5P - Repeated biopsy for mutational analysis on EGFR-mutated non-small cell lung cancer (EGFR-NSCLC): Feasibility and safety

Date 07 May 2017
Event ELCC 2017
Session Poster Display Session
Topics Non-Small-Cell Lung Cancer, Locally Advanced
Non-Small-Cell Lung Cancer, Metastatic
Lung and other Thoracic Tumours
Pathology/Molecular Biology
Presenter Georgia Anguera
Citation Annals of Oncology (2017) 28 (suppl_2): ii1-ii5. 10.1093/annonc/mdx090
Authors G. Anguera1, M. Riudavets2, A. Torrego2, V. Pajares2, A. Gimenez3, L. López-Vilaró3, E. Martínez3, J.C. Trujillo-Reyes3, E. Lerma3, M. Majem3
  • 1Medical Oncology, Hospital de la Santa Creu i Sant Pau, 08026 - Barcelona/ES
  • 2Hospital de la Santa Creu i Sant Pau, Barcelona/ES
  • 3Medical Oncology, Hospital de la Santa Creu i Sant Pau, Barcelona/ES

Abstract

Background

The majority of non-small cell lung cancer (NSCLC) patients (pts) with epidermal growth factor receptor (EGFR) mutation develop resistance to EGFR tyrosine kinase inhibitors, in 50-60% of the cases, mediated by the EGFR T790M-mutation. Repeated biopsy (Bx) is necessary after progression on initial therapy to check T790M status. The aim of this study is to evaluate the feasibility and safety of repeated Bx in clinical practice.

Methods

Retrospective analysis of 110 repeated biopsies (Bxs) performed in 74 pts with advanced NSCLC during the last 4 years, 30 of them with EGFR-NSCLC underwent to 42 Bxs. The technical success rates for the repeated Bx and the adequacy rates of specimens were evaluated. Bx-related complications were recorded. Clinical details were collected.

Results

42 repeated Bxs were performed in 30 pts with EGFR-NSCLC (6 men (20%), 24 women (80%)). Mean age 62 (36-82). Mean number of repeated Bxs per patient: 1 (1-3). At diagnosis (dx), exon 19 mutation was detected in 20 pts (66,7%) and exon 21 mutation in 10 (33,3%). The main reasons for repeated Bx were: mutational analysis at dx 5 (16,7%), insufficient material at dx 4 (13,3%) and detection of T790M at the moment of progression 21 (70%). The technical success rate for Bx was 35/42 (83.3%), and postprocedural complications occurred in 2/42 cases: 1 pneumothorax and 1 low bleeding. Bx specimens came mostly from primary tumor (25/42, 59,5%, followed by: lymph nodes (2/42, 4,8%), pleural fluid (3/42, 7,15%), liquid Bx (3/42, 7,15%), metastasis sites (9/42, 21,4%): bone 2, liver 2, spinal fluid 2, pleural 2, adrenal gland 1. The most used technique was bronchoscopy (19/42, 45,2%), followed by: percutaneous biopsy (11/42, 26,2%), thoracocentesis (4/42, 9,5%). Other techniques: liquid Bx 3 cases (7,15%), surgery 3 (7,15%) and lumbar puncture 2 (4,8%). Results from repeated Bx were used to select the next line of treatment in 28/42 procedures (66,7%), and 16 of them (57,1%) allowed to include the patient in a clinical trial.

Conclusions

Our data demonstrate that repeated Bx in EGFR-NSCLC is safe and clinically feasible. Findings from repeated biopsy were used to direct subsequent treatment in 66.7% of pts and 16 of them (57,1%) allowed to include the patient in a clinical trial.

Clinical trial identification

Legal entity responsible for the study

Hospital de la Santa Creu i Sant Pau

Funding

Hospital de la Santa Creu i Sant Pau

Disclosure

All authors have declared no conflicts of interest.