Rare tumors, rare dilemmas: When evidence runs out, ethics begins

When talking about cancer care, we often assume that clinical decisions are guided by strong evidence and clear guidelines. But for patients with rare tumors, this assumption falls apart, as data is limited, recommendations often conflict with one another and patients are asked to make difficult decisions in the face of uncertainty.

This uncertainty is the focus of our recent paper, “Rare tumors, rare dilemmas: ethical considerations for a clinician-researcher.” In this discussion, we explore what happens when clinicians must care for patients while simultaneously generate the very evidence that guides care – an unfortunate but common reality in the management of rare diseases.

Rare tumors present a unique ethical challenge. Because cases are uncommon, management often relies on small case series, expert opinions or institutional experience rather than large-scale randomized trials. As a result, a clinician may have to serve as both caregiver and researcher, and while this overlap can drive innovation, it also introduces ethical tensions.

One key issue is implicit bias and allegiance bias, in which a provider’s background or research findings may subtly influence clinical recommendations and decision-making. In rare cancers, where only a handful of experts may exist, patients may hear recommendations as definitive even when evidence is conflicting or limited. Without careful communication, uncertainty can be unintentionally minimized, and these challenges are especially apparent when considering aggressive interventions, such as extensive staging procedures or treatments with significant morbidity. As a result, patients are often navigating these difficult choices while being newly diagnosed, overwhelmed and unsure how much uncertainty exists behind the recommendations.

This is where ethics becomes essential to practice, not just as an abstract concept but also as a clinical skill. Ethical care in rare diseases requires transparency about uncertainty, humility about the unknown and efforts to distinguish between evidence and expert opinion. It also requires recognizing that informed consent is not a single conversation but an ongoing process that evolves as values become clearer.

Importantly, our work does not argue against clinician-led research and innovation, as progress in rare diseases depends on clinician-researchers. Instead, we advocate for an ethical framework for effective counseling that includes the following:

• Summarize the current evidence in simple terms without statistical jargon.
• Discuss procedural risks against possible, but unproven, benefits in prognostic clarity.
• Acknowledge and disclose potential conflict of interest.
• Explore patient values regarding information versus intervention.
• Consider a multidisciplinary review (e.g., tumor board, surgical oncologists, radiation oncologists, surgeons) to integrate diverse expertise and reduce individual bias.
• Collaboratively decide on management, documenting the discussion to enhance clarity.

Importantly, rare tumors offer a reminder that medicine is not always about finding the perfect answer. Sometimes, it is about guiding patients honestly through situations where no clear answer exists. As the management of rare disease care progresses, these ethical dilemmas will likely become more common. Recognizing and addressing these issues is essential to ensuring that progress remains aligned with patient trust and values.

By Minh B. Nguyen, third-year medical student, and Dr. Tejas Prasad Joshi, medical resident, Baylor College of Medicine