EUS in the preoperative staging and restaging of advanced rectal cancer

Background: Endoscopic ultrasonography (EUS) is highly accurate for locoregional staging of rectal cancer (RC). Purpose: The aim of the study was to evaluate both accuracy and clinical impact of EUS in the staging and restaging [after neoadjuvant chemotherapy+radiotherapy (NAT)] of patients (pts) with RC at our Institution. Material And Methods: From 1994 to 2005, 189 pts with RC underwent EUS for locoregional staging at our Institution. There were 108 men, and 81 women, with a mean age of 60 years (40–80). The EUS was performed using an echo-colonoscope Olympus â CF UM 20. After EUS staging, the pts were divided in 2 groups. Group 1 included 118 pts who underwent surgery directly. In group 2 there were 71 pts who underwent NAT before surgery. In group 2, EUS was performed before and after NAT. In all cases, T and N stages at EUS were compared with the correspondent pTN stages. Results: In group 1 EUS showed an overall accuracy of 82% for T stage. When T stages were analyzed separately, EUS showed an accuracy of 74% for T1, 74% for T2, 91% for T3 and 66% for T4, respectively. Fourteen (12%) RC were overstaged (OS), while 7 (6%) RC were understaged (US). Moreover, EUS showed an overall accuracy of 70% for N stage, with a sensitivity of 73% and a specificity of 68%. In group 2, EUS restaging (EUS-R) after NAT had an overall accuracy for T of 63% (24% OS; 8% US, 4% not evaluable). Overall accuracy of EUS-R for N stage was 60% (7.0% OS; 3% US; 29% not evaluable), with a sensitivity of 63% and a specificity of 60%. Conclusions: Our data shows that EUS is useful in order to select those pts who undergo directly surgery and those who need NAT before surgery. In the latter subset, EUS-R changed the therapeutic strategy in 11 pts (15%), who underwent anterior resection instead of a Miles operation. After NAT, R-EUS restaging was less satisfactory