{Reference Type}: Case Reports {Title}: EGFR-TKI-induced Factor V deficiency in a patient with advanced non-small cell lung cancer: The first case report. {Author}: Yoshizaki C;Yoshida Y;Nohmi S;Go Y;Kusakado R;Kawamura S;Inoue D;Kabasawa N;Yamaguchi F; {Journal}: Lung Cancer {Volume}: 194 {Issue}: 0 {Year}: 2024 Aug 1 {Factor}: 6.081 {DOI}: 10.1016/j.lungcan.2024.107869 {Abstract}: Osimertinib, a third-generation epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI), is routinely prescribed as first-line therapy for advanced non-small cell lung cancer, regardless of the presence of the T790M resistance mutation. This study reports a rare case of Factor V inhibitor detection during osimertinib therapy in a patient with lung adenocarcinoma. These findings underscore the importance of vigilant monitoring for coagulation abnormalities during EGFR-TKI therapy.