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World J Clin Cases. Oct 26, 2026; 14(28): 127786
Published online Oct 26, 2026. doi: 10.12998/wjcc.127786
Published online Oct 26, 2026. doi: 10.12998/wjcc.127786
Primary renal carcinoid tumor in a horseshoe kidney presenting with constipation: A case report
Yi Zhao, Xing-Cheng Wu, Department of Urology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100730, China
Author contributions: Zhao Y wrote the article; Wu XC provided the case and performed the operation.
AI contribution statement: The authors take full responsibility and accountability for all content of this manuscript, including any portions for which AI tools were used as assistive technologies. All AI-assisted outputs were carefully reviewed, validated, and approved by the authors. AI tools were not used to generate original scientific data, perform independent scientific analyses, or draw scientific conclusions.
Supported by Peking Union Medical College Hospital Outstanding Young Talent Development Program, No. UBJ06536.
Informed consent statement: Written informed consent was obtained from the patient for publication of this case report and any accompanying images.
Conflict-of-interest statement: All authors declare that they have no conflict of interest to disclose.
CARE Checklist (2016) statement: The authors have read the CARE Checklist (2016), and the manuscript was prepared and revised according to the CARE Checklist (2016).
Corresponding author: Xing-Cheng Wu, MD, Department of Urology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, No. 1 Shuaifuyuan, Dongcheng District, Beijing 100730, China. wxc_pumch@163.com
Received: September 7, 2026
Revised: September 30, 2026
Accepted: October 22, 2026
Published online: October 26, 2026
Processing time: 46 Days and 22.6 Hours
Revised: September 30, 2026
Accepted: October 22, 2026
Published online: October 26, 2026
Processing time: 46 Days and 22.6 Hours
Core Tip
Core Tip: Primary renal carcinoid tumor (PRCT) is a rare neuroendocrine neoplasm strongly associated with a horseshoe kidney. This case describes a patient with refractory constipation as the main complaint. Clinicians should be aware of unexplained constipation in patients with a horseshoe kidney, even in the absence of hematuria or lumbago. Exclusion of extrarenal neuroendocrine origin and adequate postoperative oncologic surveillance are essential for PRCT management.