Effectiveness of endoluminal sonography in the identification of occult local rectal cancer recurrences

Consensus and controversies regarding follow-up after treatment with curative intent of nonmetastatic colorectal cancer: a synopsis of guidelines used in countries represented in the European Society of Coloproctology

AIM

It is common clinical practice to follow patients for a period of years after treatment with curative intent of nonmetastatic colorectal cancer, but follow-up strategies vary widely. The aim of this systematic review was to provide an overview of recommendations on this topic in guidelines from member countries of the European Society of Coloproctology, with supporting evidence.

METHOD

A systematic search of Medline, Embase and the guideline databases Trip database, BMJ Best Practice and Guidelines International Network was performed. Quality assessment included use of the AGREE-II tool. All topics with recommendations from included guidelines were identified and categorized. For each subtopic, a conclusion was made followed by the degree of consensus and the highest level of evidence.

RESULTS

Twenty-one guidelines were included. The majority recommended that structured follow-up should be offered, except for patients in whom treatment of recurrence would be inappropriate. It was generally agreed that clinical visits, measurement of carcinoembryoinc antigen and liver imaging should be part of follow-up, based on a high level of evidence, although the frequency is controversial. There was also consensus on imaging of the chest and pelvis in rectal cancer, as well as endoscopy, based on lower levels of evidence and with a level of intensity that was contradictory.

CONCLUSION

In available guidelines, multimodal follow-up after treatment with curative intent of colorectal cancer is widely recommended, but the exact content and intensity are highly controversial. International agreement on the optimal follow-up schedule is unlikely to be achieved on current evidence, and further research should refocus on individualized 'patient-driven' follow-up and new biomarkers.

Role of endoscopic ultrasonography in the loco-regional staging of patients with rectal cancer

The prognosis of rectal cancer (RC) is strictly related to both T and N stage of the disease at the time of diagnosis. RC staging is crucial for choosing the best multimodal therapy: patients with high risk locally advanced RC (LARC) undergo surgery after neoadjuvant chemotherapy and radiotherapy (NAT); those with low risk LARC are operated on after a preoperative short-course radiation therapy; finally, surgery alone is recommended only for early RC. Several imaging methods are used for staging patients with RC: computerized tomography, magnetic resonance imaging, positron emission tomography, and endoscopic ultrasound (EUS). EUS is highly accurate for the loco-regional staging of RC, since it is capable to evaluate precisely the mural infiltration of the tumor (T), especially in early RC. On the other hand, EUS is less accurate in restaging RC after NAT and before surgery. Finally, EUS is indicated for follow-up of patients operated on for RC, where there is a need for the surveillance of the anastomosis. The aim of this review is to highlight the impact of EUS on the management of patients with RC, evaluating its role in both preoperative staging and follow-up of patients after surgery.

Utility of EUS following endoscopic polypectomy of high-risk rectosigmoid lesions

Background:

The utility of endoscopic ultrasound (EUS) compared with standard white light endoscopy (WLE) following recent polypectomy of high-risk colorectal polyps is unknown.

Objective:

To assess the incremental yield of EUS after endoscopic polypectomy of a high-risk rectal lesion.

Design:

Retrospective cohort.

Setting:

Tertiary referral center.

Materials and Methods:

Patients referred for EUS following attempted endoscopic resection of a high-risk rectal neoplasm, defined as a tubulovillous adenoma, tubular adenoma with high-grade dysplasia, carcinoid, carcinoma in-situ or adenocarcinoma (CA).

Interventions:

Sigmoidoscopy ± mucosal biopsy and EUS ± fine-needle aspiration (FNA) to evaluate for: (1) Residual polyp/tumor in the rectal wall or (2) peritumoral adenopathy.

Main Outcome:

Sensitivity and specificity for detection of residual neoplasia for WLE ± biopsy (WLE/BX) and EUS ± FNA for cancer (CA group) or benign disease (non-CA group). The incremental yield of EUS defined as: (1) Residual intramural neoplasia not present on WLE ± BX and; (2) abnormal peritumoral adenopathy.

