Analysis of misdiagnosis causes of colorectal adenocarcinoma as colorectal polyps

HUANG Huiwen; WANG Jinqiong; LI Xiaoyu; WANG Yilin; OUYANG Yongwen; LU Qinghua

doi:10.3969/j.issn.1002-3429.2026.06.002

Abstract：Objective To investigate the misdiagnosis causes of colorectal adenocarcinoma as benign polypoid lesions.Methods A retrospective analysis was conducted on the clinical data of 33 patients with misdiagnosed colorectal adenocarcinoma who were admitted from December 2023 to March 2025.Results Among the 33 patients,27(81.81%)were identified through asymptomatic screening.There were 2 cases(6.06%)of simple hematochezia and 4 cases(12.12%)with accompanying abdominal pain.For all of them,the initial diagnoses was colon polyps based on endoscopic examination.Of them,29 patients underwent endoscopic resection of the lesion,and 4 patients received surgical treatment.Postoperative pathological diagnosis revealed carcinoma in situ/intramucosal carcinoma in 20 patients,superficial submucosal infiltration in 5 patients,and deep submucosal infiltration into the muscular layer or deeper in 4 patients respectively.The misdiagnosis lasted(1.33±0.85)months.After diagnosis,individualized treatment plans were adopted based on tumor stage.Among the 20 patients in the pT1a stage,the lesions were completely removed by endoscopy,and no additional endoscopic treatment or surgery was required.Five patients with superficial submucosal invasion had negative margins in the postoperative pathology,and no additional surgical treatment was needed.Four patients who underwent endoscopic resection had pathological evidence of deep submucosal invasion and underwent laparoscopic radical surgery(D3 lymph node dissection),and 4 patients underwent surgical treatment.Follow-up showed that except for 1 patient who had tumor recurrence and received anti-tumor treatment,the others did not show recurrence.Conclusion The clinical manifestations of polypoid colorectal adenocarcinoma are atypical and prone to misdiagnosis.Clinicians should enhance their vigilance for this disease and optimize diagnostic strategies to reduce or avoid misdiagnosis.