Beyond Standard Care: Japan's Supreme Court on Doctor's Duty to Explain Unestablished Treatment Options

Decision Date: November 27, 2001, Supreme Court of Japan, Third Petty Bench (Heisei 10 (O) No. 576)

In a landmark judgment on November 27, 2001, the Supreme Court of Japan clarified a physician's duty to inform patients about alternative medical treatments, even those not yet considered fully established medical practice. The case involved a breast cancer patient who argued her doctor failed to adequately explain breast-conserving therapy (BCT) as an option before performing a mastectomy. This ruling significantly impacted the understanding of informed consent and patient autonomy in Japan, particularly concerning treatments with profound quality-of-life implications.

The Patient's Diagnosis and Doctor's Initial Plan

In January 1991, the plaintiff, X, sought consultation from Dr. Y, a practicing physician whose clinic in Izumisano City, Osaka Prefecture, included a special outpatient service for breast diseases and performed breast cancer surgeries. By February 14, 1991, X was diagnosed with breast cancer. Dr. Y determined that a modified radical mastectomy (a procedure that removes the entire breast but preserves the chest muscles) was the appropriate treatment for X's condition.

On February 16, 1991, Dr. Y informed X of the need for inpatient surgery. He mentioned that methods to preserve the breast (breast-conserving therapy or BCT) were also practiced, but cautioned that this approach could result in skin discoloration due to radiation therapy or might necessitate re-surgery. On February 20, Dr. Y further explained to X that her entire breast would be removed, though the underlying muscles would be spared.

The Patient's Expressed Interest in Breast Conservation

Concurrently, on February 15, 1991, X had come across a newspaper article that discussed breast cancer treatment moving towards breast preservation and mentioned BCT favorably. When X was admitted to Dr. Y's clinic on February 26, 1991, she handed him a letter. Although this letter is no longer extant, it reportedly expressed the profound emotional conflict she experienced as a woman diagnosed with breast cancer, caught between the desire for survival and the prospect of losing her breast. Dr. Y understood from this letter that X had a strong interest in the possibility and applicability of BCT for her specific condition. Despite this, on February 28, 1991, Dr. Y proceeded to perform the mastectomy on X.

The Status of Breast-Conserving Therapy (BCT) in Japan (Early 1990s)

At the time of X's surgery in early 1991:

• In Western countries, BCT was increasingly recognized, with some studies suggesting its outcomes regarding cancer recurrence and patient survival were comparable or even superior to mastectomy.
• In Japan, however, the adoption of BCT was relatively slow, and mastectomy remained the mainstream treatment for breast cancer.
• Nevertheless, BCT was not unknown in Japan. Dr. Y himself had prior experience performing BCT in one instance (though without subsequent radiation therapy).
• Dr. Y was aware that BCT was being performed by a "not insignificant number" of medical institutions in Japan, that there was a "considerable number" of cases, and that it was receiving "positive evaluation" among physicians who performed it. A survey by a breast cancer research group (of which Y's clinic was a member) later showed that BCT accounted for 6.5% of breast cancer surgeries in member facilities in fiscal 1989, 10.2% in 1990, and 12.7% in 1991. Another survey indicated 129 facilities nationwide performed BCT in 1991, including several in Osaka Prefecture.
• Dr. Y also knew that X's specific type of breast cancer was potentially suitable for BCT, meeting the criteria of a prominent research group (the "Kasumi-han," a Ministry of Health-supported study group on BCT) which had provisionally established BCT implementation guidelines in October 1989. He was also aware of medical institutions that were performing BCT.

The Doctor's Actions and The Lawsuit

X subsequently sued Dr. Y for approximately 11.91 million yen in damages. She argued that her cancer was suitable for BCT, a treatment she desired, but Dr. Y performed the mastectomy against her wishes and without providing sufficient explanation about BCT, thereby violating her right to make an informed choice.

Lower Court Rulings

The Osaka District Court, in its first instance judgment, found that Dr. Y had breached his duty of explanation (a default under the medical services contract) and awarded X 2.5 million yen in damages. However, the Osaka High Court reversed this decision. The High Court acknowledged that the efficacy and safety of BCT were gaining recognition at the time but reasoned that its implementation rate was still low and its safety not yet definitively established in Japan. Therefore, it concluded that Dr. Y was not in a position where he was obligated to specifically ask X if she wished to consider BCT, and thus found no breach of his explanation duty. X appealed this ruling to the Supreme Court.

The Supreme Court's Landmark Decision (November 27, 2001)

The Supreme Court overturned the Osaka High Court's decision and remanded the case for further proceedings. The Court laid out a nuanced framework for a physician's duty to explain alternative treatments, especially those not yet fully established:

