Li QQ, Wei J, Fang LY, Zhou JL, Zhao HF. Primary ileal squamous cell carcinoma: A case report and review of literature. World J Clin Cases 2025; 13(36): 111835 [DOI: 10.12998/wjcc.v13.i36.111835]
Corresponding Author of This Article
Huan-Fen Zhao, Chief Physician, Professor, Department of Pathology, Hebei General Hospital, No. 348 Heping West Road, Shijiazhuang 050051, Hebei Province, China. hbghbinglike@126.com
Research Domain of This Article
Gastroenterology & Hepatology
Article-Type of This Article
Case Report
Open-Access Policy of This Article
This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
World J Clin Cases. Dec 26, 2025; 13(36): 111835 Published online Dec 26, 2025. doi: 10.12998/wjcc.v13.i36.111835
Primary ileal squamous cell carcinoma: A case report and review of literature
Qian-Qian Li, Jie Wei, Lu-Yao Fang, Jia-Lv Zhou, Huan-Fen Zhao
Qian-Qian Li, Lu-Yao Fang, Huan-Fen Zhao, Department of Pathology, Hebei General Hospital, Shijiazhuang 050051, Hebei Province, China
Jie Wei, Jia-Lv Zhou, Department of Pathology, Graduate School of North China University of Science and Technology, Tangshan 063210, Hebei Province, China
Author contributions: Li QQ and Wei J contributed to manuscript writing, editing, and data collection; Fang LY and Zhou JL contributed to data analysis; Zhao HF contributed to conceptualization and supervision. All authors read and approved the final version of the manuscript.
Informed consent statement: Informed written consent was obtained from the patient for publication of this report and any accompanying images.
Conflict-of-interest statement: All the authors report no relevant conflicts of interest for this article.
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).
Open Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Huan-Fen Zhao, Chief Physician, Professor, Department of Pathology, Hebei General Hospital, No. 348 Heping West Road, Shijiazhuang 050051, Hebei Province, China. hbghbinglike@126.com
Received: July 11, 2025 Revised: September 22, 2025 Accepted: December 15, 2025 Published online: December 26, 2025 Processing time: 168 Days and 4.9 Hours
Abstract
BACKGROUND
Primary ileal squamous cell carcinoma (PISCC) is a rare malignant tumor of the ileum. Its development is an exceptional phenomenon, as the ileal mucosa is lined exclusively by simple columnar epithelium, with no native squamous epithelium under physiological conditions. PISCC accounts for fewer than 0.001% of all intestinal malignancies. As of 2025, only 12 confirmed cases have been documented in the global literature, predominantly as isolated case reports.
CASE SUMMARY
A 47-year-old female developed abdominal pain two years after chemotherapy for ovarian low-grade serous carcinoma (International Federation of Gynecology and Obstetrics stage IC1). Positron emission tomography/computed tomography showed localized thickening of the small intestinal wall in the right pelvic region with increased metabolic activity, suggesting implantation metastasis. The patient underwent partial ileal resection, intestinal anastomosis, appendectomy, omentectomy, and pericolic lymphadenectomy. Histopathological and immunohistochemical analyses confirmed a primary ileal low-grade squamous cell carcinoma. Postoperatively, the patient received intravenous doxorubicin plus carboplatin combined with anti-angiogenic targeted therapy. After six cycles, the regimen was changed to paclitaxel plus carboplatin with bevacizumab. Following five cycles, maintenance therapy with intravenous bevacizumab monotherapy was initiated, supplemented with adjunctive hepatoprotective agents. At the 30-month postoperative follow-up, the patient remained progression-free with no clinical or radiologic evidence of recurrence or distant metastasis.
CONCLUSION
Accurate diagnosis of PISCC requires integration of clinical history, systemic examination, histopathology, and immunohistochemical profiling to reduce misdiagnosis and missed diagnosis.
Core Tip: Primary ileal squamous cell carcinoma represents a paradox, as it arises in the ileal mucosa that lacks native squamous epithelium. With an incidence of less than 0.001% among intestinal malignancies and only 12 confirmed cases worldwide (as of 2025), this rare entity remains poorly characterized in the literature. Here, we report a newly diagnosed case of primary ileal squamous cell carcinoma and synthesize its clinicopathologic features, clinical presentation, therapeutic management, and the patient’s outcome and prognosis, with particular emphasis on diagnostic dilemmas and treatment efficacy.
