[A Case of Recurrence of pT1a Rectal Cancer after 4 Years of EMR without Additional Resection Factors].

A 66-year-old man underwent endoscopic mucosal resection(EMR)for a polyp located in the rectosigmoid(RS)region. The pathological findings was tub1, T1a, ly0, v0, HM0 and VM0, and there were no factors indicating the need for additional treatment. Four years following the EMR procedure, a contrast-enhanced CT scan revealed an enlarged lymph node exhibiting contrast enhancement in the area of #252 lymph nodes. The patient was diagnosed with recurrent cancer, and laparoscopic high anterior resection with D3 dissection was performed. The patient had a good postoperative course and was discharged from the hospital on the seventh day after the surgery. The pathological diagnosis was a recurrence of rectal cancer characterized by an extramural tumor nodule without involvement of lymph node structures. Four courses of CAPOX were administered as adjuvant chemotherapy, and there has been no recurrence observed 2 years and 6 months after the surgery. The recurrence rate for endoscopically resected pT1a rectal cancer with no additional treatment considerations is relatively high, at 6.3%. Therefore, we consider that it is important to follow up the patient closely.