Samples will be collected before the systemic therapy. After initiation of therapy, samples will be collected at end of the 1st month, at the end of the 2nd month at the end of 3rd months and once every three months thereafter concurrently with the tumor assessment such as time of performing CT scans. In selected consented patients, peripheral blood samples will be collected every week for the first month.
Disease status will be assessed every 2\~3 months and at the end of treatment according to RECIST criteria. If progression is not observed at the end of therapy, patients will be assessed every 3 months until progression or further anti-cancer therapy. Progression-free survival, overall survival and response rate will be reported.
