1311P - Molecular genotyping with high-throughput method, oncomap v4.0 for small biopsy samples in newly diagnosed advanced non-small cell lung cancer patie...

Date 29 September 2012
Event ESMO Congress 2012
Session Poster presentation I
Topics Non-Small-Cell Lung Cancer, Metastatic
Pathology/Molecular Biology
Presenter Chi Hoon Maeng
Authors C.H. Maeng1, M. Ahn2, K. Park3, S.J. Lee4, H.A. Jung5, W. Chang4, S. Park2, M.K. Choi5, Y.S. Kim5, J.Y. Hong5
  • 1Hematology-oncology, Sungkyunkwan University, School of Medicine, 135-710 - Seoul/KR
  • 2Department Of Internal Medicine, Hematology, Oncology, Samsung Medical Center Sungkyunkwan University School of Medicine, 135-710 - Seoul/KR
  • 3Division Of Hematology/oncology, Department Of Medicine, Sungkyunkwan University, School of Medicine, 135-710 - Seoul/KR
  • 4Medicine, Samsung Medical Center, 135-710 - Seoul/KR
  • 5Hematology-oncology, Samsung Medical Center, SEOUL/KR

Abstract

Introduction

With the introduction of molecular targeted agents, mutational analysis of cancer tissue became mainstay of treatment decision making in oncology field. Since lung cancer has the complex and diverse somatic mutations, extensive and fast genetic profiling such as high-throughput molecular genotyping is needed. Given the difficulty in acquisition of adequate tumor tissues for high-throughput molecular genotyping in advanced non-small cell lung cancer (NSCLC), fast and efficient method for detecting various genetic alterations with small biopsy is also required.

Methods and materials

We analyzed tissue specimens obtained from total 64 patients (one specimen per one patient) who were pathologically confirmed with advanced NSCLC. OncoMap v4, a mass-spectrometry based assay, was used to interrogate 471 oncogenic mutations in 41 commonly mutated genes. All of the tumor specimens were prepared from fresh frozen tissue obtained by endobronchial ultrasound or radiologic intervention-guided core biopsy.

Results

In total, we have detected any mutations in 66% of patients (42 out of 64 patients). There were total 59 hotspot mutations out of 64 specimens tested. The most frequent mutation was TP53 mutation (n = 25, 39.1%), followed by EGFR (n = 16, 25.0%), MLH1 (n = 7, 10.9%), KRAS (n = 3, 4.7%), PIK3CA (n = 3, 4,7%), ERBB2 (n = 2, 3.1%), and one case of ABL1 (1.6%) and HRAS (1.6%), respectively. The rate or types of mutation detected are comparable to the results of previous literatures or database such as COSMIC data. Approximately 7-10 days were required to complete primary profiling and assay validation. Among 16 patients who were shown to be postive for EGFR mutation by OncoMap, 3 patients were negative for the mutation test by direct sequencing method. Two patients of positive ERBB2 mutation had very short duration of response to erlotinib (25 days and 26 days, respectively).

Conclusions

These results suggest that molecular genotyping using high-throughput technology such as OncoMap v4 is feasible even with small biopsied specimens from advanced NSCLC patients. This platform can be useful for clinicians to make treatment decision based on molecular genotyping in daily clinical practice.

Disclosure

All authors have declared no conflicts of interest.