A groundbreaking study published in Surgery Open Science reveals that contrast-enhanced computed tomography (CE-CT) can effectively predict surgical benefits of neoadjuvant tyrosine kinase inhibitor (TKI) therapy in patients with non-metastatic gastrointestinal stromal tumor (GIST).
Significant Surgical Benefits Observed
The research, conducted at Leiden University Medical Center, demonstrated that neoadjuvant TKI treatment led to less invasive or complex surgeries in more than half of the study participants. Of 39 evaluated patients, 22 experienced significant surgical benefits, with a median neoadjuvant treatment interval of 8.3 months.
Dr. Ylva A. Weeda, lead study author from the Department of Radiology at Leiden University Medical Center, stated, "This study shows that using size-based radiological response criteria based on CE-CT imaging could accurately predict surgical benefit achieved by neoadjuvant treatment in non-metastatic GIST."
Early Response Prediction
The study revealed a marked difference in tumor volume reduction between patients who benefited from the treatment and those who did not. Within the first three months, 14 of 19 surgical-benefit patients demonstrated an initial volume reduction exceeding 66%, followed by a modest median reduction of 3.1% thereafter.
Surgical Outcomes and Procedure Modifications
The neoadjuvant TKI therapy enabled several significant surgical modifications:
- Six patients' procedures were downgraded from partial gastrectomy to local excision
- One patient avoided total gastrectomy in favor of partial gastrectomy
- Five patients benefited from spleen- and anal sphincter-sparing procedures
- Enhanced visualization of tumor attachment and neutralization of adhesions improved surgical precision
Treatment Protocol Details
The median treatment duration was 9.9 months, with TKI therapy discontinued immediately before surgery. The study observed a median interval of 51 days between the final response scan and surgical intervention. While the European Society for Medical Oncology recommends six to 12 months of treatment for metastatic GIST, the optimal duration for non-metastatic cases remains under investigation.
Clinical Implications
This pioneering research represents the first comprehensive investigation into the relationship between radiological response criteria and surgical benefits following neoadjuvant treatment in GIST patients. The findings suggest that early assessment of treatment response through CT imaging could help optimize patient selection and treatment planning, potentially leading to improved surgical outcomes in non-metastatic GIST cases.
