Elisna Syahruddin, Laksmi Wulandari, Nunuk Sri Muktiati, Ana Rima, Noni Soeroso, Sabrina Ermayanti, Michael Levi, Heriawaty Hidajat, Grace Widjajahakim, Ahmad Rusdan Handoyo Utomo
Purpose: We aimed to evaluate the distribution of individual epidermal growth factor receptor (EGFR) mutation subtypes found in routine cytological specimens. Patients and methods: A retrospective audit was performed on EGFR testing results of 1,874 consecutive cytological samples of newly diagnosed or treatment-naïve Indonesian lung cancer patients (years 2015–2016). Testing was performed by ISO15189 accredited central laboratory. Results: Overall test failure rate was 5.1%, with the highest failure (7.1%) observed in pleural effusion and lowest (1.6%) in needle aspiration samples. EGFR mutation frequency was 44.4%. Tyrosine kinase inhibitor (TKI)-sensitive common EGFR mutations (ins/dels exon 19, L858R) and uncommon mutations (G719X, T790M, L861Q) contributed 57.1% and 29%, respectively. Approximately 13.9% of mutation-positive patients carried a mixture of common and uncommon mutations. Women had higher EGFR mutation rate (52.9%) vs men (39.1%; p<0.05). In contrast, uncommon mutations conferring either TKI responsive (G719X, L861Q) or TKI resistance (T790M, exon 20 insertions) were consistently more frequent in men than in women (67.3% vs 32.7% or 69.4% vs 30.6%; p<0.05). Up to 10% EGFR mutation–positive patients had baseline single mutation T790M, exon 20 insertion, or in coexistence with TKI-sensitive mutations. Up to 9% patients had complex or multiple EGFR mutations, whereby 48.7% patients harbored TKI-resistant mutations. One patient presented third-generation TKI-resistant mutation L792F simultaneously with T790M. Conclusion: Routine diagnostic cytological techniques yielded similar success rate to detect EGFR mutations. Uncommon EGFR mutations were frequent events in Indonesian lung cancer patients. © 2018 Syahruddin et al.
Department of Pulmonology and Respiratory Medicine, Faculty of Medicine, Universitas Indonesia, Indonesia; Department of Pulmonology, Persahabatan Hospital, Jakarta, Indonesia; Department of Pulmonology and Respiratory Medicine, Faculty of Medicine, Universitas Airlangga – Soetomo Hospital, Surabaya, Indonesia; Department of Pulmonology and Respiratory Medicine, Faculty of Medicine, Universitas Brawijaya – Saiful Anwar General Hospital, Malang, Indonesia; Department of Pulmonology and Respiratory Medicine, Faculty of Medicine, Universitas Sebelas Maret, Dr. Moewardi General Hospital, Surakarta, Indonesia; Department of Pulmonology and Respiratory Medicine, Faculty of Medicine, University of Sumatera Utara, Adam Malik General Hospital, Medan, Indonesia; Department of Pulmonology and Respiratory Medicine, Faculty of Medicine, Andalas University, M. Djamil Hospital, Padang, Indonesia; Kalbe Genomics Laboratory, Division of Molecular Pathology Testing Service, PT Bifarma Adiluhung, Indonesia; Stem Cell and Cancer Institute, Cancer Diagnostic Research Division, PT Kalbe Farma Tbk, Jakarta, Indonesia
