Significant benefits of osimertinib in treating acquired resistance to first-generation EGFR-TKIs in lung squamous cell cancer: A case report

Figure 1 Baseline imaging examinations. Primary cancer in the inferior lobe of the left lung (A, arrow) with metastases to the hilar and mediastinal lymph nodes (B, arrow) and multiple bones (C-E, arrows).

Figure 2 Sequence of anti-cancer treatments across the timeline and imaging evaluation of respective treatment. The primary tumor had a partial response to treatment with osimertinib. WBRT: Whole brain radiotherapy.

Figure 3 HE staining of specimens from two biopsies (baseline and re-biopsy before osimertinib). Squamous cell carcinoma was diagnosed by both pathological tests.

Figure 4 Pathological and gene alteration analyses of the two biopsies. Amplification refractory mutation system-polymerase chain reaction test only detected exon 19 deletion in both samples (A), whereas next-generation sequencing detected the presence of an EGFR T790M mutation in addition to the exon 19-deletion mutation (p.E746_A750del) of the re-biopsy sample (B). NGS: Next-generation sequencing; ARMS-PCR: Amplification refractory mutation system-polymerase chain reaction.