Living donor liver transplantation (LDLT) is regarded as a definitive but second-line treatment for patients with end-stage liver disease when deceased donors are unavailable. Donation from living donors has raised various ethical, psychosocial, and medical issues because donation requires sacrifice by living individuals. Autonomous consent to donation by adults is acceptable, but donation by minors has various ethical and psychosocial limitations. Kidney donation by minor family members has been rarely performed in Korea because renal replacement therapy allows most recipient candidates to wait for several years until the potential minor donors reach adulthood. By contrast, delay of donation for prolonged periods of time in LDLT candidates is often not feasible, as patient conditions often worsen rapidly, or hepatocellular carcinoma (HCC) progresses due to unfavorable treatment responses. Thus, some minors who may be the only suitable candidates for liver donation are willing to donate their liver to save the lives of closely related recipients. It is accepted that living liver donation by minors is regarded as justifiable only if minors possess the capacity to consent to donation and the procedure is in their best interests [1].

The present study analyzed the actual incidence of and reasons for LDLT by minor donors, as well as we discussed the ethical and psychosocial issues associated with liver donation by minors.

The study protocol was approved by the Institutional Review Board of the Asan Medical Center (AMC; IRB No. 2020-0856), which waived the requirement for informed consent due to the retrospective nature of this study. This study was performed in accordance with the ethical guidelines of the World Medical Association Declaration of Helsinki 2013.

During the 10-year period from 2010 to 2019, 4.1% and 7.5% of LDLT donors in the Korean nationwide KONOS and AMC databases, respectively, were minors. Although the proportions of minor donors have been gradually decreasing over time, they still constitute a considerable portion of living liver donors, primarily because further waiting would result in high waiting-list mortality rates and high drop-out rates from LDLT.

The body sizes of the minor donors aged 16–18 years were quite comparable to those of adults. Because minors with adult body dimension were intentionally chosen as LDLT donors, their incidence of postoperative complications was similar to that of young adult donors [2-4]. None of the 276 minor liver donors at AMC experienced major surgical complications, indicating that donor safety was not a major concern in the present study.

The main issues in the present study were the legal and moral framework regarding organ donation by minors. Minors are legally regarded as lacking the full capacity to make fully informed medical decisions. However, several studies suggest that minors aged >14 years demonstrate a level of cognitive maturity similar to that of adults, possessing adult‐like capacities for logical reasoning about moral, social, and interpersonal matters [5,6]. Although minors display cognitive capacities close to those of adults, they do not exhibit adult‐like levels of psychosocial maturity.

Four psychosocial factors are specifically relevant to decision‐making outcomes in minors [7-11]. The first is susceptibility to social coercion, in that minors have been shown to be more susceptible to coercive influences than adults [8]. The second factor is risk perception. In comparison with adults, minors place less weight on risk in relation to reward, and they often consider themselves invulnerable to harm [9]. The third is future orientation, or the extent to which an individual anticipates future consequences. Minors tend to focus mainly on the short‐term consequences of their choices, whereas adults also consider long‐term effects [10]. The fourth factor is impulsivity, in that minors are prone to more extreme mood swings, and have more difficulty in controlling their impulses and behavior [11]. The established cognitive maturity of minors suggests that they be regarded as having sufficient decisional capacity to make health care decisions that are generally not strongly influenced by any of the aforementioned psychosocial factors. By contrast, their psychosocial immaturity suggests that they be considered as lacking the decisional capacity to make health care decisions with a strong psychosocial component, including decisions that typically elicit impulsivity and involve high levels of social coercion or significant immediate risks/long‐term consequences [1].

To determine whether minors have the capacity to consent to living liver donation, it is necessary to identify the type of decision‐making process involved. Therefore, it is necessary to examine the extent to which each of the abovementioned psychosocial factors is relevant to the context of living liver donation by minors. As required by KONOS regulations, all minor donors in Korea are thoroughly assessed by psychiatrists and social workers who specialize in living donor organ transplantation.

The context of living organ donation exhibits certain features that increase the chances of coercive coercion. One such feature is that donation typically takes place between family members. In the case of living liver donation, there is the added element of the lack of any substitute therapy. Parents, regardless of whether they themselves or one of their children is in need of a liver, may pressure their minor child into donating. Minors are likely to succumb to such pressure because they are socially dependent on their parents. If the candidate recipient is a sibling, the latter may constitute an additional source of coercion [1]. The psychosocial factor of risk perception and future orientation is also highly relevant to the context of living liver donation by minors. Although the actual risks are very low [2-4], living liver donation is associated with some risks of mortality and morbidity. Although, impulsivity is not often a salient psychosocial feature of a minor's decision to consent to living liver donation, impulsivity may be a factor in exceptional circumstances. For example, a minor may be more impulsive if a parent suffers from acute liver failure and has a life expectancy of less than 1 week without transplantation [1]. Under such time pressure, a minor's impulses may dominate over deliberative, reasoned decision making [1]. Because of their psychosocial immaturity, minors considering living liver donation run the risk of yielding to coercive pressures, and placing too little weight on possible immediate and long‐term risks. However, a minor’s decisions under circumstances requiring expedited transplantation may not be rasher than considered, such that minors should not be regarded as completely incapable of consenting to living liver donation. Nevertheless, the possibility of donor risk indicates that, ideally, minors should not be considered potential living liver donors. However, as shown in the abovementioned example, saving a parent’s life through LDLT may be in the best interest of a potential minor donor. The peak of minor donation in AMC in 2012 was closely associated with a higher proportion of emergency LDLT, with a very low incidence of deceased donors. The peak in AMC in 2017 was associated with adoption of MELD score in KONOS liver allocation.

This study revealed that 92.8% of minor donors donated to first-degree family members, including parents and siblings. Because the candidate recipients had a very low chance of being allocated for DDLT in the current Korean setting with low incidence of deceased donors and MELD score-based liver allocation system, timely LDLT would be the only chance for prolonged survival. Considering the customs and emotions of most Korean families, there is a general consensus regarding the acceptability of minor donors, as it is directly related to their best interests.

Unexpectedly, we found that 7.2% of minor donors donated to second- and third-degree family members, including uncles, aunts, in-laws, and first cousins, and even to a grandmother. According to KONOS regulations and Korean law, minors are permitted to donate up to third-degree kinship. Because donation to these more distant relatives than first-degree kinship does not always appear to be in the best interest of minor donors, we believe it is reasonable to restrict minor donations only to first-degree family members. In early 2018, we recognized the ethical issues in KONOS regulations permitting minors to donate to second- and third-degree relatives; thereafter, our transplant program has not allowed minors to donate other than to first-degree family members, as well as reduced the incidence of donations by minors as much as possible. Thus, the annual number of liver donations by minors has markedly decreased, especially during the last 2 years. Recent increase in the incidence of deceased donors in Korea also helped to decrease the use of minor donors because the need for urgent LDLT was decreased [12,13].

This study had limitation of note, including its retrospective design, and inclusion of a single-center cohort. A Korea nation-wide collective study is needed to draw out consensus guidelines regarding donation by minors.

In conclusion, donation by minors is limitedly acceptable only when the procedure is the result of informed, well‐considered, and autonomous consent by the potential donor as well as being in the minor's best interests. We suggest that minors be allowed to donate only to first-degree family members, and not to the currently permitted second- and third-degree relatives. We think that our suggestion will make a compromise on transition toward not allowing donation by minors within the scope of current law.