Ablation With Systemic Therapy vs Liver Resection With Systemic Therapy for Colorectal Liver Metastasis

Outcomes of Ablation With Systemic Therapy vs Liver Resection With Systemic Therapy in Colorectal Liver Metastasis: A Multi-center Retrospective Cohort Study

For patients with colorectal liver metastases (CRLM) ≤5 cm, Clinical guidelines recommend surgery, but a growing number of studies have shown that thermal ablation is as effective as surgery. However, the optimal treatment strategy remains unclear.This study aimed to compare outcomes between patients who underwent ablation with systemic therapy or liver resection with systemic therapy for CRLM less than 5 cm in diameter.

Currently, the multidisciplinary team (MDT) model is recommended for the treatment of colorectal liver metastases in clinical practice, with personalized treatment goals and comprehensive treatment to achieve a tumor-free state. For liver metastases that are initially curable, surgical treatment should be performed in a timely manner. Although there are some controversies, surgical resection combined with systemic therapy is still considered the standard treatment . Liver resection alone may not be able to achieve complete cure, while preoperative systemic therapy can help eradicate micro-metastases, and postoperative systemic therapy can reduce the recurrence rate.For liver metastases that are initially unresectable, some lesions can be converted to resectable lesions through systemic therapy with or without targeted therapy. Recently, a phase Ⅲ randomized controlled clinical trial showed that thermal ablation and surgical resection achieve similar overall survival and progression-free survival for patients with resectable CRLM of 3 cm or less in diameter. However, for CRLM of 5 cm or less in diameter, the optimal treatment strategy remains unclear.

Therefore, this study aimed to compare the progression-free survival (PFS), overall survival (OS), and local recurrence rate (LRR) between patients with CRLM less than 5 cm in diameter who underwent ultrasound-guided ablation with systemic therapy and liver resection with systemic therapy.

Inclusion Criteria:

• Age between 18 and 85 years.
• Primary tumor resected with R0 resection and pathological confirmation of colorectal adenocarcinoma.
• Liver metastasis confirmed by any two of the following examinations: contrast-enhanced CT, enhanced MRI, CEUS, PET-CT, or pathology.
• Liver metastases with maximum diameter ≤ 5 cm and ≤ 5 lesions.

Exclusion Criteria:

• History of other local treatments for liver metastasis prior to ultrasound-guided microwave ablation/liver resection.
• With concurrent extrahepatic metastases.
• With concurrent other malignancies.
• With incomplete clinical data.