1255P - Population based evaluation of chemotherapy use after first line gefitinib in epidermal growth factor receptor (EGFR) mutation positive advanced non...

Date 29 September 2012
Event ESMO Congress 2012
Session Poster presentation I
Topics Anti-Cancer Agents & Biologic Therapy
Non-Small-Cell Lung Cancer, Metastatic
Presenter Caroline Mariano
Authors C. Mariano1, I. Bosdet2, D. Ionescu3, A. Karsan3, S. Sun1, N. Murray1, B. Melosky1, J. Laskin1, C. Ho1
  • 1Medical Oncology, British Columbia Cancer Agency, vancouver/CA
  • 2Cancer Genetics, British Columbia Cancer Agency, Vancouver/CA
  • 3Pathology, British Columbia Cancer Agency, vancouver/CA

Abstract

Introduction

The IPASS trial demonstrated superior progression free survival for Asian, light/never smoking, advanced, adenocarcinoma patients treated with first line Gefitinib compared to carboplatin/paclitaxel, of which 59% of those tested were EGFR mutation positive (MUT+). In IPASS 39% of Gefitinib treated patients went on to receive platin based therapy. We hypothesize that in a population-based setting fewer patients receive second line platin based chemotherapy.

Methods

The Iressa Alliance Program provided standardized EGFR mutation testing and appropriate access to Gefitinib to all patients in British Columbia (population 4.5 million) with advanced, non squamous NSCLC. EGFR mutation testing was limited to the most common mutations; exon 19 and 21. We retrospectively analyzed clinical, pathologic and outcomes for all patients tested in this program between March 2010 and June 2011.

Results

A total of 548 patients were referred for testing and 107 (19%) patients were MUT+. Baseline characteristics of MUT- and MUT + ; median age 67/65, male 41%/31%, Asian 15%/51%, never smoker 21%/58%, stage IV 80%/91%. Overall survival was 10.9 versus 14.9 months (p < 0.0001). In MUT + patients treated with first line Gefitinib average duration of therapy was 312 days. 5% of patients had a CR, 43% PR, 34% SD, 5% PD with 12% not evaluable. 23% of patients continued on Gefitinib after radiographic progression. 51 Gefitinib treated patients progressed at the time of analysis; 15% of patients received Gefitinib only, 33% platin based doublet, 10% other chemotherapy and 42% no further treatment. Five patients received 3rd line therapy.

Conclusions

This North American population based study shows similar efficacy of Gefitinib in MUT+ patients compared to the IPASS trial. Clinicians often continued Gefitinib past progression, likely due to ongoing clinical benefit. Contrary to our hypothesis, delivery of second line chemotherapy was feasible in a significant proportion of Gefitinib treated patients, similar to results seen in clinical trials. MUT+ patients have a better prognosis and this may contribute to their ability to receive further therapy.

Disclosure

All authors have declared no conflicts of interest.