摘要
BACKGROUND Differential diagnosis of colorectal intramucosal tumors from invasive adenocarcinoma is important in clinical practice due to the different risks of lymph node metastasis and different treatment options.The phenomenon of a colorectal adenoma with part of the gland entering the submucosa is known as pseudoinvasion of the adenoma,which is a major challenge for pathological diagnosis.It is essential to raise awareness of colorectal adenoma with submucosal pseudoinvasion clinically to avoid overtreatment.CASE SUMMARY We describe a case of rectal adenoma with submucosal pseudoinvasion in a 48-year-old man.The patient was admitted to Jinhua People's Hospital due to a change in stool habit for 5 d.We performed colonoscopy,and the results suggested a submucosal bulge approximately 1.0 cm×1.0 cm in size in the rectum 8 cm from the anal verge,with red surface erosion.Ultrasound colonoscopy was also performed and a homogeneous hypoechoic mass about 0.52 cm×0.72 cm in size was seen at the lesion,protruding into the lumen with clear borders and invading the submucosa.Endoscopic surgery was then performed and the pathological specimen showed a tubular adenoma with high-grade intraepithelial neoplasia(intramucosal carcinoma)involving the adenolymphatic complex.In addition,we performed a literature review of rectal tubular adenoma with submucosal pseudoinvasion to obtain a deeper understanding of this disease.CONCLUSION The aim of this study was to improve awareness of this lesion for clinicians and pathologists to reduce misdiagnosis.
