Biomed Pap Med Fac Univ Palacky Olomouc Czech Repub. 2022, 166(3):274-279 | DOI: 10.5507/bp.2022.007

A rare epidermal growth factor receptor (EGFR) gene mutation in small cell lung carcinoma patients

Cheng-Cheng Hwang^{a, b}, Tsan-Yu Hsieh^{a, b}, Kun-Yang Yeh^{b, c}, Tzu-Ping Chen^{b, d}, Chung-Ching Hua^{b, e}, Liang-Che Chang^{a, b}, Jim-Ray Chen^{a, b}

^a Department of Pathology, Keelung Chang Gung Memorial Hospital, Keelung, Taiwan

^b College of Medicine, Chang Gung University, Kwei-Shan, Taoyuan, Taiwan

^c Department of Oncology and Hematology, Division of Medicine, Keelung Chang Gung Memorial Hospital, Keelung, Taiwan

^d Department of Thoracic and Cardiovascular Surgery, Keelung Chang Gung Memorial Hospital, Keelung, Taiwan

^e Department of Thoracic Medicine, Division of Medicine, Keelung Chang Gung Memorial Hospital, Keelung, Taiwan

Aim: Activating mutations in the epidermal growth factor receptor (EGFR) are predominantly detected in pulmonary adenocarcinoma and have been reported in small cell lung cancer (SCLC) for decades. This retrospective single-center study aimed to determine the frequency and types of EGFR mutations in SCLC in Taiwan.

Methods: This study comprises a consecutive cohort of 161 patients histologically diagnosed with SCLC between January 1992 and August 2014 at the Department of Pathology in Keelung Chang Gung Memorial Hospital, Taiwan. Archived formalin-fixed paraffin-embedded sections from 71 patients were eligible for molecular analysis. EGFR mutation analysis was performed using a fully-automated IdyllaTM EGFR Mutation Test and confirmed a comparable result through Qiagen Therascreen® EGFR RGQ PCR. In addition, EGFR gene copy number was assessed in EGFR-mutated tumors by fluorescence in situ hybridization (FISH).

Results: Mutational status of the EGFR gene was successfully analyzed in 63 specimens by both IdyllaTM and Qiagen platforms. Both methods detected L858R point mutation in exon 21 in an 81-year-old female and a 47-year-old male non-smoker. Both tumors show no concurrent EGFR gene amplification. The overall agreement between results obtained with the Idylla™ EGFR Mutation Test and Qiagen Therascreen® EGFR RGQ PCR was 100% Conclusions. Our results showed that EGFR mutation is a rare mutation type in a consecutive series of de novo SCLC. Furthermore, the performance of Idylla™ EGFR Mutation Test and Qiagen Therascreen® EGFR RGQ PCR on archived paraffin sections of limited quantities is available with the high agreement of results.

Keywords: small cell lung cancer, epidermal growth factor receptor, gene mutation, gene amplification, Idylla^TM

Received: December 8, 2021; Revised: January 21, 2022; Accepted: February 7, 2022; Prepublished online: February 18, 2022; Published: September 14, 2022  Show citation