Table 2. EGFR TKIs patients received.

Record #	EGFR TKIs received before SCLC transformation	Rechallenge/continuation	EGFR TKIs received after SCLC transformation
1	Gefitinib → Erlotinib	Continuation	Erlotinib → Osimertinib
2	Afatinib	Continuation	Afatinib
3	Erlotinib → Osimertinib	Rechallenge	Erlotinib
4	Osimertinib	N/A	N/A
5	Erlotinib → Osimertinib	Continuation	Osimertinib
6	Afatinib	Rechallenge	Osimertinib
7	Erlotinib → Osimertinib	Continuation	Osimertinib
8	Erlotinib	N/A	N/A
9	Erlotinib	N/A	N/A

EGFR TKIs that each patient received before and after SCLC transformation. Four patients’ transformation occurred with respect to Osimertinib, and three of them received sequential treatment with 1st generation to 3rd generation of TKIs. EGFR, epidermal growth factor receptor; SCLC, small cell lung cancer; TKIs, tyrosine kinase inhibitors; N/A, not applicable.