The first-in-human preclinical evaluation of the new probe [123I] I-PSMA-7 for real-time intraoperative targeted biopsy and SPECT/CT imaging in prostate cancer

Q: Why was [123I] I-PSMA-7 developed for prostate biopsy?

PSMA/PET and MRI can indicate lesion location, but biopsy tissue cannot be confirmed in real time as targeted PCa. The study aims to use radionuclide counts to confirm targeting immediately during biopsy.

Q: How was [123I] I-PSMA-7 evaluated in patients?

The probe was synthesized and tested in a clinical cohort of patients with suspected PCa. Injection and biopsy were about 24 hours apart, and tracer activity in biopsy lesions was measured as counts per minute (cpm) using a gamma-counter.

Q: What diagnostic performance and imaging benefits were reported?

Animal experiments supported safety, targeting, and effectiveness, with the tumor-to-muscle ratio greatest at 24 hours. In clinical biopsy cores, higher cpm values and strong discrimination metrics (reported AUC values and cutoffs) were achieved, and SPECT/CT imaging improved at higher activities.

Sep 21, 2026

Uploaded by Sage

PSMA/PET has increasing use in detecting prostate cancer (PCa), yet biopsy cannot immediately confirm whether sampled tissue matches the targeted lesion area. This study develops and tests the novel radioprobe [123I] I-PSMA-7 to enable instant confirmation for prostate biopsy and improve PCa detection. A high-affinity probe was synthesized and evaluated across preclinical experiments and a prospective clinical setting with suspected PCa patients, using biopsy lesion counts and imaging readouts.

LanguageEnglish

CategoryResearch & Report

FormatPDF

Pages10

Reading Time25 min

AccessFree to download

Introduction

Background and clinical need for real-time targeted confirmation

Materials and methods

Probe development and evaluation setup

Results

Safety, targeting, and diagnostic performance

Conclusion

Clinical implications for biopsy reduction and imaging performance

European Journal of Nuclear Medicine and Molecular Imaging (2024) 51:4141–4150 [https://doi.org/10.1007/s00259-024-06833-4](https://doi.org/10.1007/s00259-024-06833-4) ORIGINAL ARTICLE The first-in-human preclinical evaluation of the new probe [123I] I-PSMA-7 for real-time intraoperative targeted biopsy and SPECT/CT imaging in prostate cancer Xiaohui Luan1,2 · Shaoxi Niu3 · Yachao Liu1 · Xiaojun Zhang1 · Xiaodan Xu1 · Shuwei Sun1 · Yabing Sun1 · Jingfeng Zhang1,2 · Yuan Wang1 · Zhiqiang Chen2,3 · Yimin Chen4 · Mengchao Cui4 · Ruimin Wang1,2 · Xu Zhang2,3 · Jinming Zhang1,2 · Baixuan Xu1,2 Received: 25 March 2024 / Accepted: 4 July 2024 / Published online: 23 July 2024 © The Author(s) 2024 Abstract Purpose PSMA/PET has been increasingly used to detect PCa, and PSMA/PET-guided biopsy has shown promising results. However, it cannot be confirmed immediately whether the tissues are the targeted area. In this study, we aimed to develop a novel probe,[ 123I]I-PSMA-7 . First, we hope that [ 123I]I-PSMA-7 can provide instant confirmation for prostate biopsy. Second, we hope it will help detect PCa. Methods We synthesized a high-affinity probe,[ 123I]I-PSMA-7, and evaluated its properties. We included ten patients with suspected PCa and divided them into two groups. The injection and biopsy were approximately 24 h apart. The activity in biopsy lesions was measured as the cpm by a γ-counter. Moreover, we enrolled 3 patients to evaluate the potential of [ 123I] I-PSMA-7 for detecting PCa. Results Animal experiments verified the safety, targeting and effectiveness of [ 123I]I-PSMA-7, and the tumor-to-muscle ratio was greatest at 24 h, which confirmed the results of this study in humans. After injection of 185MBq [ 123I]I-PSMA-7, 18/55 cores were positive, and the cpm was significantly greater (4345 ±3547 vs. 714 ±547, P <0.001), with an AUC of 0.97 and a cutoff of 1312 (sens/spec of 94.40%/91.90%). At a lower dose, 10/55 biopsy cores were cancerous, and the cpm was 2446 ± 1622 vs. 153 ±112 (P<0.001) . TheAUC was 1, with a cutoff value of 490 (sens/spec of 100%) . When the radiopharmaceuticals were added to 370 MBq, we achieved better SPECT/CT imaging. Conclusion With the aid of [ 123I]I-PSMA-7 and via cpm-based biopsy, we can reduce the number of biopsies to a minimum operation. [ 123I]I-PSMA-7 PSMA SPECT/CT can also provide good imaging results. Trial registration Chinese Clinical trial registry ChiCTR2300069745, Registered 24 March 2023 Keywords [ 123I]I-PSMA-7 · Real-time targeted biopsy · PSMA SPECT/CT imaging · Clinical study 􀀍 Xu Zhang [xzhang301@163.com](xzhang301@163.com) 􀀍 Jinming Zhang [zhangjm301@163.com](zhangjm301@163.com) 􀀍 Baixuan Xu [xbx301@163.com](xbx301@163.com) 1 Department of Nuclear Medicine, The First Medical Centre of Chinese PLA General Hospital, Beijing, China 2 Chinese PLA General Hospital, Chinese PLA Medical School, Beijing, China 3 Department of Urology, The Third Medical Centre of Chinese PLA General Hospital, Beijing, China 4 Key Laboratory of Radiopharmaceuticals, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing, China Introduction Prostate cancer (PCa) is one of the leading causes of cancer death in men worldwide [1]. Accurate diagnosis of PCais crucial for patients to choose treatments, such as surgery, radiation therapy and immunotherapy [2] . Prostatespecific membrane antigen (PSMA) positron emission tomography (PET) has resulted in the increasing detection of PCa [3] . However, prostate biopsy (PB) remains a mandatory step for confirming PCa, although almost 25% of patients will experience complication such as lower urinary tract symptoms [4] . The sensitivity of transrectal ultrasound (TRUS) of PB is only approximately 50% [5] . Multiparametric MRI (mpMRI) is recommended for prostate cancer diagnosis, and MRI-guided transrectal ultrasound (MR-TRUS) biopsy increases the detection of clinically significant PCa (csPCa) [6] . MR-TR

FAQs

Why was [123I] I-PSMA-7 developed for prostate biopsy?

PSMA/PET and MRI can indicate lesion location, but biopsy tissue cannot be confirmed in real time as targeted PCa. The study aims to use radionuclide counts to confirm targeting immediately during biopsy.

How was [123I] I-PSMA-7 evaluated in patients?

The probe was synthesized and tested in a clinical cohort of patients with suspected PCa. Injection and biopsy were about 24 hours apart, and tracer activity in biopsy lesions was measured as counts per minute (cpm) using a gamma-counter.

What diagnostic performance and imaging benefits were reported?

Animal experiments supported safety, targeting, and effectiveness, with the tumor-to-muscle ratio greatest at 24 hours. In clinical biopsy cores, higher cpm values and strong discrimination metrics (reported AUC values and cutoffs) were achieved, and SPECT/CT imaging improved at higher activities.

Sep 21, 2026

Uploaded by Sage