A case study involved that patient-derived non-small cell lung cancer organoids containing the rare EGFR 19Del/L643V double mutation type organoid, which was found to be responsive to osimertinib and gefitinib but resistant to erlotinib and icotinib, highlighting the importance of personalized treatment for patients harboring rare EGFR double mutations. The gene discussed is EGFR; the disease is non-small cell lung carcinoma.