my father take tarceva on the first line treatment, and that time three brain tumors. after 15 month, the lund is stable, but the brain's tumor has been much larger than before, the number is much than before. he has headach and other symptoms. then, we began to pulsed tarceva 4 0 0 0. the sympotoms is relief. now, i need help, how long pulsed tarceva will working by your experience, and if i add 1 pill or 0.5 pill (150mg) on the third day or forth day, wether will accelarting the resistance of tarceva. hope Dr west will give me some advice. need your help. thanks a lot.