Referral patterns in advanced non-small cell lung cancer: impact on delivery of treatment and survival in a contemporary population based cohort

Abstract

Introduction: Chemotherapy improves overall survival (OS) in advanced non-small cell lung cancer (NSCLC), yet low rates of chemotherapy utilization have been observed. We sought to characterize the clinical effectiveness of chemotherapy in the general population by evaluating referral patterns, predictors of chemotherapy receipt and outcomes.

Methods: All referred cases of stage IIIB/IV NSCLC in British Columbia from January 1 to December 31, 2009 were retrospectively reviewed. Patient demographics, tumor characteristics and treatments were extracted. OS was estimated using the Kaplan-Meier method. Cox Proportional Hazards modeling was used to control for confounding variables. Multiple logistic regression was used to assess factors that predicted for chemotherapy treatment.

Results: 1373 patients were identified. Median age 70 years, 53% male, 37% ECOG ≥ 3.

Histology: 34% non-squamous, 21% squamous and 46% NOS. 748 (54%) patients were assessed by medical oncology and 417 (30%) received chemotherapy. Predictors of chemotherapy treatment were younger age, ECOG 0-2, living in a rural area and not receiving radiotherapy. There was an improvement in OS in patients who received chemotherapy at 13.1 months versus best supportive care 5.4 months (p<0.0001). This remained statistically significant when controlling for ECOG, sex, age, histology (HR 0.68, CI 0.59-0.78).

Conclusions: In this population-based setting, 37% of patients had an ECOG ≥ 3 at the time of referral, 54% were assessed by a medical oncologist and only 30% received chemotherapy. This is despite the awareness that chemotherapy significantly improves survival. Strategies to optimize appropriate referral such that patients do not miss out on life-prolonging therapy should be evaluated.

Keywords: Advanced NSCLC; Population-based analysis; Referral patterns; Treatment delivery.