How useful is endorectal ultrasound in the management of early rectal carcinoma?

Endorectal ultrasonography (EUS) is used to T stage early rectal tumours and select patients to whom transanal endoscopic microsurgery (TEM) could be offered. Published papers have shown that EUS can have good accuracy, but there is little literature on how EUS influences patient management. The study aim is to ascertain the value of EUS in the management of early rectal tumours. Patients with adenomas/early rectal carcinoma being considered for TEM were prospectively studied. Each patient underwent EUS. The surgeon recorded the expected T stage, confidence level of the T stage and management plan for each patient on a proforma before and after the ultrasound result was revealed. Comparison was made between the ultrasound stage and final pathological stage where available. Ninety-six patients were referred over 2 years. Nine were out of reach of the rigid probe and were excluded. Proformas were completed on 53/87 patients (age range 28-87 years, mean age 66 years, 30 males/23 females). Forty-eight patients had a pathological report to compare with the EUS T stage. Ultrasound agreed with the pathological T staging in 43 patients (90 %). Patient management was changed in five patients. In 30 % of (16/53) patients, EUS increased the confidence level for T staging. Although EUS has a high accuracy in predicting the T stage of early rectal cancers, it never changes the management plan for lesions thought to be benign. It seldom changes the pre-operative selection process when clinical examination is considered with other imaging modalities (MRI/CT). EUS should be reserved for answering specific questions in difficult cases rather than for all patients.