Journal of Medical Cases, ISSN 1923-4155 print, 1923-4163 online, Open Access
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Case Report

Volume 12, Number 8, August 2021, pages 310-314

Transformation From Adenocarcinoma to Pleomorphic Carcinoma as an Acquired Resistance to Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitors

Figures

Figure 1.
Figure 1. Chest CT scan (a) at the diagnosis, (b) 3 months after the initiation of gefitinib, and (c) at the second re-biopsy after resistance to EGFR-TKIs. CT: computed tomography; EGFR-TKI: epidermal growth factor receptor tyrosine kinase inhibitor.
Figure 2.
Figure 2. The first transbronchial biopsy specimen at the diagnosis shows adenocarcinoma: (a) hematoxylin and eosin staining (× 20) and (b) staining by anti-EGFR exon 21 specific antibody (× 10). EGFR: epidermal growth factor receptor.
Figure 3.
Figure 3. The second transbronchial re-biopsy specimen after resistance to EGFR-TKIs: (a) hematoxylin and eosin staining (× 20) and (b) staining by anti-EGFR exon 21 specific antibody (× 10). EGFR-TKI: epidermal growth factor receptor tyrosine kinase inhibitor.

Table

Table 1. Summary of Previous Cases of Histological Changes From Adenocarcinoma to Pleomorphic Carcinoma After EGFR-TKIs
 
Authors (year)Age, sex, smokingEGFR-TKI (response, TTP)OSEGFR mt at diagnosis (specimens)PPC diagnosis
SpecimensCarcinomatous EGFR mt expressionSarcomatous EGFR mt expression
Adeno: adenocarcinoma; BFS: bronchoscopy; CS: current smoker; EGFR-TKI: epidermal growth factor receptor tyrosine kinase inhibitor; F: female; LN: lymph node; M: male; met: metastasis; mt: mutation; ND: not described; NS: non-smoker; OS: overall survival; PD: progressive disease; PPC: pulmonary pleomorphic carcinoma; PR: partial response; SD: stable disease; TTP: time to progression.
Ushiki et al (2009) [6]58, M, NSGefitinib (PD, 3 months)4 monthsEx19 del (neck LN, pleural effusion)AutopsyAdenocarcinoma Ex19del(+)Spindle Ex19del(+), T790M(+)
Toda-Ishii et al (2015) [8]78, F, NSGefitinib (SD, ND)NDL858R (lung)Biopsy (femur met)Not detectedSpindle ND
Masuda et al (2018) [7]65, F, NSErlotinib (PD, 12 days)15 daysL858R (lung)AutopsyAdenocarcinoma L858R(+)Spindle L858R(-)
Ours65, F, CSGefitinib, erlotinib (PR, 9 months)23 monthsL858R (lung)BFSAdenocarcinoma L858R(+)Spindle L858R(+)