A gentleman in his sixties presented with chest pain and pain in the left hip. An X-ray of the chest showed a left lung mass. A whole body PET CT confirmed a left lung mass with lesions in the left iliac bone and vertebrae which were compatible with metastatic lesions. A CT guided biopsy from the lung confirmed adenocarcinoma. Molecular studies showed a mutation in exon 19 of the Epidermal Growth Factor (EGFR) gene. Magnetic Resonnance Imaging (MRI) of the brain was normal

Patient received Radiation to the left iliac bone for pain relief. He was started on Tablet Geftinib 250 mg (a drug which acts on EGFR pathway) once daily along with Pemetrexed and Carboplatin chemotherapy. After 4 cycles of chemotherapy patient had significant improvement of symptoms and shrinking of the cancer on PET Scan. Inj Pemetrexed and Tab Geftinib were continued.

After nearly 16 months of treatment patient had increase in the size of the lung mass. A repeat biopsy showed the appearance of a new mutation T790M. The patient was started on a targeted drug osimertinib which is specific for this mutation. He continues this treatment for nearly one year and has good control of disease.

Message: Molecular testing is an important tool in the evaluation of patients with lung cancer and helps to choose appropriate therapy.