• General Duty of Explanation: The Court reaffirmed the basic principle that a physician, when performing surgery, has a duty under the medical services contract (unless special circumstances exist) to explain to the patient the diagnosis (name and condition of the disease), the nature of the planned surgery, associated risks, any other available treatment options with their respective advantages and disadvantages, and the prognosis.
• Explaining Unestablished Alternatives: The central issue was whether Dr. Y had a duty to explain BCT, which was considered an unestablished therapy in Japan at that time, as an alternative to the established procedure of mastectomy.
  • The Court stated that a physician does not always have a duty to explain an alternative therapy if the planned procedure is an established medical standard and the alternative is not.
  • Conditions Triggering the Duty for Unestablished Therapies: However, such a duty can arise even for an unestablished therapy if certain conditions are met. Specifically, the duty exists if:
    1. The unestablished therapy is being performed by a "not insignificant number" of medical institutions.
    2. There is a "considerable number of実施例" (cases performed).
    3. It has received "positive evaluation" among the physicians who have performed it.
    4. The patient may be a candidate for this therapy.
    5. The physician is aware that the patient has a "strong interest" in whether the therapy is applicable to them and feasible.
  • Scope of Explanation Required: If these conditions are met, the physician—even if they personally hold a negative view of the unestablished therapy or do not intend to perform it themselves—still has a duty to explain to the patient, to the extent of their knowledge:
    • The nature and content of the unestablished therapy.
    • Its potential applicability to the patient's condition.
    • The potential benefits and drawbacks (利害得失 - rigai tokushitsu) if the patient undergoes it.
    • The names and locations of medical institutions where the therapy is being performed.
• Heightened Duty for Breast Cancer Surgery: The Supreme Court emphasized that the imperative to explain BCT as a possible alternative to mastectomy is stronger than for many other types of surgery. This is because breast cancer surgery involves an organ symbolic of femininity and located on the body's surface; its loss can cause not only physical disability but also significant psychological and emotional effects due to changes in appearance, deeply impacting the patient's "quality of life" (生活の質 - seikatsu no shitsu) and "fundamental way of living or outlook on life" (患者自身の生き方や人生の根幹 - kanja jishin no ikikata ya jinsei no konkan).
• Application to Dr. Y: Dr. Y was a specialist in breast cancer affiliated with a research group, had personal (though limited) experience with BCT, and was aware of its increasing practice, positive evaluations by other doctors, X's potential suitability for the procedure, and institutions that offered it. X's letter, expressing her deep distress and desire to preserve her breast, clearly communicated her "strong interest" in BCT to Dr. Y.
• Dr. Y's Duty to X: The Court concluded that once Dr. Y received X's letter, he incurred a duty to clearly explain to her, based on his knowledge, her potential eligibility for BCT and the names and locations of institutions offering it. This was necessary to provide X with a genuine opportunity to deliberate and decide whether to proceed with a mastectomy performed by Dr. Y or to explore the possibility of BCT at another medical facility. The Court clarified that this duty did not obligate Dr. Y to perform BCT himself if he believed mastectomy was the most appropriate treatment for X, nor did it require him to actively recommend BCT.
• Insufficiency of Prior Explanation: Dr. Y's earlier, brief, and somewhat negative explanation of BCT (on February 16) was deemed insufficient to meet this heightened duty of explanation that arose after he received X's letter indicating her strong interest.

The Supreme Court found that the Osaka High Court had erred in its interpretation of the physician's explanation duty and remanded the case for reconsideration based on these principles. (Following the remand, the Osaka High Court, on September 26, 2002, found in favor of X, awarding her 1 million yen for emotional distress and 200,000 yen for attorney's fees due to Dr. Y's breach of his explanation duty).

Analysis and Significance

This Supreme Court decision was a landmark in the field of medical law and informed consent in Japan:

• First Supreme Court Ruling on Explaining Unestablished Alternatives: It was the first time Japan's highest court directly tackled a physician's duty to explain an alternative therapy that was not yet considered an established medical standard, particularly when the proposed primary treatment was itself an established one. This had a considerable impact on medical practice and the evolving understanding of patient rights.
• Moving Beyond "Medical Standard" as the Sole Criterion: Previous Supreme Court precedents, such as a case concerning retinopathy of prematurity, had more rigidly tied a physician's explanation obligations to what was deemed the "medical standard" at the time of treatment. This 2001 ruling marked a significant development by incorporating other factors, such as the availability and emerging status of alternative treatments and, crucially, the patient's expressed strong interest in those alternatives, even if they were not yet fully "established". One commentator noted that this decision "leads the medical standard theory to a new stage".
• Patient's "Strong Interest" as a Decisive Factor: The patient X's letter to Dr. Y played a pivotal role in the Court's decision. The act of handing this letter, which conveyed her deep concerns about breast loss, was recognized as a clear demonstration of her strong interest in BCT, thereby triggering Dr. Y's heightened duty of explanation.
• "Quality of Life" and Patient Self-Determination: The ruling's explicit consideration of the patient's postoperative "quality of life" as a key factor, especially in the context of breast cancer surgery, strongly links the physician's explanation duty to the patient's right to self-determination. This empowers patients to make informed choices about treatments that align not only with medical indications but also with their personal values, life plans, and overall well-being.
• The Scope of Self-Determination: The legal commentary provided with the case highlights that this emphasis on self-determination raises further questions, such as the extent to which a patient can demand a specific treatment (especially an unestablished one) that a physician may not endorse, or conversely, refuse standard, potentially life-saving treatments (e.g., blood transfusions for religious reasons). There is a noted concern about the potential negative consequences of an overemphasis on self-determination if it inadvertently leads to patients shouldering undue risks without fully grasping all implications.
• Case-by-Case Assessment: The commentary also cautions that while this judgment provides important principles, establishing a universal, one-size-fits-all standard for when physicians must explain unestablished therapies remains challenging. Each case requires careful consideration of its specific facts and circumstances. Attempting to rigidly generalize the conditions outlined in this ruling (such as what constitutes a "not insignificant number" of institutions or "positive evaluation" among doctors) could present practical difficulties and encroach upon physicians' professional judgment and discretion, especially when expert opinions on an emerging therapy might be divided.

Concluding Thoughts

The Supreme Court's 2001 decision significantly advanced the principles of patient autonomy and informed consent in Japan. It established that physicians have a nuanced duty to inform patients not only about standard treatments but also, under specific conditions, about emerging or unestablished alternatives, particularly when these alternatives have profound implications for the patient's quality of life and the patient has expressed a strong interest. This case underscores the critical importance of thorough communication and respecting a patient's right to make deeply personal medical choices based on comprehensive information, even if that information extends beyond the physician's preferred or routinely offered treatments.