Stereotactic body radiation therapy for liver oligo-recurrence and oligo-progression from various tumors

Abstract

Purpose: To evaluate the outcomes of stereotactic body radiation therapy (SBRT) for patients with liver oligo-recurrence and oligo-progression from various primary tumors.

Materials and methods: Between 2002 and 2013, 72 patients with liver oligo-recurrence (oligo-metastasis with a controlled primary tumor) and oligo-progression (contradictory progression of a few sites of disease despite an overall tumor burden response to therapy) underwent SBRT. Of these, 9 and 8 patients with uncontrollable distant metastases and patients immediate loss to follow-up, respectively, were excluded. The total planning target volume was used to select the SBRT dose (median, 48 Gy; range, 30 to 60 Gy, 3-4 fractions). Toxicity was evaluated using the Common Toxicity Criteria for Adverse Events v4.0.

Results: We evaluated 55 patients (77 lesions) treated with SBRT for liver metastases. All patients had controlled primary lesions, and 28 patients had stable lesions at another site (oligo-progression). The most common primary site was the colon (36 patients), followed by the stomach (6 patients) and other sites (13 patients). The 2-year local control and progression-free survival rates were 68% and 22%, respectively. The 2- and 5-year overall survival rates were 56% and 20%, respectively. The most common adverse events were grade 1-2 fatigue, nausea, and vomiting; no grade ≥3 toxicities were observed. Univariate analysis revealed that oligo-progression associated with poor survival.

Conclusion: SBRT for liver oligo-recurrence and oligo-progression appears safe, with similar local control rates. For liver oligo-progression, criteria are needed to select patients in whom improved overall survival can be expected through SBRT.

Keywords: Liver metastases; Oligo-progression; Oligo-recurrence; Stereotactic radiation therapy.

Fig. 1.

Stereotactic body radiation therapy outcomes. (A) Local control rate. (B) Progression-free survival. (C) Overall survival. The bold black lines represent the overall rates. The blue and green lines represent the rates for patients with oligo-recurrence and oligo-progression, respectively.

Fig. 2.

Failure patterns in patients with oligo-recurrence and oligo-progression. (A) Failure patients among patients with no extra-hepatic lesion (oligo-recurrence) treated by SBRT (14/27 patients). (B) Failure patients among the patients with an extrahepatic (oligo-progression) treated by SBRT (24/28 patients). SBRT, stereotactic body radiation therapy; LR, local recurrence (recurrence within the field that received SBRT); IHR, intra-hepatic recurrence (recurrence outside the field that received SBRT, but not extra-hepatic recurrence); EHR, extra-hepatic recurrence (recurrence outside the liver, including progression of extrahepatic inactive lesions present during SBRT).