A role for adjuvant RFA in managing hepatic metastases from gastrointestinal stromal tumors (GIST) after treatment with targeted systemic therapy using kinase inhibitors.

Hakimé, Antoine; Le Cesne, Axel; Deschamps, Frederic; Farouil, Geoffroy; Boudabous, Sana; Aupérin, Anne; Domont, Julien; Debaere, Thierry

PURPOSE This study was designed to assess the role of radiofrequency ablation (RFA) in the multimodality management of gastrointestinal stromal tumors (GIST) in patients undergoing targeted tyrosine kinase inhibitor therapy (TKI) for liver metastases. METHODS Outcomes of 17 patients who underwent liver RFA for 27 metastatic GIST after TKI therapy, from January 2004 to March 2012, were retrospectively analyzed. Mean maximum tumor diameter was 2.5 ± 1 cm (range 0.9-4.5 cm). In seven patients (group A), RFA of all residual tumors was performed, with curative intent, and TKI therapy was discontinued. In five patients (group B), RFA of all residual tumors was performed upon achieving the best morphological response with TKI therapy, which was maintained after RFA. In another five patients (group C), RFA was performed on individual liver metastases which were progressive under TKI therapy. RESULTS All 27 targeted tumors were completely ablated, without local recurrence during the mean follow-up period of 49 months. No major complications occurred. Two minor complications were reported (11 %). Only two patients (both in group C) died at 20 and 48 months. Two-year progression-free survival (PFS) after RFA was 29 % in group A, 75 % in group B, and 20 % in group C. CONCLUSIONS RFA in patients, previously treated with TKI, is feasible and safe. Our data suggest that RFA is a useful therapeutic option in patients with metastatic GIST and should be performed at the time of best clinical response with patient maintained under TKI after the procedure.