Results:

A total of 70 patients (mean age 64 ± 11 years, 61% male) with a final diagnosis of CA (n = 38) and non-CA (n = 32) were identified. There was no difference between the sensitivity and specificity of WLE alone (65% and 84%), WLE with biopsy (71% and 95%), and EUS (59% and 84%), for the detection of residual neoplasia (P > 0.05 for all). EUS identified 3 masses missed by WLE, all in the CA group. A malignant (n = 2) or benign (n = 3) node was identified in 5 (13%) CA patients; EUS-FNA in two showed residual malignancy in one and a reactive lymph node (LN) in one. No LNs were identified in the non-CA patients.

Limitations:

Retrospective design, incomplete follow-up in some patients.

Conclusion:

Following endoscopic polypectomy of high-risk rectal neoplasia, the incremental yield of EUS compared with WLE/BX for evaluation of residual disease appears limited, especially in patients with benign disease.

Endorectal ultrasound: its role in the diagnosis and treatment of rectal cancer

With development over the past 25 years of new surgical techniques and neoadjuvant therapy regimens for rectal cancer, physicians now have a range of treatment options that minimize morbidity and maximize the potential for cure. Accurate pretreatment staging is critical, ensuring adequate therapy and preventing overtreatment. Many options exist for staging primary rectal cancer. However, endorectal ultrasound (ERUS) remains the most attractive modality. It is an extension of the physical examination, and can be performed easily in the office. It is cost effective and is generally well tolerated by the patient, without need for general anesthesia. The authors discuss the data currently available on ERUS, including its accuracy and limitations, as well as the technical aspects of performing ERUS and interpreting the results. They also discuss new ultrasound technologies, which may improve rectal cancer staging in the future.

Endoscopic ultrasound in the diagnosis, staging and management of colorectal tumors

Endoscopic ultrasound (EUS) has evolved as a useful technique for imaging and intervention in the colon and rectum. This article reviews the clinical applications of EUS for imaging and intervention in colorectal cancer, with an emphasis on the most recent clinical studies.

Ultraschall in der Tumornachsorge

According to the guidelines, ultrasonography (US) is now established as the cross-sectional imaging technique of choice in postoperative care of colorectal carcinoma. Although conventional percutaneous US is inferior to computed tomography (CT) and magnetic resonance imaging (MRI) for detecting hepatic metastases, the application of specific contrast media has significantly increased sensitivity and specificity to 87% and 88%, respectively. The combination of US and CT/MRI achieves the highest detection rates. During follow-up of rectal carcinoma, in up to 20% of locoregional recurrences are diagnosed solely by endorectal sonography and result in repeat resection with curative intention. In noncolorectal carcinoma, US is recommended in the guidelines for following up hepatocellular carcinoma and malignant thyroid disease, but the available data are insufficient to support those recommendations.

Recent developments in the role of endoscopic ultrasonography in diseases of the colon and rectum

PURPOSE OF REVIEW

Endoscopic ultrasound has evolved as a useful technique for imaging and intervention in a variety of gastrointestinal and extraintestinal diseases including diseases of the colon and rectum. This paper will review recent developments in endoscopic ultrasound for colorectal diseases.

RECENT FINDINGS

Recent studies have shown significant clinical impact of endoscopic ultrasound in rectal cancer staging. Iliac lymph node evaluation by endoscopic ultrasound-guided fine needle aspiration may further expand the role of endoscopic ultrasound in rectal cancer. Three-dimensional endoscopic ultrasound may help decrease some of the errors of staging with two-dimensional endoscopic ultrasound and may further improve staging accuracy. Recent studies have confirmed continued problems with re-staging rectal cancer after chemoradiation. Endoscopic ultrasound-fine needle aspiration can be helpful in detecting local recurrence of rectal cancer and has been shown to be useful in evaluation of subepithelial masses of the colon and rectum and evaluation of rectosigmoid endometriosis.

SUMMARY

Endoscopic ultrasound continues to be useful for a variety of conditions of the colon and rectum with recent studies confirming its clinical impact as well as expanding its role into newer indications. Assessment for residual cancer after chemoradiation is still problematic and hopefully technological developments in ultrasound in the future may help in improving the accuracy of endoscopic ultrasound in this situation.

