Therapy-related myeloid leukemia during erlotinib treatment in a non-small cell lung cancer patient: A case report

BACKGROUND Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) are tolerable drugs used for patients with EGFR-mutant advanced non-small cell lung cancer (NSCLC). Serious adverse reactions are uncommon compared with cytotoxic drugs. CASE SUMMARY A 52-year-old man presented with general weakness and cytopenia. He had been taking erlotinib for 11 mo to treat NSCLC. The pathological diagnosis from the right upper lobe mass was adenocarcinoma with an EGFR mutation in exon 21 (L858R). He had previously received paclitaxel/carboplatin, gemcitabin/ vinorelbine chemotherapy, stereotactic radiosurgery for brain metastasis, and whole-brain radiotherapy as treatment for NSCLC. We diagnosed the patient with acute myeloid leukemia (AML). During the induction and consolidation chemotherapy for AML, the erlotinib was discontinued. When complete remission of the AML was achieved, since the lung masses were increased, pemetrexed/ cisplatin for the NSCLC was initiated. After two cycles of chemotherapy, the cytopenia was prolonged. AML relapse occurred with the same karyotype. CONCLUSION Therapy-related acute myeloid neoplasm (t-MN) is a rare but fatal late complication. Although a patient may be taking EGFR-TKIs, the possibility of t-MN should be considered. Further studies are needed to determine whether EGFR-TKI usage is a predisposing factor for t-MN.