Introduction: Breast cancer remains a major public health concern, with timely access to diagnosis and treatment shaped by territorial, social, economic, organizational, and relational factors. Although regulatory frameworks establish timeframes for diagnosis and treatment within the Brazilian Unified Health System (SUS), time and service-delivery indicators do not fully capture women’s lived experiences throughout their therapeutic itineraries. Objective: To understand how women with breast cancer experience and make sense of their therapeutic itineraries, from the perception of bodily changes through diagnosis and treatment, considering access barriers, travel, relationships, and experiences of care, as well as their implications for autonomy, dignity, vulnerability, and justice from a bioethical perspective. Methods: This qualitative, descriptive, and interpretive study was conducted at a High-Complexity Oncology Care Center in Rio Grande do Norte, Brazil. Participants were 16 women with histopathologically confirmed breast cancer who received care through the SUS. Data were generated through semi-structured interviews conducted between March and June 2026 and analyzed using Braun and Clarke’s reflexive thematic analysis, complemented by lexical analysis. Interpretation was informed by the access model developed by Levesque, Harris, and Russell and by bioethical frameworks, including principlism, the Bioethics of Protection, and the Universal Declaration on Bioethics and Human Rights. Results: The mean age of participants was 59.4 years; 87.5% self-identified as mixed-race (parda), and 81.3% as Catholic. Breast self-examination was the main means of detecting breast abnormalities (81.3%). The mean interval between symptom onset and diagnosis was 4.2 months, increasing to 5.5 months among participants whose entry point into care was the SUS. The mean interval between diagnosis and initiation of treatment was approximately one month. Thematic analysis identified four themes: discovery and perception of the body; access barriers, geography, and transportation; therapeutic itineraries mediated by relationships, welcoming care, and support networks; and the emotional and spiritual dimensions of the experience. The narratives revealed difficulties related to delays in investigation, access to diagnostic tests, travel, and the recognition and valuation of women’s complaints, while also highlighting the welcoming attitudes of healthcare professionals, family support, and relationships developed throughout the care process. Conclusion: Therapeutic itineraries are shaped by the interaction between structural barriers and relational resources mobilized by women. Although the interval between diagnosis and treatment was relatively shorter, barriers prior to diagnostic confirmation persisted, revealing situations of vulnerability in which the exercise of the right to healthcare depends on financial and relational resources, as well as on women’s individual persistence.