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We are grateful for the thoughtful and constructive observations offered by Drs Afzal and Nisa [1] concerning our recent publication [2]. As they rightly underscore, surveillance bias and the age profile of the cohort are pivotal to interpreting the reported incidence of malignancy, especially in living kidney donors (LKDs). First, with respect to surveillance bias, we have already acknowledged that it cannot be fully eliminated given our observational cohort design. Indeed, many of the malignancies identified in this study were detected not because of symptoms or incidental findings but through active surveillance undertaken at our institution, as detailed in tab. 2 [2]. This surveillance included chest and abdominal CT, abdominal ultrasound, and upper and lower gastrointestinal endoscopy, and it frequently facilitated early diagnosis and curative treatment. Moreover, given that LKDs are reported to have relatively high health literacy [3], their proactive health-seeking behaviour may have contributed to higher detection rates and thereby accentuated surveillance bias. Therefore, consistent with the position articulated by Engels et al., we do not consider it appropriate—based on our data—to make any claim as to whether kidney donation per se increases the risk of malignancy [4]. We have stated this explicitly in the Conclusion of our manuscript. Second, with respect to age, it is well established in the general population that older age is the most significant risk factor for malignancy, and our findings are consistent with this. LKDs who developed malignancies were significantly older at the time of donation than those who did not (64.8 ± 6.1 years vs. 60.1 ± 8.8 years; p = 0.02) [2]. We believe the observed incidence reflects the combined influence of older age at donation and aging during the long-term follow-up period. At present, particularly for younger donors, whether active surveillance should be undertaken remains uncertain. While age-appropriate, guideline-recommended population screening ought to be mandatory, any additional active surveillance should be individualised under the principle of ‘do no harm’. Decisions should be made on a case-by-case basis, weighing classical risk factors (e.g., family history, prior colorectal polyps and smoking history) and the specific characteristics of LKDs. In conclusion, the aim of this study is not to claim that ‘LKDs have a higher risk of malignancy’, but to highlight the importance of long-term and systematic surveillance. We believe that combining public health screenings with active surveillance enables early detection of malignancies and supports sustained health maintenance, thereby ensuring the safety of LKDs. Protecting the health of LKDs is essential not only from the standpoint of Evidence-Based Medicine but also from the perspective of ‘Enduring-care Based Medicine’, which emphasises long-term, respectful and supportive care with a particular focus on protecting living organ donors. The authors have nothing to report. All procedures involving human participants were performed following the ethical standards of the institutional and/or national research committee of the participating institutions and were performed per the 1964 Helsinki Declaration and its later amendments or comparable ethical standards. The reported clinical and research activities were consistent with the Principles of the Declaration of Istanbul, as outlined in the Declaration of Istanbul on Organ Trafficking and Transplant Tourism. All procedures in this study were performed per the ethical standards of the Institutional Research Committee of the St. Marianna University School of Medicine (IRB No. 6137). This was a retrospective observational study without new interventions or invasive procedures and was performed according to the Ethical Guidelines for Medical and Health Research Involving Human Subjects established by the Ministry of Health, Labor, and Welfare (Japan) and the Institutional Review Board of the St. Marianna University School of Medicine. The requirement for written informed consent was waived for all participants. An opt-out method was used to obtain consent for this study. The authors declare no conflicts of interest. All clinical data were available from the electronic medical records at St. Marianna University Hospital. The data supporting the findings of this study are available from the corresponding author upon reasonable request.