Endorectal ultrasound in the diagnosis of rectal cancer: Accuracy and criticies (original) (raw)
Endoscopic ultrasound: current role and future perspectives in managing rectal cancer patients
Journal of gastrointestinal and liver diseases : JGLD, 2011
As therapeutic regimens for rectal cancer have seen considerable changes, an accurate staging is mandatory for choosing the adequate strategy. Locoregional staging is the decisive factor in selecting patients for neoadjuvant chemoradiation therapy and for determining the extent of surgery. Endoscopic ultrasound (endorectal ultrasound--ERUS) is a very effective method for assessing the local extent of rectal cancer, especially regarding the depth of tumor infiltration. Although a significant limitation is represented by its lower accuracy for diagnosis of lymph node metastases, this is still a point of concern for other imaging tests as well. In this review we report the current data on ERUS, presenting both its advantages and limitations, and making a comparison to other staging methods. Recent developments of the technology that might enhance staging accuracy are also discussed.
Accuracy of Endorectal Ultrasonography in Preoperative Staging of Rectal Tumors
Diseases of The Colon & Rectum, 2002
PURPOSE: Preoperative staging of rectal tumors is considered essential to tailor treatment for individual patients. The aim of the present study was to evaluate the accuracy of endorectal ultrasonography in preoperative staging of rectal tumors. METHODS: Eleven hundred eighty-four patients with rectal adenocarcinoma or villous adenoma underwent endorectal ultrasonography evaluation at a single institution during a ten-year period. We compared the endorectal ultrasonography staging with the pathology findings based on the surgical specimens in 545 patients who had surgery (307 by transanal excision, 238 by radical proctectomy) without adjuvant preoperative chemoradiation. Comparisons between groups were performed using chi-squared tests and logistic regression analysis. RESULTS: Overall accuracy in assessing the level of rectal wall invasion was 69 percent, with 18 percent of the tumors overstaged and 13 percent understaged. Accuracy depended on the tumor stage and on the ultrasonographer. Overall accuracy in assessing nodal involvement in the 238 patients treated with radical surgery was 64 percent, with 25 percent overstaged and 11 percent understaged. CONCLUSION: The accuracy of endorectal ultrasonography in assessing the depth of tumor invasion, particularly for early cancers, is lower than previously reported. The technique is more precise in distinguishing between benign tumors and invasive cancers and between tumors localized to the rectal wall and tumors with transmural invasion. Differences in image interpretation may in part explain discrepancies in accuracy between studies.
Endorectal Ultrasonography and Treatment of Early Stage Rectal Cancer
World Journal of Surgery, 2000
The purpose of this study was to evaluate the accuracy of preoperative staging by endorectal ultrasonography (EUS) and its contribution to treatment of early stage rectal cancer (ESRC). The results of EUS for 154 consecutive patients with ESRC (pTis to pT2) were compared prospectively with histologic findings, assessed according to the TNM classification. Results of treatment selection and long-term outcomes were analyzed retrospectively. There were 35 patients histologically staged as pTis, 8 as pT1-slight (invasion confined to the superficial one-third of the submucosa), 37 as pT1-massive (invasion extending to the deeper submucosa), and 74 as pT2. The equipment used was an echoendoscope GF-UM2 or GF-UM3 (Olympus, Tokyo, Japan). Sensitivity/specificity/ overall accuracy rates for detection of slight submucosal invasion, massive submucosal invasion, and muscularis propria invasion were 99%/ 74%/96%, 98%/88%/97%, and 97%/93%/96%, respectively. Incidences of lymph node metastasis in pTis, pTis to pT1-slight, pT1, pT1-massive, and pT2 cases were 0%, 0%, 18%, 22%, and 30%, respectively. Incidences of lymph node metastasis in ESRCs staged by EUS (u) as uTis, uT1-slight, uT1-massive, uT2, and uT3 by EUS were 0%, 0%, 26%, 36%, and 64%, respectively. Sensitivity, specificity, and overall accuracy rates for detection of positive nodes in overall ESRCs were 53%, 77%, and 72%, respectively. Of the 43 patients with pTis to pT1-slight tumors, 22 underwent endoscopic polypectomy or local excision, 20 radical surgery, and 1 radical surgery after endoscopic polypectomy due to vascular invasion. All these patients are alive and all but one (who refused radical surgery due to vascular invasion after local excision and developed liver and lung metastases) are disease-free. Of the 37 patients with pT1-massive tumors, 34 underwent radical surgery and 3 transcoccygeal segmental resection. All these patients are alive disease-free except for one who died of peritoneal carcinomatosis after radical surgery. All patients with pT2 tumors underwent radical surgery. The overall 5-year survival rates for pTis, pT1, and pT2 cases were 100%, 98%, and 97%, respectively. EUS is an accurate method for evaluating invasion depth in ESRC. Patients with uTis or uT1-slight tumors staged by EUS are at low risk of positive nodes and good candidates for endoscopic polypectomy or local excision. Those with uT1-massive or uT2 lesions should be treated with a radical operation because of the high incidence of positive nodes.
