Abstract
Background: With the evolution of individualised treatment strategies in non small cell lung cancer (NSCLC), it is becoming increasingly important to obtain adequate tissue for accurate pathologic sub-typing and molecular testing. In most cases diagnosis and staging is done using small biopsies or cytology specimens obtained by minimally invasive techniques.
Aim: To compare the adequacy of cytology and histology samples used for epidermal growth factor receptor (EGFR) mutation screening.
Methods: Retrospective study of 135 consecutive samples obtained from NSCLC patients between Jan 2010 and Dec 2011.
Results: Of the 135 samples sent for EGFR testing, 13 were positive, 115 negative and 7 were considered inadequate or failed molecular testing. 106 had adenocarcinoma, 11 adenosquamous, 13 NSCLC-NOS(not otherwise specified), 4 squamous and 1 small cell. Positive EGFR was noted in 4 cytology and 9 histology samples (p=0.27).
Cytology samples include 46 endobronchial ultrasound (EBUS) guided fine needle aspiration (FNA), 8 pleural fluid, 7 ultrasound guided or superficial FNAs from lymph nodes or masses, 1 transbronchial (mini-probe), 2 bronchial washings and 2 brush biopsies. Histology biopsies include 29 endobronchial biopsies, 19 CT guided lung biopsies, 8 thoracoscopic and 1 ultrasound guided pleural biopsies, 1 renal biopsy, and 11 surgical excision samples (bone, brain, lymph node and groin mass).
Conclusion: The overall adequacy rate from both groups was 95% with no difference, suggesting that the cytology samples can be reliably used for molecular testing.
- © 2012 ERS
