Current Role of Endoscopic Ultrasonography in Rectal Cancer Evaluation During Multidisciplinary Therapy

We report the case of a patient presenting in the Gastroenterology Department with intermittent rectal bleeding during the past year. A diagnosis of a low rectal adenocarcinoma was based on colonoscopy examination with biopsies, and staging procedures included transrectal endoscopic ultrasonography and magnetic resonance imaging of the abdomen and pelvis (cT2N0M0). Consequently the patient was referred for pre-operative chemoradiotherapy, achieving a complete clinical response as documented by repeated EUS and MRI examinations. Transanal endoscopic microsurgery with pathological assessment of the resected specimen revealed residual adenocarcinoma, highlighting the limitations of current imaging methods, and the constant need of technological improvements.