Preoperative loco-regional imaging in rectal cancer

Preoperative staging of rectal cancer can influence the choice of surgery and the use of neoadjuvant therapy. This review evaluates the use of endorectal ultrasound (ERUS) and magnetic resonance imaging (MRI) in the local staging of rectal cancer. Staging for distant metastases is beyond the scope of this review. A MEDLINE search for published work in English between 1984-2004 was carried out by entering the key words of ERUS, MRI and preoperative imaging and rectal cancer. Initially, 867 articles were retrieved. Abstracts were reviewed and papers selected according to the inclusion criteria of a minimum of 50 patients and papers published in English. Papers focusing on preoperative chemoradiotherapy and distal metastases were excluded. Thirty-one papers were included in the systematic review. The examination techniques and images obtained are discussed and the respective accuracy is reviewed. ERUS and MRI have complementary roles in the assessment of tumour depth. Ultrasound has an overall accuracy of 82% (T1, 2, 40-100%; T3, 4, 25-100%) and is particularly useful for early localized rectal cancers. MRI has an accuracy of 76% (T1, 2, 29-80%; T3, 4, 0-100%) and is useful in more advanced disease by providing clearer definition of the mesorectum and mesorectal fascia. Both methods have similar accuracy in the assessment of nodal metastases. Ultrasound is more operator dependent and accuracies improve with experience, but it is more portable and accessible than MRI. Improvements in technology and increased operator experience have led to more accurate preoperative staging. ERUS and MRI are complementary and are most accurate for early localized cancers and more advanced cancers, respectively.

An update on imaging of colorectal cancer

Screening of asymptomatic average-risk patients for presence of colon cancer and early detection in precursor stages is of great interest to general population. Comprehensive evaluation of symptomatic or high-risk patients represents another important clinical focus. Available techniques for total colon imaging, rectal cancer staging and the role of positron emission tomography are discussed.

The postoperative surveillance of patients with colon cancer and rectal cancer

BACKGROUND

Colon cancer is relatively common; however, the results of treatment have marginally improved over the last half century. Though about 85% of patients have colorectal tumors resected with curative intent, a significant number of these patients will eventually die from cancer. As a result, many clinicians have advocated intensive follow-up in such patients as an attempt to increase survival.

DATA SOURCES

A review of the literature focusing on studies that have specifically addressed postoperative surveillance programs in patients with colorectal cancer was conducted. Only studies with level A evidence were included. Further references were obtained through cross-referencing the bibliography cited in each work.

CONCLUSION

One of the six prospective randomized studies demonstrated a statistically significant survival benefit. Undoubtedly, survival benefits can be shown with a well-designed evidence-based follow-up strategy. However, well-designed large prospective multi-institutional randomized studies are needed to establish a consensus for follow-up.

Endorectal ultrasound-directed biopsy: a useful technique to detect local recurrence of rectal cancer

AIMS

This study assesses the value of endorectal ultrasound (ERUS)-directed biopsy in detecting local recurrence of rectal cancer.

METHODS

We reviewed the records of patients undergoing ERUS by a single surgeon for surveillance after treatment of rectal adenocarcinoma. Lesions suggestive of local recurrence underwent ERUS-assisted core-needle biopsy (EAB) via a proctoscope after precise ERUS localization or direct ERUS-guided biopsy (EGB) via a B&K Medical probe.

RESULTS

From 1991 to 2003, 525 patients underwent 2,490 surveillance ERUS. Of these patients, 51 underwent 62 biopsy sessions: 36 EGB and 26 EAB. The mean age of patients was 67.2 years (range 38-93 years); 22 (43%) were female. Only 11 patients (22%) had undergone prior radical resection of their primary tumor. No patient experienced a complication from the biopsies despite five being anticoagulated. Of 39 patients whose cancer recurrence was documented during follow-up, 32 (82%) were diagnosed at the initial biopsy session, and in five (13%), recurrence was detected only with ERUS. The combined sensitivity, specificity, and accuracy of EAB and EGB in detecting recurrence was 83, 100, and 87%, respectively. In 26 patients with local recurrence, resection was performed with curative intent.

