Extraordinary response to erlotinib therapy in a patient with lung adenocarcinoma exhibiting KRAS mutation and EGFR amplification.

Case reports on the co-incidence of Kirsten rat sarcoma (KRAS) mutation and epidermal growth factor receptor (EGFR) amplification in patients with NSCLC are very rare. This combination is usually considered a negative prognostic factor, despite EGFR amplification alone having positive predictive value. The whole course of treatment of a patient with both EGFR amplification and KRAS mutation present is decribed. The patient in question was a smoker for whom both first- and second-line chemotherapy had been unsuccessful. In stage IV disease biological therapy was administered and proved highly beneficial. Today, 38 months since commencing the treatment, the patient still has no signs of progression and the therapy is still in progress.