How useful is rectal endosonography in the staging of rectal cancer?
World Journal of Gastroenterology, 2010
It is essential in treating rectal cancer to have adequate preoperative imaging, as accurate staging can influence the management strategy, type of resection, and candidacy for neoadjuvant therapy. In the last twenty years, endorectal ultrasound (ERUS) has become the primary method for locoregional staging of rectal cancer. ERUS is the most accurate modality for assessing local depth of invasion of rectal carcinoma into the rectal wall layers (T stage). Lower accuracy for T2 tumors is commonly reported, which could lead to sonographic overstaging of T3 tumors following preoperative therapy. Unfortunately, ERUS is not as good for predicting nodal metastases as it is for tumor depth, which could be related to the unclear definition of nodal metastases. The use of multiple criteria might improve accuracy. Failure to evaluate nodal status could lead to inadequate surgical resection. ERUS can accurately distinguish early cancers from advanced ones, with a high detection rate of residual carcinoma in the rectal wall. ERUS is also useful for detection of local recurrence at the anastomosis site, which might require fine-needle aspiration of the tissue. Overstaging is more frequent than understaging, mostly due to inflammatory changes. Limitations of ERUS are operator and experience dependency, limited tolerance of patients, and limited range of depth of the transducer. The ERUS technique requires a learning curve for orientation and identification of images and planes. With sufficient time and effort, quality and accuracy of the ERUS procedure could be improved.
British Journal of Surgery, 1985
The ability of intrarectal ultrasound to recognize the local extent of disease was investigated in 23 patients with histologically proven adenocarcinoma of the lower two-thirds of the rectum before operation. Two probes, 12cm long, working at a frequency of 3.5 and 7.5 MHz, were used. The results were compared with those of pre-operative computed tomography (CT) and with the pathological report of the resected specimens. Sonography correctly staged 20 of 23 tumours with two false negatives and one false positive, while CT correctly staged 19 of 23 tumours with two false negatives and two false positives. The results of ultrasound were found to be as accurate as those of CT; the low cost and simple use of ultrasound makes it preferable in the pre-operative assessment of the depth of invasion of rectal cancer. In addition, intrarectal ultrasound was routinely performed in 42 patients, operated on for rectal cancer by means of sphincter-saving procedures, at variable intervals in the first 2 years postoperatively. Eight local recurrences were recognized and confirmed by CT. Based on the low cost, reliability and simple use, intrarectal ultrasound is proposed as first examination for local recurrence detection in the follow-up of patients with low anterior resection for rectal cancer.
