Long-Term Effect of Erlotinib Therapy in the Third Line of Anticancer Treatment in a Patient with Non-Small-Cell Lung Cancer - a Case Report.

BACKGROUND Malignant tumours of the trachea, the lungs, and the bronchus are the second most common type of tumour in the Czech Republic. Approximately three-quarters of cases are dia-gnosed in an advanced stage (IIIB-IV) and are one of the most common causes of death in all cancer groups. Targeted therapy brings a certain level of the improvement of prognostic outlook. In the Czech Republic, 1st and 2nd generation of tyrosine kinase inhibitors (gefitinib, erlotinib, afatinib) are indicated in the first-line anticancer treatment in non-small-cell lung cancer in locally advanced and metastatic stage, with proved activating mutation status of the epidermal growth factor receptor. Erlotinib is also indicated for use in the second or third line of anticancer treatment after a documented failure of previous chemotherapy. CASE A 70-year-old patient with lung adenocarcinoma, sensitive mutation in exon 19 of epidermal growth factor receptor gene, clinical-stage IV (according to the 7th edition of TNM classification), demonstrating long-term stable disease on erlotinib treatment after first-line gefitinib failure and second-line carboplatin-bevacizumab-paclitaxel combination chemotherapy failure. The disease treated with erlotinib has been stable for 48 months, although the dose has been reduced to 100mg per day due to side effects (rash). CONCLUSION While the efficacy of a gefitinib treatment in this case report was comparable to clinical trials results, the progression interval in this particular patient when treated with erlotinib is about 5 times longer compared to the progression observed in clinical trials. Another interesting fact is also a significant difference in the effect of these two tyrosine kinase inhibitors, which have shown comparable efficacy in clinical trials.