HCC Tumor Burden Score Predicts Long-Term Outcomes Following MWA

Radiographic tumor burden score (TBS) appears to be a meaningful predictor of long-term outcomes in patients with hepatocellular carcinoma (HCC) who meet Milan criteria following microwave ablation (MWA), a new study found.1 The study, published in the journal Cancer Medicine, found a higher TBS score was associated with lower long-term survival rates.

The authors noted that while surgical resection is considered the most effective treatment for HCC, alternative options like MWA are necessary due to their superior safety and precision and the lower level of trauma associated with the procedure. Yet, outcomes following MWA vary significantly, and the existing models of predicting response to MWA are insufficient, they wrote.

The report suggests a TBS cutoff value of 3 will serve as a meaningful prognostic tool in HCC, but differences in patient populations and imaging techniques may affect the value of that cutoff, the authors noted. | Image credit: Jo Panuwat D - stock.adobe.com

One possible solution is radiographic TBS, a technique first reported in 2018 as a prognostic indicator for people with colorectal liver metastasis.2 Since then, the tool has been used in a number of liver cancer applications, but it has not yet been evaluated as a predictor of post-MWA prognosis in HCC.1

To determine its value in HCC prognostication, the authors pulled clinical data from 198 patients with HCC who met Milan criteria and underwent MWA between 2011 and 2018. The investigators used X-tile software to categorize patients into low- and high-TBS groups. They then used propensity score matching to balance covariates between the groups.

After propensity-score matching, the 5-year overall survival (OS) rate in the 44 high-TBS patients was 30.2%, compared to 64.1% (P = .011) for the 95 low-TBS patients, and the recurrence-free survival (RFS) rate was 21.9% in the high-TBS group, versus 45.9% in the low-TBS group (P = .0059). Cox analysis suggested high TBS and percutaneous MWA were independent risk factors for both OS and RFS. The median RFS for patients in the high-TBS cohort was 45 months for those undergoing laparoscopic MWA (20 cases) and 10.5 months for patients undergoing percutaneous MWA (24 cases; P = .006).

“Our study revealed a positive correlation between high TBS and increased local recurrence rates, coupled with a decrease in long-term survival rates,” the investigators said.

The authors cited several reasons why laparoscopic MWA outperformed percutaneous. Among the reasons, they said it tends to enable the identification of small lesions and is performed under general—rather than local—anesthesia. The latter point ensures a more thorough effect due to better patient cooperation.

The authors cited a number of limitations to their findings. It was retrospective in nature and involved a relatively small high-TBS sample size. They said a broader study with multiple centers and more patients would enable a more reliable validation of the TBS prediction model.

However, they said the simplicity of TBS, which relies on ultrasound and thus can be performed even in relatively under-resourced settings, makes it an attractive resource for clinical practice.

The authors concluded their report suggests a TBS cutoff value of 3 will serve as a meaningful prognostic tool. They added, though, that differences in patient populations and imaging techniques may affect the value of that cutoff, underscoring the need for additional study. In the meantime, they said clinicians should use TBS results alongside other clinical factors as they assess the right treatment path for particular patients.

References

1. Liu X, Wang J, Xu F, Chen J, Zhu M, Wang X. Predictive value of radiographic tumor burden score in hepatocellular carcinoma within Milan criteria after microwave ablation: implications for long-term outcomes and treatment planning. Cancer Med. 2025;14(9):e70806. doi:10.1002/cam4.70806
2. Sasaki K, Morioka D, Conci S, et al. The tumor burden score: a new "metro-ticket" prognostic tool for colorectal liver metastases based on tumor size and number of tumors. Ann Surg. 2018;267(1):132-141. doi:10.1097/SLA.0000000000002064