The ECOG PS (Eastern Cooperative Oncology Group Performance Scale) is a standard criteria for measuring how treatment of cancer impacts level of functioning in terms of the ability to care for oneself, daily activity, & physical ability (walking, working, etc.). Scale score ranges:0 to 5, 5 being the worst. Scale index: 0: Fully active, able to carry on all pre-disease performance without restriction. 1: Restricted in physically strenuous activity but ambulatory & able to carry out work of a light or sedentary nature. 2: Ambulatory & capable of all self-care but unable to carry out any work activities. Up & about more than 50% of waking hours. 3: Capable of only limited self-care, confined to bed or chair more than 50% of waking hours. 4 - Completely disabled. Cannot carry on any self-care. Totally confined to bed or chair. 5 - Dead. A deterioration of ECOG is an increase of 1 of the ECOG PS without improvement back to initial level at a subsequent time of measurement.