FAP-targeted PET/NIR in Lung Malignant Tumors

Peking University People's Hospital200 enrolled

Overview

Single center, prospective, diagnostic study. Patients with stage II-IIIB resectable NSCLC diagnosed by pathology were included. After receiving standard neoadjuvant therapy (chemotherapy/immunotherapy/combination therapy), FAPI-PET/CT and fluorescence imaging were performed one week before surgery. During the surgery, a near-infrared fluorescence navigation system was used to locate the tumor lesion. After surgery, the tumor bed range was determined by pathological gold standards (HE staining+immunohistochemistry), and the predictive efficacy and localization accuracy of FAPI-PET/fluorescence were compared and analyzed.

This is a prospective, exploratory clinical study designed to evaluate the role of FAP-targeted imaging in efficacy prediction and tumor bed delineation in patients with NSCLC undergoing surgical resection after neoadjuvant therapy. Following neoadjuvant treatment, enrolled patients will undergo preoperative FAP-targeted PET imaging to assess treatment response and identify metabolically active tumor-associated stromal regions. Surgical resection will be performed according to standard clinical practice. Immediately after tumor resection, ex vivo fluorescence imaging of the surgical specimen will be conducted using a EB-FAPI fluorescence probe. Based on fluorescence signal distribution, systematic multipoint sampling will be performed across tumor center, tumor margin, and adjacent normal tissues. Routine pathological sampling will be conducted in parallel according to standard protocols. Additional fluorescence-guided sampling will be performed in regions with persistent fluorescence signals. Histopathological analysis will be used as the reference standard to evaluate tumor bed distribution, residual tumor presence, and pathological response. The concordance between fluorescence imaging, PET imaging, and pathological findings will be analyzed. The study will also evaluate whether fluorescence-guided sampling can improve detection of residual tumor and reduce false-negative pathological assessments. This study aims to establish a multimodal imaging approach integrating preoperative molecular imaging and intraoperative fluorescence guidance to enhance tumor bed visualization and improve the accuracy of pathological response assessment after neoadjuvant therapy in NSCLC.

Study Type

OBSERVATIONAL

Enrollment

200

Interventions

PET/CT scansDIAGNOSTIC_TEST

PET Dynamic Data: The tracer is administered based on the patient's body weight at approximately 0.06-0.12 mCi/kg. PET scanning is initiated simultaneously with tracer injection, followed by a flush with 10 ml of normal saline. The image acquisition matrix is 192 × 192. Reconstruction is performed using the OSEM algorithm with 4 iterations and 20 subsets, incorporating time-of-flight attenuation correction, scatter correction, and random correction. The total duration of PET dynamic data acquisition is 60 minutes. Processing of PET dynamic scan data: Dynamic PET images are divided into 2-minute intervals to obtain time-activity curves by extracting the radioactivity within regions of interest at different time points, reflecting tracer uptake and enabling calculation of the time to peak. Multi-modality imaging data are analyzed by radiologists with over 10 years of experience in diagnosing respiratory diseases.

Eligibility

Sex: ALLMin age: 18 YearsMax age: 70 Years

Medical Language ↔ Plain English

Inclusion Criteria: * Age between 18 and 70 years old; * Have complete clinical and imaging data; * Prior to neoadjuvant therapy, the biopsy pathology showed lung cancer; * Able to retain sufficient tumor tissue for testing and research; * Sign informed consent. Exclusion Criteria: * Previously combined with other malignant tumors or received other anti-tumor treatments; * Failure to collect sufficient tumor tissue for testing and research; * The duration of neoadjuvant therapy is less than 3 cycles; * The dynamic scanning image quality of multimodal probe PET cannot meet the analysis standards or is missing; * Lack of clinical and imaging data; * There are situations where other researchers consider it inappropriate to participate in this study

Outcomes

Primary Outcomes

Accuracy of EB-FAPI fluorescence imaging for tumor bed delineation after neoadjuvant therapy

To evaluate the accuracy of intraoperative FAP-targeted fluorescence imaging in identifying the tumor bed after neoadjuvant therapy in NSCLC patients, using histopathological assessment as the reference standard. Tumor bed regions identified by fluorescence will be compared with pathological mapping of tumor, regression bed, and residual tumor distribution.

Time frame: From surgery to completion of postoperative pathological evaluation (within 2 weeks after surgery)

Diagnostic performance of preoperative FAPI PET for treatment response assessment

To evaluate the ability of preoperative FAPI PET imaging to predict pathological response after neoadjuvant therapy, using pathological response (pCR/MPR/non-MPR) as the reference standard.

Time frame: From preoperative imaging to postoperative pathological assessment (within 4 weeks)

Secondary Outcomes

Correlation between fluorescence signal intensity and pathological features

To evaluate the correlation between fluorescence signal intensity and pathological parameters, including tumor cell density, regression bed, and FAP expression (e.g., immunohistochemistry), across tumor (T), margin (M), and normal (N) regions.

Time frame: Postoperative specimen analysis (within 2-3 weeks after surgery)

Tumor-to-background ratio (TBR) of fluorescence imaging in surgical specimens

To quantify fluorescence signal contrast between tumor, tumor margin, and normal tissues, and determine optimal thresholds for tumor bed delineation.