Objectives: Gastrointestinal stromal tumor (GIST) liver metastasis (GLM) is a special subset of advanced GIST, because its lesions are easier to define and assess. We aim to determine the role of liver metastasectomy for patients with GLM in the era of tyrosine kinase inhibitor (TKI) therapy.
Methods: We reviewed patients with metastatic GIST who received surgery or other treatments in Sun Yat-sen University Cancer Center between January 1991 and December 2017. Patients with metastases confined to the liver and with no previous metastasis to other locations were included into the study and were classified into surgical and non-surgical groups. All patients received 400  mg/d imatinib after the operation. We compared progression-free survival (PFS) and overall survival (OS) between the two groups.
Results: A total of 102 patients were included into the study. Of them, 21 (20.1%) underwent surgery for liver metastases and 81 (79.9%) received TKI therapy alone. During the operation, six patients received radiofrequency ablation for suspicious or unresectable lesions. Three-year PFS rate was 77.5% in the surgical group and 65.5% in the non-surgical group (P =0.027); 5-year OS rate was 85.7% and 59.6%, respectively (P =0.008). About 22.1% of patients had metastases of less than three in the surgical group, while the rate was 42.9% in the non-surgical group (P =0.011). Patients with metastases of less than three had longer PFS than those with three or more, with a 3-year PFS rate of 72.8% and 65.8%, respectively (P =0.019). But their difference in 5-year OS rate was not significant (91.7% vs 55.3%, P =0.08).
Conclusion: Followed by continuous TKI therapy, R0 surgery significantly prolongs the survival of patients with GLM, regardless of the extent of disease or the phase of metastasis.
Keywords: gastrointestinal stromal tumor, liver metastasis, surgery, metastasectomy