The main purpose of this study of pemetrexed combined with cisplatin used as neoadjuvant
chemotherapy (2 or 3 cycles) in participants with operable non-small cell lung cancer (NSCLC)
is to look at various genes present in participants' blood and tumor tissue to see if there
is any link between the levels or changes in the genes and how participants with lung cancer
respond to pemetrexed and cisplatin treatment.