Clinical outcomes of extensive stage small cell lung carcinoma patients treated with consolidative thoracic radiotherapy

Abstract

The purpose of this review was to determine the effect of consolidative thoracic radiotherapy (TRT) in patients with extensive stage small cell lung cancer (ES-SCLC) with minimal metastatic disease. Locoregional failure, distant failure and OS were 39%, 74% and 14% respectively at 2 years. No patients experienced clinical pneumonitis. Consolidative TRT is well tolerated in selected patients with ES-SCLC.

Objectives: To determine the rates of loco-regional (LR) failure and toxicity in extensive-stage small cell lung carcinoma (ES-SCLC) patients treated with consolidative thoracic radiotherapy (TRT).

Methods: A retrospective review was conducted on SCLC patients treated from January 2005 to July 2009. Patients with ES-SCLC who received consolidative TRT ≥30Gy were identified. Sites of disease failure, toxicity Common Terminology Criteria for Adverse Events version 3.0, incidence, and cause of treatment delays and vital status were determined. The cumulative LR and distant failure rates were calculated. Progression-free and overall survivals (OS) were determined by the Kaplan-Meier method.

Results: Three hundred thirty-six patients were identified with a diagnosis of SCLC and 215 patients had ES-SCLC. Nineteen (9%) patients were identified as receiving ≥30Gy consolidative TRT. Of this subgroup, the median age was 60 years (range 47 years to 82 years) and the median follow-up was 13 months (range 8 months to 32 months). Consolidative TRT was 40Gy/15 fractions (n = 16), 45Gy/30 fractions delivered twice daily (n = 2) and 36Gy/12 fractions (n = 1). Chemotherapy was sequential (n = 11) or concurrent (n = 8) with consolidative TRT. The incidence of LR failure was 26% and 39% at 1 and 2 years, respectively. The incidence of distant failure was 58% and 74% at 1 and 2 years, respectively. The median OS was 14 months. The 1-year and 2-year OS was 58% and 14%, respectively. No patients experienced clinical pneumonitis requiring treatment.

Conclusions: Consolidative TRT controlled LR disease in most patients with minimal acute toxicity, though distant failure remained a significant problem.