This dissertation represents an exploration of the ways that people diagnosed with a malignancy conceptualize cancer. Discovering attitudes and tacitly held beliefs about cancer can help to generate a vocabulary for more effective interchange in doctor-patient discourse, amend the presentation of clinical recommendations to reflect an understanding of patient disease models, and thus bridge the disparate clinical realities of patient and physician or other professional provider. To gather data revealing the perspective of cancer patients this investigation utilized a qualitative methodology, specifically Transcendental Phenomenology. In-depth individual interviews were conducted with 20 adults, all of whom within the recent year had received an initial diagnosis of cancer. In accordance with phenomenological principles, these interviews were carried out using a semi-structured interview format and were undertaken in a conversational style. This approach helped to facilitate extensive, personal, and relatively uncensored responses from each participant. Through a systematic analysis of data the following five textural themes emerged: (1) Undetected Enemy Takeover; (2) Ultimate Uncertainty and Vulnerability; (3) Inevitable or Imminent Death; (4) Assumptive World Fracture; and (5) Personal Disease Saga. These shared perceptual themes are structured by a set of seven underlying conditions, understood in phenomenological research as fundamental relationship-to-world organizing principles: temporality, spatiality, bodyhood, materiality, causality, relationship to others, and relationship to self. In effect, these seven structures are the dynamic underpinnings that precipitate and account for the specifics of the phenomenon of interest, the perceptual experience of cancer.