This prospective, single-center, open-label exploratory diagnostic study aims to evaluate the safety, feasibility, and diagnostic performance of the novel Sortilin-targeted PET tracer 68Ga-SorB in patients with solid tumors. Eligible participants with confirmed or suspected melanoma, hepatocellular carcinoma, lung cancer, pancreatic cancer, breast cancer, or ovarian cancer will undergo 68Ga-SorB PET/CT imaging. The imaging findings will be compared with standard-of-care 18F-FDG PET/CT, using pathology results and/or clinical follow-up as the reference standard.
The primary objectives are to evaluate the safety and tolerability of 68Ga-SorB, assess imaging feasibility, and characterize tumor uptake using quantitative PET parameters, including SUVmax and tumor-to-background ratio (TBR). Secondary exploratory objectives include comparing lesion detection between 68Ga-SorB PET/CT and 18F-FDG PET/CT, assessing diagnostic sensitivity and specificity, evaluating imaging characteristics across different tumor types, and exploring the correlation between Sortilin expression and tracer uptake. This study will provide preliminary clinical evidence supporting the development of Sortilin-targeted molecular imaging and future theranostic applications.
- Adults aged 18 to 75 years.
Histologically confirmed or clinically suspected melanoma, hepatocellular carcinoma, lung cancer, breast cancer, pancreatic cancer, or ovarian cancer.
Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1.
White blood cell count ≥ 4.0 × 10^9/L or absolute neutrophil count ≥ 1.5 × 10^9/L;
Pregnant or breastfeeding women.
Severe dysfunction of major organs (including heart, liver, or kidney) that, in the investigator's judgment, would make participation inappropriate.
Inability to tolerate PET/CT imaging or complete study follow-up.
Any other condition that, in the investigator's judgment, makes the participant unsuitable for the study.
Single group
68Ga-SorB PET/CT
Diagnostic testParticipants will receive a single intravenous administration of 68Ga-SorB (approximately 3.7 MBq/kg), followed by whole-body PET/CT imaging approximately 60 minutes after injection. The imaging findings will be compared with clinically indicated 18F-FDG PET/CT and reference standard findings to evaluate the safety, feasibility, biodistribution, tumor uptake, and exploratory diagnostic performance of 68Ga-SorB PET/CT.
Incidence of adverse events related to 68Ga-SorB PET/CT
Incidence and severity of adverse events (AEs) and serious adverse events (SAEs) related to administration of 68Ga-SorB, graded according to CTCAE.
Successful completion of 68Ga-SorB PET/CT imaging
Proportion of participants completing 68Ga-SorB PET/CT with evaluable image quality.
Tumor uptake of 68Ga-SorB measured by SUVmax
Maximum standardized uptake value (SUVmax) of target lesions measured on 68Ga-SorB PET/CT.
Lesion detection rate on 68Ga-SorB PET/CT
Detection rate of reference standard-confirmed primary and metastatic tumor lesions visually identified on 68Ga-SorB PET/CT. Lesion detection will be assessed by lesion-based visual interpretation of 68Ga-SorB PET/CT images by nuclear medicine physicians. The detection rate will be calculated as the percentage of reference standard-confirmed lesions detected on 68Ga-SorB PET/CT. The reference standard will include pathology, clinical diagnosis, and/or imaging follow-up, as applicable.
Cohen's kappa coefficient for lesion detection agreement between 68Ga-SorB PET/CT and 18F-FDG PET/CT
Agreement in lesion detection between 68Ga-SorB PET/CT and clinically indicated 18F-FDG PET/CT. For each evaluable lesion, detection status will be recorded as detected or not detected on each PET/CT modality based on lesion-based visual image interpretation by nuclear medicine physicians. Agreement between the two PET/CT modalities will be assessed using Cohen's kappa coefficient with 95% confidence interval. Unit of Measure: Cohen's kappa coefficient, unitless.
Diagnostic sensitivity of 68Ga-SorB PET/CT for lesion detection
Diagnostic sensitivity of 68Ga-SorB PET/CT for lesion detection will be calculated using pathology, clinical diagnosis, and/or imaging follow-up as the reference standard. Lesion detection will be assessed by lesion-based visual interpretation of 68Ga-SorB PET/CT images by nuclear medicine physicians. Unit of Measure: Percentage.
Tumor SUVmax on 68Ga-SorB PET/CT by tumor type
Maximum standardized uptake value of tumor lesions on 68Ga-SorB PET/CT across different tumor types, including malignant melanoma, hepatocellular carcinoma, lung cancer, breast cancer, pancreatic cancer, and ovarian cancer, as applicable. SUVmax will be measured on fused PET/CT images using ROI/VOI delineation. Unit of Measure: Unitless standardized uptake value.
Click on the lead sponsor to view all of their trials.
