Transit endoscopic ultrasound of colorectal cancer using a 12 MHz catheter probe

Abstract

The objective of this study was to examine the accuracy of a 12 MHz ultrasound catheter probe in the pre-operative staging of colorectal cancer by assessing the depth of tumour infiltration and involvement of pericolonic lymph nodes. 159 patients with colorectal cancer who underwent ultrasound examination with a 12 MHz catheter probe were studied prospectively. The results of this imaging procedure were compared with the histological findings of the resected specimens. The accuracy of the 12 MHz ultrasound catheter probe for depth of invasion (T category) was 85% (131/154) for all tumours, 87% (46/53) for pT1 tumours, 60% (9/15) for pT2 tumours, 89% (74/83) for pT3 tumours and 67% (2/3) for pT4 tumours. The accuracy for tumours of the rectum and colon was 81% and 89%, respectively. The accuracy of the probe for nodal staging (N category) was 67% (76/114) overall. The sensitivity was 70% (33/47), the specificity 64% (43/67), the positive predictive value 58% (33/57) and the negative predictive value 75% (43/57). Endoscopic ultrasound using a 12 MHz catheter probe accurately assessed tumour stage, although nodal staging remained suboptimal. This method may aid in the selection of treatment for patients with colorectal cancer.

3D echoendoscopy and miniprobes for rectal cancer staging

“…2) for T1 staging, which is in agreement with previous reports (21,22). With regard to T2 staging, 3D was superior to mp-EUS, which tended to overstage tumors (12,16,17,(22)(23)(24). A very high accuracy for T3 staging was reported for 3D or mp-EUS (12,16,17,(23)(24)(25)(26), whereas mp-EUS had the lowest accuracy in relation to the higher ultrasound frequency for T4 staging, which is in line with current evidence (17,(24)(25)(26)(27).…”

“…With regard to T2 staging, 3D was superior to mp-EUS, which tended to overstage tumors (12,16,17,(22)(23)(24). A very high accuracy for T3 staging was reported for 3D or mp-EUS (12,16,17,(23)(24)(25)(26), whereas mp-EUS had the lowest accuracy in relation to the higher ultrasound frequency for T4 staging, which is in line with current evidence (17,(24)(25)(26)(27). The use of 3D for T staging of rectal cancer had the best accuracy with mp and allowed the staging of stenosing tumors, although with some limitations for large masses (e.g., T4 staging).…”

Diagnostic performance of EUS for evaluating the invasion depth of early colorectal cancers

“…When clear EUS images were obtained, the rate of correctly differentiating Tis and T1a cancers from T1b cancer has been reported to be as high as approximately 90%. [5][6][7][8][9][10][11][12][13][14] In our study, the rate of correct differential diagnosis was 89%, indicating good diagnostic results. One study did not support the diagnostic accuracy of EUS for evaluating whether endoscopic resection was indicated for colorectal tumors, 28 but that study was small and used an early-model echocolonoscope with a low frequency.…”

Preoperative Staging of Rectal Cancer: Role of Endorectal Ultrasound

“…In differentiating mucosa neoplasias (M)/ submucosal cancers with slight invasion (SM-s) from non M/SM-s the accuracy of ERUS in villous and nonvillous lesions was 66% and 96%, respectively. Akahoshi et al (58) improved the accuracy of ERUS by using a high-frequency ultrasound probe (12MHz). The depth of invasion was correctly assessed in 87% (46/53) of pT1 tumors.…”