g, SUV max of visceral adipose tissue (SUV max-VAT) were 0.77(0.55, 0.91) and 0.62(0.48, 0.76), respectively ( Z values: from -2.72 to -1.96, all P<0.05). The proportion of patients with lung metastasis in non-clinical benefit group was higher than that in clinical benefit group (44.4%(12/27) vs 23.5%(20/85); χ2=4.39, P=0.036). PT-MTV (hazard ratio ( HR)=2.807, 95% CI: 1.540-5.118, P=0.001) and the presence of lung metastases ( HR=1.691, 95% CI: 1.012-2.823, P=0.045) were independent predictive factors for PFS in multivariate analysis. The prognostic prediction model based on the two predictive factors was able to significantly differentiate the prognosis in patients. Conclusions:Baseline tumor metabolic parameters and SUV max-VAT are associated with the efficacy of immunotherapy in patients with advanced NPC. PT-MTV and lung metastasis can independently predict PFS. The constructed prediction model can stratify patients′ prognosis.

Objective:To evaluate the application potential of the bimodal ultrasound/near-infrared (NIR) composite nanoscale probe Arg-Gly-Asp (RGD)/Ag 2Te/perfluoropentane (PFP) @ mesoporous silica nanoparticles (MSN) in the diagnosis and treatment of microvascular diseases. Methods:Nanoprobes loaded with RGD, PFP and Ag 2Te were prepared by ultrasound sonication and carbodiimide method. The characterization of the nanoprobes was determined. The imaging performance, photothermal response, and target-seeking ability of the nanoprobes under NIR irradiation were verified. The biosafety of the nanoprobes was examined, and the thrombolytic ability of the nanoprobes was evaluated. The mice were observed to visualize microvessels of the abdominal wall under the NIR-Ⅱ imaging, and the microvascular visualization ability of the nanoprobes was evaluated. Results:The particle size of nanoprobes was (205.3±2.9) nm and the potential was (2.05±0.58) mV. The coupling rate of the RGD was (82.27±0.36)%, the encapsulation rate of the quantum dots was (80.80±3.26)%, and the photostability of the quantum dots was good. The fluorescence intensity was enhanced with the increase of the mass concentration of RGD/Ag 2Te/PFP@MSN, and the warming effect was more obvious. After ultrasound and NIR irradiation, the thrombolysis rate was significantly increased. RGD/Ag 2Te/PFP@MSN successfully realized NIR-Ⅱ fluorescence imaging of mice microvessels. The cytotoxicity assay and hemolysis assay showed that the probe had a good biosafety. Conclusion:The RGD/Ag 2Te/PFP@MSN nanoprobe is a potential strategy for targeted therapy of thrombotic diseases, combining dual-modality therapy of ultrasound and NIR to offer new possibilities for non-invasive and visual diagnosis and treatment of microvascular embolism.

SPECT myocardial perfusion imaging (MPI) can obtain many parameters such as myocardial perfusion, morphology, function and mechanical synchronization in one stop, which has become an essential non-invasive examination technique in the diagnosis and treatment of various cardiovascular diseases (CVD). With the continuous development of cardiac SPECT instrument, imaging scheme and image reconstruction algorithm, its application in the diagnosis and treatment of CVD is expanding. This paper reviews the research progress of qualitative, semi-quantitative and quantitative parameters of SPECT MPI in recent years, and expounds the threshold, influencing factors and application value of various parameters.

Due to the specificity of radiopharmaceuticals for targeted α radionuclide therapy, such as radioactivity and radiation damage risk, it is necessary to estimate the internal radiation dose in preclinical evaluation to correctly evaluate the efficacy and safety of the drug, as well as in subsequent clinical studies. This review illustrates current research status of estimating internal radiation dose of targeted α radionuclide therapeutic radiopharmaceuticals based on preclinical studies, in order to add insights for understanding estimation of radiopharmaceuticals internal radiation dose and provide reference for the preclinical evaluation of radiopharmaceuticals.

Radiomics technology extracts high-dimensional quantitative radiomics features from medical imaging to achieve intelligent analysis of nuclear medicine and other medical imaging, which has important application value on improving the diagnostic performance of imaging. However, it has been demonstrated that variability in image acquisition, reconstruction settings, and technological differences can affect the reproducibility of radiomics features, which may lead to variability in the calculations of radiomics models across different centers or scanners, affecting the stability of the performance of radiomics models (i.e., generalizability) in the clinical translation of radiomics models. For this reason, researchers at home and abroad have conducted extensive studies on the influencing factors of radiomics features and harmonization strategies for heterogeneous imaging data in recent years to improve the reproducibility of radiomics features and the generalizability of radiomics models. This paper reviews the above research progress mainly from the aspect of PET imaging in nuclear medicine.

Integrin is a kind of transmembrane glycoprotein, which is highly expressed in tumor neovascular endothelial cells and various tumor cells, but lowly or negatively expressed in normal tissues. Integrin-targeted diagnostic or therapeutic radiopharmaceuticals can non-invasively display tumor characteristics in vivo, evaluate angiogenesis and perform targeted radiotherapy for tumors, which have great clinical application value. This article reviews the research progress of radiopharmaceuticals targeting integrins in tumor diagnosis and treatment.

Diffuse large B-cell lymphoma(DLBCL), as the most common subtype of non-Hodgkin′s lymphoma, requires precise assessment of treatment efficacy and prognosis for optimal patient care planning. 18F-FDG PET/CT, an advanced imaging technique, has become a standard tool for evaluating treatment outcomes and predicting prognoses in patients with DLBCL. Currently, the Deauville scoring system, based on a 5-point visual analog scale, is the predominant method for assessing treatment efficacy and prognosis. However, the ambiguity of some scoring criteria and the subjectivity in interpretation somewhat limit its clinical application value. In recent years, a novel semi-quantitative method, the ratio of the SUV max of the lesion to the SUV of the liver (RLL), has gained attention and shown promise in the evaluation of treatment efficacy and prognostic analysis for DLBCL. This article aims to review the application of the RLL evaluation system in the assessment of DLBCL efficacy and prognosis, the latest research advancements, and the future development trends.

Skin malignant tumors mostly occur in the light exposure site. Early diagnosis and treatment can effectively improve the survival rate of patients. Histopathological examination is the gold standard for clinical diagnosis of skin malignant tumors, but this method is an invasive operation which brings pain to patients and takes a long time, and may cause problems such as incision infection and scar formation. In recent years, spectroscopy technology has developed rapidly. It is a non-invasive real-time detection method, which can be simply operated, and has a high sensitivity. It has been gradually applied to the diagnosis of skin malignant tumors. This paper reviews the application progress of spectroscopy technology, including fluorescence spectroscopy, Raman spectroscopy and infrared spectroscopy in the diagnosis of skin malignant tumors.