Prognostic value of gross tumor volume for definitive radiation therapy in patients with locoregionally recurrent non-small-cell lung cancer after surgical resection

Abstract

Purpose: To investigate the prognostic value of gross tumor volume (GTV) for predicting survival outcomes and to present the results of definitive radiation therapy (RT) in patients with postsurgical locoregionally recurrent non-small-cell lung cancer (NSCLC).

Materials and methods: Between April 2001 and September 2009, 38 patients with postsurgical locoregionally recurrent NSCLC underwent definitive RT with curative intent. Median follow-up time for surviving patients was 54.9 months. The primary endpoint was postrecurrence overall survival (OS). The effect of tumor volume on clinical outcome was assessed by using 2 cutoff values of GTV, 20 and 80 cm(3).

Results: Median postrecurrence survival time was 27.9 months, and the 2-, 3-, and 5-year estimated OS rates were 56.0%, 39.8% and 33.2%, respectively. The median GTV was 26.8 cm(3). Patients with a GTV <20 cm(3) had significantly higher 2-year (69.0% vs. 28.6%) and 3-year (61.4% vs. 14.3%) OS rates than patients with a GTV ≥80 cm(3) (P = .004). Patients with isolated local or regional recurrence had significantly better OS than patients with combined local and regional recurrence (P = .001). Multivariate analysis showed that smaller GTV and isolated local or regional recurrence were independent favorable prognostic factors for OS.

Conclusions: Postrecurrence OS of patients with postsurgical locoregionally recurrent NSCLC treated with definitive RT was excellent compared with previous findings. The GTV as a continuous variable was a better predictor of OS than stage at recurrence and may be useful for stratifying the risk in patients with postsurgical recurrent NSCLC.