CONCLUSION

ERUS with biopsy is useful in detecting local recurrence after treatment of rectal cancer. It is safe, with a high diagnostic yield. It may be particularly useful in patients at higher risk for local recurrence (i.e., after endocavitary radiation and local excision) and may allow early detection of local recurrence, thereby permitting attempts at curative resection.

Development of a cost-effective system for digital off-line analysis of transrectal ultrasound

BACKGROUND

Transrectal ultrasound (TRUS) is the most sensitive and accurate technique for preoperative staging and follow-up of rectal cancer. One of the most relevant problems of this technique is that the assessment of TRUS is possible only during real-time examination. Furthermore, interpretation of the ultrasound findings is difficult and requires long experience. We show the development of a new, cost-effective software solution for off-line examination and documentation of transrectal ultrasound.

METHODS

The ultrasound device is connected to a frame-grabber card in a standard PC. Video capturing is done using a freeware software solution and various video codecs. The whole examination course is recorded. The examiner only has to concentrate on producing an artifact-free realization of the examination.

RESULTS

The software solution offers a flexible review of each individual "frame" of the investigation on the personal computer, very similar to CT and MRI scans. Infiltration depth and lymph node status can be assessed at any time, independently of the investigation and the investigator. The picture quality is excellent even if a lossy codec is used. It is not necessary to do definitive assessment of the TRUS during the examination.

CONCLUSIONS

This new technique gives a cost-effective possibility for high-quality off-line staging, re-examination, re-evaluation, and documentation of rectal cancer. TRUS becomes an examiner-independent objective examination technique for staging and follow-up of rectal cancer.

Clinical applications of endoscopic ultrasound to oncology

Endoscopic ultrasound (EUS) is a useful imaging modality in patients with certain gastrointestinal malignancies as well as lung cancer. In many cases, EUS has been shown to have superior staging accuracy compared with other imaging techniques such as computed tomography, magnetic resonance imaging and positron emission tomography. This article will review the role of EUS in diagnosing and staging esophageal, rectal, pancreatic and lung cancers as well as subepithelial lesions. Newer therapeutic applications of EUS, namely endoscopic mucosal resection for removal of localized lesions as well as celiac plexus neurolysis for pain control, will also be discussed.

Screening and surveillance of colorectal cancer

Although colorectal cancer (CRC) is the second leading cause of cancer deaths in the United States, it is preventable. Screening modalities include fecal occult blood testing, flexible sigmoidoscopy, double-contrast barium enema, and colonoscopy. Colonoscopy allows effective detection and removal of precursor adenomatous polyps and is the dominant CRC screening modality. Emerging technologies include CT and MR colonography and fecal DNA tests. Effective and cost-effective surveillance after polypectomy and curative CRC resection requires balancing the protective effect of polypectomy while maximizing intervals between examinations; thus, estimation of the risk of recurrence determines the intensity of surveillance for individual patients.

Endoscopic ultrasound for luminal malignancies

Luminal gastrointestinal (GI) tract cancers are responsible for substantial morbidity and mortality. Since the first pairing of ultrasonography with endoscopy in 1980, technologic advances and the increased availability of trained endosonographers have propelled endoscopic ultrasonography (EUS) to the forefront of luminal GI cancer staging. In this article we discuss the role of EUS for evaluating luminal GI cancers.

ASGE guideline: the role of endoscopy in the diagnosis, staging, and management of colorectal cancer

This is one of a series of statements discussing the utilization of GI endoscopy in common clinical situations. The Standards of Practice Committee of the American Society for Gastrointestinal Endoscopy prepared this text. In preparing this guideline, a MEDLINE literature search was performed, and additional references were obtained from the bibliographies of the identified articles and from recommendations of experts. When little or no data exist from well-designed prospective trials, emphasis is given to results from large series and reports from recognized experts. Guidelines for appropriate utilization of endoscopy are based on a critical review of the available data and expert consensus. Further controlled clinical studies are needed to clarify aspects of this statement and revision needed to clarify aspects of this statement and revision may be necessary as new data appear. Clinical consideration may justify a course of action at variance to the recommendations.

