Clinical Decision Support Across Oncology and Reproductive Medicine in Oncofertility Care

Sir, Shimizu’s recent review, Pregnancy after breast cancer: Development of an oncofertility program in Japan, demonstrates that the critical intervention in oncofertility care is not fertility preservation itself but the management of the boundary between oncology and reproductive medicine.[1] This letter argues that decision support across this boundary should be treated as a core component of oncofertility care, rather than as an incidental consequence of program infrastructure.[1,2] WHAT THE ARTICLE ADVANCES The article’s primary contribution is its clear delineation of Japan’s two-institution oncofertility model. Shimizu describes a structured care pathway linking a cancer center with a reproductive medicine center, in which oncology nurses identify fertility concerns early, consolidate treatment information, coordinate referrals, and provide psychosocial support during transitions between services.[1] She contrasts this with a regional network model used where reproductive expertise is less readily available, relying on centralized counseling and interinstitutional coordination.[1] Across both approaches, the same conclusion emerges: access to fertility preservation depends not only on service availability but also on defined pathways that enable patients to cross institutional boundaries in a timely manner, with clinically and emotionally sufficient support.[1] SHARED CHALLENGES ACROSS NATIONAL CONTEXTS This insight is relevant beyond Japan. Yufe et al. found that supportive care for young women with breast cancer often remains divided between hospital-based programs, which tend to offer structured, empirically supported interventions, and community-based organizations, which more commonly provide informal social and practical support.[2] Although hybrid models that combine hospital and community resources were identified as the most comprehensive approach, such integration was uncommon.[2] Read alongside Shimizu’s analysis, this suggests that the central challenge is not whether integrated, multidisciplinary models exist, but whether they function as routine care when time-sensitive fertility decisions must be made. Even in health systems where comprehensive programs have been developed (most often in large academic centers), these models remain the exception rather than the prevailing configuration of care.[1,2] GAPS THAT TRANSCEND HEALTH SYSTEMS Shimizu underscores why balancing cancer control with reproductive goals is especially challenging for younger patients who wish to conceive.[1] Much of the evidence guiding oncofertility care remains conditional; however, the POSITIVE trial provides the strongest prospective data to date, suggesting that temporarily interrupting adjuvant endocrine therapy to attempt pregnancy was not associated with a higher rate of breast cancer events during the reported 5-year follow-up among premenopausal women with prior hormone receptor–positive early breast cancer.[3] However, findings are constrained to trial participants and have limited applicability to other breast cancer subtypes. Even among POSITIVE-like patients, interruption and resumption of endocrine therapy may be more variable and less structured. Indeed, real-world data showing low rates of endocrine therapy resumption after pregnancy point to another gap: decision support itself.[4] Without structured support across transitions between oncology, reproductive medicine, and long-term follow-up, all young patients with breast cancer may 1 day gain access to fertility preservation yet still carry the primary burden of uncertainty. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest. Data availability statement Further details of data referred to and discussed in the manuscript are available from the corresponding author upon request.