For individuals facing cancer, the battle is a personal one, and whether one lives or dies, the experience is always traumatic. Mary Elizabeth Williams, a staff writer for Salon, has been sharing her own cancer story on the website over the past several months. Last month, after undergoing experimental trials for her metastatic Stage 4 cancer, her doctor told her that her tumors had disappeared.   Mary Elizabeth is what the cancer community refers to as a survivor. But in her opinion, survivor does not quite define what she and many others feel like after treatment.