Endorectal ultrasound in rectal cancer

Accurate staging of rectal carcinoma is crucial for planning surgery and the indication for adjuvant therapy. Although computed tomography and magnetic resonance imaging are very sensitive in the detection metastastic disease, local staging of rectal cancer with these techniques has been disappointing. Endorectal ultrasound (EUS) remains the most accurate method for staging of rectal cancer. High accuracy rates in the assessment of the depth of infiltration (T stage) (80-90%) and in the determination of the lymph node status (70-80%) have been confirmed in several studies. Continued research and development has made the instrumentation for EUS more accurate and user-friendly. New techniques that have contributed significantly to the evolution of EUS include three-dimensional EUS, high-frequency miniprobes and transrectal ultrasound-guided biopsy techniques. Further improvement can be expected by contrast enhancement with microbubbles and colour Doppler imaging.

Clinical impact of on-site cytopathology interpretation on endoscopic ultrasound-guided fine needle aspiration

OBJECTIVES

Endoscopic ultrasound-guided fine needle aspiration (EUS-guided FNA) is becoming a preferred modality for diagnosing and staging GI and mediastinal malignancies. Although experts advocate on-site cytopathology assessment for tissue sample adequacy, there are few data to support this claim. Our goal was to determine whether on-site cytopathology interpretation improves the diagnostic yield of EUS-guided FNA.

METHODS

EUS-guided FNA results from two university hospital centers were reviewed and compared. At center 1, where EUS-guided FNA was performed with a cytopathologist on site, the results of 108 consecutive patients were evaluated. At center 2, where a cytopathologist is unavailable, the results of 87 consecutive patients were reviewed. One endoscopist performed all procedures at both institutions. Cytologic diagnoses were categorized as positive or negative for malignancy, suspicious for malignancy, atypical/indeterminate, or unsatisfactory. The number of repeat procedures, needle passes, medication use, target site, age, and sex were compared between the two sites.

RESULTS

Patients at center 2 were older (p = 0.04) and predominantly female (p = 0.03). Pancreas was the most common target site at center 2, whereas thoraco-abdominal nodes were the most common at center 1 (p = 0.0001). Patients at center 1 had a diagnosis of positive or negative for malignancy more frequently (p = 0.001) and were less likely to have an unsatisfactory specimen (p = 0.035) or repeat procedure, although the latter was not significant (p = 0.156).

CONCLUSION

On-site cytopathology interpretation improves the diagnostic yield of EUS-guided FNA. EUS centers should allocate resources to cover for on-site cytopathology evaluation.

Endoscopic ultrasound for rectal cancer

The application of EUS has improved the way we evaluate and manage patients with rectal cancer. EUS has substantially greater sensitivity than CT in detecting advanced T stage tumors. Such improved sensitivity results in changes in preoperative therapy that would not otherwise have occurred without EUS. Although the addition of FNA provides little incremental effect on patient management, it carries the most potential for impacting management in those patients with early T stage disease, and its use should be considered in this subgroup of patients. Whether the accurate staging ability of EUS translates into improved outcomes in terms of reduced recurrence rates and ultimately prolonged survival remains uncertain. This will require further long-term outcome studies focusing on the endpoint of tumor recurrence and patient survival.

Endoscopic ultrasound

Indications and the clinical utility of endosonography have evolved as new technology, such as linear array echoendoscopes and EUS-guided fine needle aspiration, has emerged. The most noteworthy of the EUS applications are for cancer staging; including rectal, pancreatic, lung, and esophageal malignancies. There is little doubt that EUS is a powerful tool for cancer imaging, but its clinical impact in patient care and management has yet to be validated in prospective outcome studies. Other imaging modalities such as positron emission tomography (PET), dual-phased helical CT, and MR imaging technology will undoubtedly provide increasingly accurate diagnostic and staging information for gastrointestinal diseases. EUS imaging alone may assume a less significant role in relation to these noninvasive modalities in the future. EUS-guided FNA, as well as therapeutic EUS applications, will likely continue to expand in scope and play an important role in clinical medicine for many years to come.