Assessment of local stage in rectal cancer using endorectal ultrasonography (EUS)

Preoperative staging of rectal cancer is essential for the selection of the optimal treatment. This study aims to evaluate the accuracy of endorectal ultrasonography (EUS) in local staging of rectal cancer.

During a 4-year period, 33 patients with biopsy-proven rectal cancer underwent evaluation of the invasion of the rectal wall, the mesorectal lymph nodes status and the pelvic organs using EUS. We compared the EUS findings (uTN) to the histopathology examination of the resected specimens (pTN) according to TNM classification.

Most patients had T3 tumours. Overall accuracy in assessing the depth of rectal wall invasion (T) and the lymph node status was 79% and 59% respectively. Two patients previously treated by preoperative chemoradiation were correctly staged only for N stage.

EUS is a valuable diagnostic tool in local staging of rectal cancer. Progressively increasing experience will overcome the obstacles in accurate interpretation of ultrasound images.