This dissertation explores how language has evolved as metastatic breast cancer (MBC) has shifted from an imminent death sentence to a potentially chronic disease. War rhetoric, of which the survivor trope is a part, has been the primary mechanism by which healthcare defines the cancer experience. Using Celeste Condit's framework of rhetorical formations, I question if a new rhetoric of breast cancer is indeed emerging as new developments in medicine allow women with terminal disease to live longer. My data reveals that this new rhetorical formation, of which metavivor rhetoric is the anchor point, contains its own key metaphors and rhetorical appeals. In metavivor rhetoric, the focus becomes living with cancer, in which simply existing through a sense of homeostasis develops as the central part of the rhetoric. In this homeostasis as the key part of metavivor rhetoric, a cure is not the focus, as it is in survivor rhetoric. I explore how this emerging rhetoric supersedes the war rhetoric that is deeply entrenched in medical discourse--especially breast cancer--for decades, and how metavivor rhetoric builds upon and repudiates the war rhetoric. Through my qualitative rhetorical analysis of a popular breast cancer message board for patients with metastatic disease, I coded 589 posts to see how women use language to discuss living with MBC, and Condit's concept of rhetorical formations allows me to argue more specifically for the changes I see in patient discourse. My analysis revealed that women living with MBC argue against war/survivor rhetoric and prefer metavivor rhetoric and its ancillary terms, allowing them to transition to an acceptance of their own mortality. I conclude that a new rhetorical formation has taken shape within MBC patient discourse, with implications for women's mortality as they live with a chronic disease, and as I look to the future of this research, my goal is to promote rhetorical changes that will help to enfranchise women with MBC into the broader breast cancer discourse in the United States. / Doctor of Philosophy / Metastatic breast cancer has become a disease that some women can live with for many years, as treatments have advanced for this specific type of cancer. As this disease has become a chronic condition for many women, the language that women use to discuss living with chronic cancer has also shifted. Using the framework of Celeste Condit's rhetorical formations, which encompasses uses of metaphors, topics, and values, among other rhetorical features, I examine how language has shifted from one of war and survivor rhetoric to that of metavivor rhetoric. In metavivor rhetoric, the focus becomes living with cancer, through a sense of homeostasis and of simply existing with cancer. Within homeostasis as the key part of metavivor rhetoric, a cure is not the focus, as it is in survivor rhetoric. By examining how women talk about living with cancer on a popular online breast cancer support group, I analyze the shifts that take place in their language and argue that women have moved from the dominant war and survivor rhetorical formation to one that is grounded in metavivor rhetoric and the idea of homeostasis. Within this evolution comes a transition to their own mortality as they come to better understand what it means to live with a chronic, yet ultimately, terminal, illness and an acknowledgment of the impact that their lives' perceived time has on these language choices.