Recent advancements in targeted therapies for non-small-cell lung cancer (NSCLC), specifically focusing on epidermal growth factor receptor (EGFR) mutations, have revolutionized treatment strategies. Osimertinib, an approved therapy for metastatic NSCLC with EGFR mutations, highlights remarkable efficacy but also harbors the potential for severe adverse events, whose rarity or lack of precedence may mask their criticality. This article delves into the exploration of adverse events linked to osimertinib, shedding light on a rare yet life-threatening occurrence: severe myelosuppression. A case study detailing a patient with EGFR-mutated NSCLC exhibiting a robust treatment response but experiencing severe myelosuppression following osimertinib initiation is presented. Immediate discontinuation of osimertinib alongside concurrent blood transfusions facilitated toxicity recovery, prompting a successful reduction in myelosuppression severity upon re-administration at a lowered dosage.
