A Prospective, Single-Center, Open-Label Exploratory Study of 68Ga-SorB PET/CT Imaging for the Diagnosis of Sortilin-Positive Solid Tumors
Trial Snapshot
- Phase
- Not Applicable
- Status
- Recruiting
- Enrollment
- 50
- Locations
- 1
- Primary Endpoint
- Incidence of adverse events related to 68Ga-SorB PET/CT
Study Overview
Brief Summary
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.
Detailed Description
Background Sortilin is a type I transmembrane receptor belonging to the VPS10 receptor family. It is highly expressed in a variety of malignancies, including melanoma, hepatocellular carcinoma, lung cancer, pancreatic cancer, breast cancer, and ovarian cancer, while showing relatively low expression in most normal tissues. Due to its tumor-specific expression pattern and efficient receptor-mediated internalization, Sortilin has emerged as a promising molecular target for cancer imaging and targeted theranostic applications.
Although ^18F-FDG PET/CT is widely used for oncologic imaging, its diagnostic performance may be limited by nonspecific uptake in inflammatory lesions, resulting in false-positive findings. Therefore, a more tumor-specific PET tracer may improve lesion detection and diagnostic accuracy.
Study Design This is a prospective, single-center, open-label, exploratory diagnostic imaging study designed to evaluate the clinical performance of the novel Sortilin-targeted PET radiotracer ^68Ga-SorB. Approximately 40-50 adult patients with confirmed or suspected melanoma, hepatocellular carcinoma, lung cancer, pancreatic cancer, breast cancer, pancreatic cancer, or ovarian cancer will be enrolled. All participants will undergo ^68Ga-SorB PET/CT imaging according to the study protocol. Standard-of-care ^18F-FDG PET/CT performed within the predefined time window will be used as the comparator whenever available.
Histopathological findings and/or clinical and imaging follow-up will serve as the reference standard for evaluating diagnostic performance.
Study Objectives The primary objectives are to evaluate the safety and tolerability of ^68Ga-SorB, assess imaging feasibility, and characterize tracer biodistribution and tumor uptake using quantitative PET parameters, including SUVmax and tumor-to-background ratio (TBR).
Study Design
- Study Type
- Interventional
- Allocation
- Na
- Intervention Model
- Single Group
- Primary Purpose
- Diagnostic
- Masking
- None
Masking Description
PET/CT images will be independently interpreted by two experienced nuclear medicine physicians who are blinded to pathology results, clinical follow-up findings, and final clinical diagnosis. Any discrepancies will be resolved by a third independent nuclear medicine physician.
Eligibility Criteria
- Ages
- 18 Years to 75 Years (Adult, Older Adult)
- Sex
- All
- Accepts Healthy Volunteers
- No
Inclusion Criteria
- •- 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
- •Adequate hematologic, hepatic, renal, and coagulation function:
- •White blood cell count ≥ 4.0 × 10^9/L or absolute neutrophil count ≥ 1.5 × 10^9/L;
- •Platelet count ≥ 100 × 10^9/L;
- •Hemoglobin ≥ 90 g/L;
- •PT or APTT ≤ 1.5 × upper limit of normal (ULN);
- •Total bilirubin ≤ 1.5 × ULN;
- •ALT and AST ≤ 2.5 × ULN (or ≤ 5 × ULN for participants with liver metastases);
- •ALP ≤ 2.5 × ULN (or ≤ 4.5 × ULN for participants with bone or liver metastases);
- •Blood urea nitrogen and serum creatinine ≤ 1.5 × ULN.
- •Normal cardiac function.
- •Estimated life expectancy of at least 12 weeks.
- •Willing and able to comply with study procedures and follow-up.
- •At least one measurable target lesion according to RECIST version 1.
- •Participants of childbearing potential agree to use effective contraception during the study and for 3 months after PET/CT imaging.
- •Clinically indicated to undergo 18F-FDG PET/CT for tumor evaluation.
- •Able to understand the study procedures and provide written informed consent.
Exclusion Criteria
- •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.
Arms & Interventions
68Ga-SorB PET/CT Imaging
Participants with suspected or confirmed malignant tumors will receive a single intravenous administration of 68Ga-SorB followed by PET/CT imaging. Imaging findings will be compared with clinically indicated 18F-FDG PET/CT performed within the predefined time window. No therapeutic intervention will be administered as part of this study.
Intervention: 68Ga-SorB PET/CT (Diagnostic Test)
Outcomes
Primary Outcomes
Incidence of adverse events related to 68Ga-SorB PET/CT
Time Frame: From tracer administration until completion of the imaging visit (approximately 24 hours).
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
Time Frame: At completion of PET/CT imaging (approximately 60 minutes after tracer injection)
Proportion of participants completing 68Ga-SorB PET/CT with evaluable image quality.
Tumor uptake of 68Ga-SorB measured by SUVmax
Time Frame: At PET/CT imaging (approximately 60 minutes after tracer injection)
Maximum standardized uptake value (SUVmax) of target lesions measured on 68Ga-SorB PET/CT.
Secondary Outcomes
- Lesion detection rate on 68Ga-SorB PET/CT(At completion of 68Ga-SorB PET/CT imaging, with reference-standard adjudication up to approximately 3 months after imaging.)
- Cohen's kappa coefficient for lesion detection agreement between 68Ga-SorB PET/CT and 18F-FDG PET/CT(Within 2 weeks after completion of both PET/CT examinations.)
- Diagnostic sensitivity of 68Ga-SorB PET/CT for lesion detection(Within approximately 3 months after PET/CT imaging, following completion of pathology assessment, clinical diagnosis, and/or imaging follow-up.)
- Tumor SUVmax on 68Ga-SorB PET/CT by tumor type(At completion of 68Ga-SorB PET/CT imaging, approximately 60 minutes after tracer administration.)
- Correlation between Sortilin expression H-score and 68Ga-SorB PET/CT uptake parameters(Within approximately 3 months after PET/CT imaging, following completion of pathological assessment.)
- Percentage of participants with a change in clinical diagnosis or tumor staging after 68Ga-SorB PET/CT(Within approximately 3 months after 68Ga-SorB PET/CT imaging.)
- Diagnostic specificity of 68Ga-SorB PET/CT for lesion detection(Within approximately 3 months after PET/CT imaging, following completion of pathology assessment, clinical diagnosis, and/or imaging follow-up.)
- Diagnostic accuracy of 68Ga-SorB PET/CT for lesion detection(Within approximately 3 months after PET/CT imaging, following completion of pathology assessment, clinical diagnosis, and/or imaging follow-up.)
- Positive predictive value of 68Ga-SorB PET/CT for lesion detection(Within approximately 3 months after PET/CT imaging, following completion of pathology assessment, clinical diagnosis, and/or imaging follow-up.)
- Negative predictive value of 68Ga-SorB PET/CT for lesion detection(Within approximately 3 months after PET/CT imaging, following completion of pathology assessment, clinical diagnosis, and/or imaging follow-up.)