2031 - Stereotactic Central/Core Ablative Radiation Therapy (SCART) for Hepatic Tumors: A Single-Institution Case Series of 95 Patients
Presenter(s)
B. Chen1, W. Yan2,3, Y. Li1, X. Shi1, J. Song4, X. Lv1, Y. Zhou1, P. Tang1, and J. Yang3,4; 1Foshan Fosun Chancheng Hospital, Foshan, Guangdong, China, 2College of Medicine, University of Kentucky, Lexington, KY, 3Azure Research Institute, Richmond, KY, 4Junxin Oncology Institute, Foshan, Guangdong, China
Purpose/Objective(s): Managing large or multifocal liver tumors—whether primary (HCC, ICC) or metastatic—remains a significant clinical challenge. In many cases, the sheer size of the disease precludes conventional stereotactic body radiation therapy (SBRT) because of the high risk to healthy liver tissue. Stereotactic Central/Core Ablative Radiation Therapy (SCART) offers a workaround: it delivers a high, ablative dose to a small "core" target (STV) within the tumor while intentionally maintaining a lower dose at the tumor boundary to spare the surrounding liver. In this study, we report the outcomes of 95 patients treated with this approach at our institution.
Materials/Methods: We retrospectively reviewed consecutive patients who underwent hepatic SCART between 2020 and 2025. Our planning strategy typically prescribed 15–24 Gy per fraction to the central STV, while limiting the dose at the gross tumor volume (GTV) boundary to approximately 5 Gy per fraction. We tracked overall survival (OS) from the date of the first SCART treatment using the Kaplan-Meier method and assessed volumetric response based on the percentage change in tumor size at the first post-treatment scan.
Results:
The cohort consisted of 95 patients (median age 63; 72% male) who received a total of 125 SCART courses. The disease profile was diverse, with 47% of patients treated for primary liver cancers and 53% for metastases (most commonly colorectal, lung, and pancreatic). These were largely advanced cases; 67% had stage IV disease, and the median tumor volume (GTV) was a substantial 415 cm³. Despite these large volumes, the targeted ablative core (STV) remained small, with a median STV/GTV ratio of just 5.5%.
The most frequent treatment regimen was 21 Gy across three fractions (56%), and nearly 80% of patients remained on concurrent systemic therapy. Among the 93 evaluable patients (63 deaths), the median OS was 9.1 months, with 12- and 24-month survival rates of 40% and 22%, respectively. Radiographic outcomes were particularly encouraging: 88% of tumors had shrunk by the first follow-up (median reduction of 35%), and 71% of patients eventually achieved a volume decrease of more than 30%.
Conclusion: Our experience suggests that SCART is a feasible and effective option for patients with large, advanced hepatic tumors that exceed the traditional limits of SBRT. By focusing ablative doses on the tumor core, we achieved high rates of tumor shrinkage even in very high-volume disease. This partial-volume approach provides a viable treatment path for patients with limited options, though prospective studies are now needed to standardize toxicity reporting and long-term local control.