Comparision between transrectal ultrasonography and computed tomography with rectal inflation of gas in preoperative staging of lower rectal cancer

Abstract

Computed tomography with rectal air insufflation was compared with transrectal ultrasonography (TRUS) in 63 patients. The CT protocol involved pre- and postcontrast scans with 5 mm slice thickness following air insufflation in IV antiperistaltic agent. Of the patients, 79 % were scanned in the prone position. Results of the preoperative examinations were compared with the histological findings. The CT examination had an accuracy rate of 74 %, predicting perirectal spread with a sensitivity of 83 % and a specificity of 62 %, whereas the corresponding figures for TRUS were 83, 91 and 67 %. The accuracy, sensitivity and specificity of CT and TRUS for nodal involvement were 57, 56, 57, 66, 68 and 64 %-respectively. These findings confirm that TRUS is more accurate than CT in local tumour (T) staging and in detecting nodal (N) spread. However, the appropriate CT technique shows spread of tumour outside the rectal wall and locoregional lymph nodes with reasonable accuracy. Lymphatic spread correlated with nodal size. TRUS and CT correctly staged only 57 and 43 %, respectively, of cases with nodal metastases with maximum diameter of 5 mm. TRUS sometimes overstaged perirectal growth of tumour in 7 patients, due to inflammation (5 patients) or incorrect positioning of the balloon in relation to the tumour surface (2 patients).

Rectal tumour staging: MR imaging using pelvic phased-array and endorectal coils vs endoscopic ultrasonography

“…Several previous studies have demonstrated that TRUS is more accurate than CT in assessing preoperative local staging of rectal cancer [7,18]. In a recent large multicenter study comparing CT and MR, better prediction of transmural tumour penetration was found by CT than by MR (accuracy 74 vs 58 %) [22]; however, it was suggested that recent developments in MR could affect these results.…”

“…In rectal cancer staging, both transrectal ultrasonography (TRUS), CT and MR imaging have all been evaluated for assessing both tumour infiltration in the bowel wall and loco-regional lymph node metastases [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21]. Despite initial promising results and subsequent technical developments of the methods, the overall results in large series of patients indicate that presently routine staging of rectal cancer cannot be justified, because the accuracy to predict tumour penetration and lymph node metastases is limited [22,23,24,25].…”

Accuracy of endorectal ultrasound after preoperative radiochemotherapy in locally advanced rectal cancer

“…Endorectal ultrasound and CT scan represent the main imaging methods for prediction [4,13]. Endorectal ultrasound has been proved superior to CT scan in the evaluation of local tumor progression [12,25]. By the use of endorectal ultrasound, the T-category can be predicted with up to 90% accuracy, whereas correct predictions with CT scan reach only 70% accuracy [12,25].…”

Präoperative Diagnostik beim lokal fortgeschrittenen Rektumkarzinom (≥T3 oder N+)

“…Zahlreiche Untersuchungen zeigten, dass die rES als dynamische Untersuchungsmethode bei der Beurteilung der Infiltrationstiefe (uT), insbesondere bei uT1-Malignomen, und des lokoregionalen Nodalstatus (uN) der CT-Diagnostik überlegen ist [38,41,63,67,68,70,76]. Gemeinsam mit der präoperativen Biopsathistologie beeinflusst die rES maßgeblich das therapeutisch-chirurgische Vorgehen [2,45,65].…”