116P - Clinical characteristics and response to EGFR TKI in never smoker squamous lung cancer

Date 17 April 2015
Event ELCC 2015
Session Poster lunch
Topics Anti-Cancer Agents & Biologic Therapy
Non-Small-Cell Lung Cancer, Metastatic
Presenter Samuel Ee
Citation Annals of Oncology (2015) 26 (suppl_1): 29-44. 10.1093/annonc/mdv050
Authors S. Ee1, S. Young1, E.H. Tan1, D. Lim1, G.S. Tan2, A. Jain1, W. Zeng3, T. Lim2, A. Takano2, D. Tan1
  • 1Medical Oncology, National Cancer Center, 169610 - Singapore/SG
  • 2Department Of Pathology, Singapore General Hospital, Singapore/SG
  • 3Duke-nus Graduate Medical School, Duke-NUS Graduate Medical School, Singapore/SG



Although Epidermal Growth Factor Receptor (EGFR) mutations and response to EGFR tyrosine kinase inhibitors (TKIs) are established in patients with lung adenocarcinoma, its efficacy in squamous cell histology–particularly those with no smoking history–is less well defined. We describe a retrospective series of never smoker squamous cell carcinoma (SCC) and their treatment response to EGFR TKI.


From a prospectively collated database maintained by the Lung Cancer Consortium Singapore, 18 never-smokers with SCC who received TKIs as a treatment line were identified. In patients with sufficient tissue, thorough histological review and immunohistochemistry (TTF1, p40) was performed by a thoracic pathologist, and sequenced for EGFR mutations. Patients with measurable disease were evaluated using RECIST criteria.


Median age of patients was 53 (range 32 - 70), male:female (7:11) and 13 were stage IV at diagnosis, 5 were stage III. Histologic re-evaluation confirmed the diagnosis of SCC in 14 patients, while 3 were re-classified as having mixed adenocarcinoma (n = 1), and poorly differentiated adenocarcinoma (n = 2, TTF1 +, p40 negative). 1 patient had no available tissue for re-evaluation. Of the 14 patients with SCC, 6 (43%) were found to harbor EGFR sensitizing mutations (Exon 19 deletion [4], L858R [1], G719A [1]) by Sanger sequencing. 12 out 15 patients started on EGFR TKIs were evaluable for response. Overall response rate (ORR) was 23.1%, with a disease control rate of 53.8%. Median progression free survival on an EGFR TKI was 2.3 months and median overall survival was 19.4 months. Either partial or complete response was observed in 2 of the 6 patients with sensitizing mutations, while none of the patients without mutations responded.


Never smoker SCC represent a unique subset of lung cancer that have a favourable median overall survival of 19.4 months. In our series, 43% (6/14) were found to harbour EGFR mutations, and where responses to EGFR TKI were primarily observed.


All authors have declared no conflicts of interest.