A Case with Rectal Cancer Relapses After Clinical Complete Remission Following Neoadjuvant Chemoradiotherapy.

Despite advancements in diagnosis and therapy, relapse of rectal cancer after clinical complete remission (cCR) remains a frequent event. The key factors influencing the treatment strategy for the management of patients achieving cCR following neoadjuvant chemoradiotherapy (Neo-CRT) remain to be identified. We present the case of a 64-year-old man with rectal cancer. The patient was initially admitted to the hospital in September 2011 with a 3-month history of change in his stools. Following his re-hospitalization in November 2011, a biopsy specimen of the neoplasm suggested the presence of rectal adenocarcinoma; laboratory investigations also revealed elevated levels of carcinoembryonic antigens (CEA; carbohydrate antigen 199) in the serum. Subsequently, the patient received Neo-CRT, as well as symptomatic and supportive treatment. The level of serum CEA returned to normal, without signs of swollen lymph nodes in the pelvic cavity. The patient was diagnosed with rectal cancer based on the elevated level of serum CEA, colonoscopy, and contrast-enhanced magnetic resonance imaging. He relapsed 4 months after cCR following Neo-CRT and underwent laparoscopic Miles' surgery in April 2013. The relapse may have been mainly attributed to residual tumor cells. This case report and literature review may contribute to the clinical recognition of treatment for patients with rectal cancer achieving cCR following Neo-CRT.