• Early rectal cancer
• Enema
• Magnetic resonance imaging
• Reader confidence
• Sensitivity and specificity

• early diagnosis
• enema
• lymphatic metastasis
• magnetic resonance imaging
• neoplasm staging
• rectal neoplasms

• Norwegian society of medical Radiology

• high-grade dysplasia
• rectal polyp
• transanal endoscopic microsurgery

• Local surgery
• Oncological outcome
• Rectal adenoma
• Rectal cancer
• Rectal surgery
• Transanal endoscopic microsurgery

• Adenoma/surgery
• Digestive System Surgical Procedures
• Humans
• Microsurgery/methods
• Neoplasm Recurrence, Local/surgery
• Prospective Studies
• Rectal Neoplasms/pathology
• Rectal Neoplasms/surgery
• Retrospective Studies
• Treatment Outcome

• Spanish “Fondo de Investigación Sanitaria: Ministerio de Sanidad y Consumo
• Universidad de Zaragoza

• Humans
• Liver Neoplasms/diagnostic imaging
• Magnetic Resonance Imaging
• Neoplasm Staging
• Rectal Neoplasms/diagnostic imaging
• Rectal Neoplasms/pathology
• Tomography, X-Ray Computed

• endorectal ultrasonography
• imaging
• magnetic resonance imaging
• rectal cancer
• staging

• Chemoradiation
• Chemotherapy
• Radiotherapy
• Total neoadjuvant therapy
• Toxicity

• Early rectal cancer
• imaging
• pre-operative

• Alpha Particles
• Antineoplastic Agents/therapeutic use
• Chemoradiotherapy, Adjuvant
• Consensus
• Delphi Technique
• Evidence-Based Practice
• Humans
• Magnetic Resonance Imaging
• Neoplasm Recurrence, Local/prevention & control
• Neoplasm Staging/methods
• Patient Selection
• Postoperative Complications/prevention & control
• Proctectomy/methods
• Proctoscopy
• Quality of Life
• Rectal Neoplasms/diagnostic imaging
• Rectal Neoplasms/pathology
• Rectal Neoplasms/surgery
• Rectal Neoplasms/therapy
• Societies, Medical
• Standard of Care
• Treatment Outcome
• United States
• Watchful Waiting

• P30 CA072720 NCI NIH HHS

• Endorectal ultrasonography
• Rectal cancer
• Shear wave elastography
• Staging

• Adult
• Aged
• Aged, 80 and over
• Elasticity Imaging Techniques/methods
• Endosonography/methods
• Female
• Humans
• Magnetic Resonance Imaging/methods
• Male
• Middle Aged
• Neoplasm Staging
• Prospective Studies
• Rectal Neoplasms/diagnostic imaging
• Rectal Neoplasms/pathology
• Rectum/diagnostic imaging
• Rectum/pathology
• Reproducibility of Results
• Retrospective Studies

• endoanal ultrasound
• endorectal ultrasound
• perineal ultrasound

• Circumferential resection margin
• Endorectal ultrasound
• MRI
• TME surgery

• early stage rectal cancer
• local excision
• adjuvant
• neoadjuvant
• appropriateness criteria

• Chemotherapy, Adjuvant
• Guidelines as Topic
• Humans
• Lymphatic Metastasis
• Neoadjuvant Therapy
• Patient Selection
• Radiotherapy, Adjuvant
• Radiotherapy, Conformal/methods
• Rectal Neoplasms/diagnosis
• Rectal Neoplasms/pathology
• Rectal Neoplasms/surgery
• Rectal Neoplasms/therapy

• R50 CA275877 NCI NIH HHS

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.

• Rectal cancer
• Staging
• Endoscopic ultrasonography
• Accuracy
• Therapeutic strategy

• Colorectal Cancer
• Diagnosis
• Locoregional Invasion
• Neoadjuvant Therapy

Endorectal ultrasonography (ERUS) and magnetic resonance imaging (MRI) allow exploring the morphology of the rectum in detail. Use of such data, especially assessment of the rectal wall, is an important tool for ascertaining the perianal fistula localization as well as stage of the cancer and planning it appropriate treatment, as stage T3 tumors are usually treated with neoadjuvant therapy, whereas T2 tumors are initially managed surgically. The only advantage of ERUS over MRI is the possibility of assessing T1 tumors that could be treated by transanal endoscopic microsurgery. However, MRI is better for visualizing most radiological prognostic features in rectal or anal cancer such as a circumferential resection margin less than 1 mm, T stage at T1-T2 or T3 tumors with extramural extension less than 5 mm, absence of extramural vascular invasion, N stage at N0/N1, and tumors located in the middle or upper third of the rectum. It can also evaluate the intersphincteric space or levator ani muscle involvement. Increased signal on diffusion weighted imaging (DWI) and low apparent diffusion coefficient (ADC) values as well as an irregular contour and heterogeneous internal signal intensity seem to predict the involvement of pelvic lymphatic nodes better than their size alone. Computed tomography as well as other examination techniques, including digital rectal examination, contrast edema, recto- and colonoscopy, are less useful in staging of rectal cancer but still are very important screening tools.

