Background <p>Sarcomas represent a heterogeneous group of mesenchymal tumors that, despite accounting for only 1% of cancers worldwide, rank among the top five causes of cancer-related deaths in patients under 20 years old. Surgical resection remains the primary treatment for these malignancies, as effective systemic therapies are limited, particularly for high-grade disease. However, surgical outcomes are often compromised by incomplete resection, leading to high local and distal recurrence rates. Intraoperative molecular imaging has emerged as a promising approach to improve surgical outcomes but has been hindered by the lack of tumor-specific targeting agents. Fibroblast activation protein (FAP), selectively expressed by mesenchymal tumors and absent in healthy tissues, presents a promising target for fluorescence-guided cancer resections.</p> Results <p>We demonstrate that 41% of human sarcomas express FAP, with expression correlating with higher histologic grade. The FAP-S0456 optical tracer specifically bound to FAP-expressing sarcomas with minimal binding to normal tissues, exhibiting excellent tumor-to-background ratios (3.8 ± 0.43). In vitro studies confirmed FAP-S0456’s specificity for human FAP with a dissociation constant of approximately 10 nM. In murine xenograft models, the tracer accurately identified both primary tumors and pulmonary metastases of FAP-expressing sarcomas. Importantly, using needle confocal laser endomicroscopy, we demonstrated that FAP-S0456 enables real-time, single-cell visualization of metastatic tumor cells during surgery, including micrometastases not detected by conventional imaging.</p> Conclusions <p>FAP-S0456 represents a promising molecular imaging agent for the detection and surgical removal of primary and metastatic sarcomas. Its high specificity for FAP-expressing tumor cells, favorable biodistribution profile, and ability to detect microscopic disease offer potential to improve complete surgical resection. These findings support the development of FAP-targeted fluorescence-guided surgery for sarcoma patients, which may lead to improved oncologic outcomes, particularly for those with pulmonary metastases where complete surgical clearance is critical for survival.</p>

错误:搜索内容不能为空,请输入英文关键词
错误:关键词超出字数限制,请精简
高级检索

A fibroblast activation protein targeted optical tracer for identifying primary and metastatic sarcoma during resection

  • Feredun Azari,
  • Gregory T. Kennedy,
  • Ian Folkert,
  • Gregory Jones,
  • Ashley Chang,
  • Andrew Conner,
  • Elizabeth Bernstein,
  • Bilal Nadeem,
  • Neil T. Sullivan,
  • Evgeniy Eruslanov,
  • Steven Albelda,
  • Philip Low,
  • Sunil Singhal

摘要

Background

Sarcomas represent a heterogeneous group of mesenchymal tumors that, despite accounting for only 1% of cancers worldwide, rank among the top five causes of cancer-related deaths in patients under 20 years old. Surgical resection remains the primary treatment for these malignancies, as effective systemic therapies are limited, particularly for high-grade disease. However, surgical outcomes are often compromised by incomplete resection, leading to high local and distal recurrence rates. Intraoperative molecular imaging has emerged as a promising approach to improve surgical outcomes but has been hindered by the lack of tumor-specific targeting agents. Fibroblast activation protein (FAP), selectively expressed by mesenchymal tumors and absent in healthy tissues, presents a promising target for fluorescence-guided cancer resections.

Results

We demonstrate that 41% of human sarcomas express FAP, with expression correlating with higher histologic grade. The FAP-S0456 optical tracer specifically bound to FAP-expressing sarcomas with minimal binding to normal tissues, exhibiting excellent tumor-to-background ratios (3.8 ± 0.43). In vitro studies confirmed FAP-S0456’s specificity for human FAP with a dissociation constant of approximately 10 nM. In murine xenograft models, the tracer accurately identified both primary tumors and pulmonary metastases of FAP-expressing sarcomas. Importantly, using needle confocal laser endomicroscopy, we demonstrated that FAP-S0456 enables real-time, single-cell visualization of metastatic tumor cells during surgery, including micrometastases not detected by conventional imaging.

Conclusions

FAP-S0456 represents a promising molecular imaging agent for the detection and surgical removal of primary and metastatic sarcomas. Its high specificity for FAP-expressing tumor cells, favorable biodistribution profile, and ability to detect microscopic disease offer potential to improve complete surgical resection. These findings support the development of FAP-targeted fluorescence-guided surgery for sarcoma patients, which may lead to improved oncologic outcomes, particularly for those with pulmonary metastases where complete surgical clearance is critical for survival.