Relationship Between Dose and Local Control in Five-fraction Stereotactic Body Radiotherapy for Hepatocellular...

Area of Science:

• Radiation Oncology
• Hepatocellular Carcinoma Research
• Clinical Dosimetry

Background:

• Stereotactic body radiotherapy (SBRT) is an effective treatment for hepatocellular carcinoma (HCC).
• Optimizing radiation dose delivery is critical for achieving local control (LC) and minimizing toxicity in HCC patients treated with SBRT.
• The minimum dose covering 95% of the planning target volume (PTV D95%) is a key dosimetric parameter that may influence treatment outcomes.

Purpose of the Study:

• To investigate the association between the planning target volume (PTV D95%) and local control (LC) in patients with hepatocellular carcinoma (HCC) treated with SBRT.
• To identify an optimal PTV D95% threshold for preventing local recurrence in HCC patients.

Main Methods:

• Retrospective analysis of 72 HCC tumors in 59 patients treated with five-fraction SBRT (30-50 Gy).
• Evaluation of local control (LC) rates and correlation with the minimum dose covering 95% of the planning target volume (PTV D95%).
• Univariate, multivariate, and receiver operating characteristic (ROC) analyses were performed to determine the prognostic significance of PTV D95%.

Main Results:

• The median follow-up was 20 months, with a 1-year LC rate of 93.7% and a 2-year LC rate of 82.3%.
• PTV D95% was a significant prognostic factor for LC in both univariate and multivariate analyses (p<0.05).
• No local recurrences were observed in patients receiving PTV D95% ≥40 Gy, and 38 Gy was identified as the optimal cut-off dose to prevent recurrence.

Conclusions:

• The minimum dose covering 95% of the planning target volume (PTV D95%) is a significant predictor of local control (LC) in HCC patients treated with SBRT.
• A PTV D95% of 40 Gy or higher is recommended as a target dose to improve local control and prevent recurrence in HCC patients treated with five-fraction SBRT.