Endorectal ultrasound detection of focal carcinoma within rectal adenomas
The American Journal of Surgery, 2004
The misdiagnosis of a rectal adenoma by biopsy and subsequent finding of invasive cancer after transanal excision is associated with a number of pitfalls. Problems include suboptimal therapy for a potentially curable cancerous lesion, potential tumor transgression of the local site with increased chance for local recurrence, and increased potential for more radical surgery or adjuvant chemoradiation. The utility of endorectal ultrasound (ERUS) in guiding treatment decisions of rectal villous adenomas has been reported, but series are small and are from single institutions. To determine the utility of ERUS in the diagnosis of rectal adenomas, we compared diagnosis made by biopsy alone to diagnosis made by a combination of biopsy and ERUS. Methods: A systematic literature review was performed by way of a PubMed search to find articles with the following terms: "biopsynegative rectal adenomas," "preoperative ERUS diagnosis," and "surgical histopathology." Five studies met the criteria, thus providing data for 258 adenomas. A quantitative meta-analysis was performed on the data. Results: Among the 258 biopsy-negative rectal adenomas, 24% had focal carcinoma on histopathology. ERUS correctly established a cancer diagnosis in 81% (95% confidence interval 69 to 90) of these misdiagnosed lesions. Thus, ERUS diagnosis of biopsy-negative rectal adenomas could be expected to decrease the need for additional surgery and other associated problems caused by misdiagnosis from 24% to 5%. Conclusions: ERUS is a useful adjunct to biopsy in the preoperative workup of rectal villous adenomas, and we recommend its routine use. Accurate preoperative assessment allows the surgeon to counsel the patient appropriately regarding the best operation, the perioperative risks, and the chances of local recurrence.
Detection and staging of primary rectal cancer by transrectal sonography
Prilozi / Makedonska akademija na naukite i umetnostite, Oddelenie za biološki i medicinski nauki = Contributions / Macedonian Academy of Sciences and Arts, Section of Biological and Medical Sciences, 2005
This study is a prospective clinical investigation that includes 587 patients aged on average 55.3 years with symptoms such as perirectal pain, rectal bleeding, and change in bowel habit and tenesmus that had been investigated at the Clinic. Rectal cancer was diagnosed by endoscopy and pathohistologically confirmed in 377 cases. Demonstration of tumor, extension into perirectal fat and lymph node involment were evaluated. Tumors were successfully imaged by endorectal ultrasound. According to the endosonographical results patients were divided into 3 groups: operable, consisting of 168 pts (29%), inoperable group of 205 pts. (35%) and control group with 214 pts (36%). However, transrectal sonography as a usable supplementary method has to provide approximate sensitivity as the method to which it is supplementary, in fact to be able to detect the lesion that was proved beyond doubt in this study. The results suggest that transrectal sonography has an important role in the determinatio...
Clinical and endorectal ultrasound staging of circumferential rectal cancers
Journal of Medical Imaging and Radiation Oncology, 2008
Circumferential rectal cancers present at a more advanced stage than those located in a single quadrant. Although accurate staging is an important aspect of the preoperative management of the patient with a rectal cancer, the clinical and radiological staging of this subgroup of rectal cancer patients has been poorly studied. All patients with a rectal cancer were assessed clinically (by digital rectal examination and rigid sigmoidoscopy) before the radiological assessment by endorectal ultrasound (ERUS). Data collected included tumour height (distance from anal verge in centimetre) and tumour type (circumferential or non-circumferential). Radiological tumour staging was with the TNM system. Fifty-nine subjects (33 men, 26 women; median age 65 years (range 38-86 years)) were identified with a circumferential rectal cancer. Mean height of the cancer was 8 AE 0.4 cm (standard error of the mean; range 2-13 cm). Forty-two cancers were palpable, and 17 cancers were impalpable. All cancers assessed clinically as circumferential were confirmed as circumferential on ERUS scanning. Tumour stage as assessed by ERUS was either T3 (n = 57) or T4 (n = 2). Nodal status was N0 (n = 29) and N1 (n = 30). All rectal cancers assessed as circumferential on clinical examination have an ERUS stage of T3 or greater.
Medical ultrasonography, 2015
Endoscopic ultrasound is recommended for rectal cancer staging. Transrectal ultrasound approach is able to overcome one of the limitations of this technique regarding circumferential rectal stenosis. Prior intrarectal administration of a small amount of fluid contrast agent optimizes the method, making it easier to distinguish the layers of the rectal wall and tumor formation. Endoscopic ultrasound focuses on the gray-scale mode. Additional procedures provide useful information for tumor assessment: Doppler ultrasound helps identify chaotic intratumoral vascularization; 3D ultrasound allows the assessment and accurate measurement of the tumor; elastography can identify focal tumor dysplasia within adenomas; contrast-enhanced ultrasound allows characterization of tumor microvasculature. Even if they are not as accurate in distinguishing rectal wall layers, cross-sectional imaging techniques (CT, MRI) can identify the anatomical relationships of advanced locoregional cancers, as well ...