• Anal canal
• Fistula
• Rectal neoplasms
• Ultrasonography

Rectal cancer is a common cancer and a major cause of mortality in Western countries. Accurate staging is essential for determining the optimal treatment strategies and planning appropriate surgical procedures to control rectal cancer. Endorectal ultrasonography (EUS) is suitable for assessing the extent of tumor invasion, particularly in early-stage or superficial rectal cancer cases. In advanced cases with distant metastases, computed tomography (CT) is the primary approach used to evaluate the disease. Magnetic resonance imaging (MRI) is often used to assess preoperative staging and the circumferential resection margin involvement, which assists in evaluating a patient’s risk of recurrence and their optimal therapeutic strategy. Positron emission tomography (PET)-CT may be useful in detecting occult synchronous tumors or metastases at the time of initial presentation. Restaging after neoadjuvant chemoradiotherapy (CRT) remains a challenge with all modalities because it is difficult to reliably differentiate between the tumor mass and other radiation-induced changes in the images. EUS does not appear to have a useful role in post-therapeutic response assessments. Although CT is most commonly used to evaluate treatment responses, its utility for identifying and following-up metastatic lesions is limited. Preoperative high-resolution MRI in combination with diffusion-weighted imaging, and/or PET-CT could provide valuable prognostic information for rectal cancer patients with locally advanced disease receiving preoperative CRT. Based on these results, we conclude that a combination of multimodal imaging methods should be used to precisely assess the restaging of rectal cancer following CRT.

• Rectal cancer
• Multimodality
• Imaging
• Staging
• Restaging

• Chemoradiotherapy, Adjuvant
• Diffusion Magnetic Resonance Imaging
• Humans
• Magnetic Resonance Imaging
• Multimodal Imaging
• Neoadjuvant Therapy
• Neoplasm Invasiveness
• Neoplasm Metastasis
• Neoplasm Staging
• Positron-Emission Tomography
• Rectal Neoplasms/diagnosis
• Rectal Neoplasms/pathology
• Recurrence
• Tomography, X-Ray Computed
• Treatment Outcome
• Ultrasonography

• Colon cancer
• Consensus
• Guidelines
• Rectal cancer

Local excision is increasingly performed for “early stage” rectal cancer in the US; however, local recurrence after local excision has become a controversial issue in Western countries. Local recurrence is considered to originate based on the type of tumor and procedure performed, and in surgical margin-positive cases. This review focuses on the inclusion criteria of “early” rectal cancers for local excision from the Western and Japanese points of view. “Early” rectal cancer is defined as T1 cancer in the rectum. Only the tumor grade and depth of invasion are the “high risk” factors which can be evaluated before treatment. T1 cancers with sm1 or submucosal invasion <1,000 μm are considered to be “low risk” tumors with less than 3.2 % nodal involvement, and are considered to be candidates for local excision as the sole curative surgery. Tumors with a poor tumor grade should be excluded from local excision. Digital examination, endoscopy or proctoscopy with biopsy, a barium enema study and endorectal ultrasonography are useful for identifying “low risk” or excluding “high risk” factors preoperatively for a comprehensive diagnosis. The selection of an initial local treatment modality is also considered to be important according to the analysis of the nodal involvement rate after initial local treatment and after radical surgery.

Transanal endoscopic microsurgery as a local therapy option for rectal neoplasms is a tissue-sparing technique that protects the anal sphincter. The present retrospective analysis reports the course of observation after local excision of adenomas and T1 low-risk carcinomas using transanal endoscopic microsurgery.

In a retrospective analysis we examined data on 279 patients for local recurrence. A total of 144 patients had a rectal adenoma (n = 103) or a R0 resection of low-risk T1 carcinomas (n = 41). In this collective, we also examined parameters concerning perioperative management, complications, intraoperative blood loss and duration of hospital stay.

Patients with adenoma were on average 64.9 (range 37 to 90) years old; 83.5% of the adenomas were located 3 to 11 cm from the anocutaneous line. In adenoma patients the recurrence rate was 2.9% for an observation period of 21.8 months. The postoperative course was without any complications in 98.1% of patients.

Patients with T1 low-risk carcinoma were 64.6 (range 30 to 89) years old. In all cases, an R0 resection could be performed. The recurrence rate was 9.8% for an observation period of 34.4 months. In this group the postoperative course was free of complications in 97.6% of patients.

The high efficacy of transanal endoscopic microsurgery ensures minimally invasive treatment of adenomas and low-risk T1 carcinomas with low complication rates and a low rate of therapeutic failure.

AIM: To evaluate the agreement between transrectal ultrasound (TRUS) and magnetic resonance imaging (MRI) in classification of ≥ T3 rectal tumors.

METHODS: From January 2010 to January 2012, 86 consecutive patients with ≥ T3 tumors were included in this study. The mean age of the patients was 66.4 years (range: 26-91 years). The tumors were all ≥ T3 on TRUS. The sub-classification was defined by the penetration of the rectal wall: a: 0 to 1 mm; b: 1-5 mm; c: 6-15; d: > 15 mm. Early tumors as ab (≤ 5 mm) and advanced tumors as cd (> 5 mm). All patients underwent TRUS using a 6.5 MHz transrectal transducer. The MRI was performed with a 1.5 T Philips unit. The TRUS findings were blinded to the radiologist performing the interpretation of the MRI images and measuring the depth of extramural tumor spread.

RESULTS: TRUS found 51 patients to have an early ≥ T3 tumors and 35 to have an advanced tumor, whereas MRI categorized 48 as early ≥ T3 tumors and 38 as advanced tumors. No patients with tumors classified as advanced by TRUS were found to be early on MRI. The kappa value in classifying early versus advanced T3 rectal tumors was 0.93 (95% CI: 0.85-1.00). We found a kappa value of 0.74 (95% CI: 0.63-0.86) for the total sub-classification between the two methods. The mean maximal tumor outgrowth measured by TRUS, 5.5 mm ± 5.63 mm and on MRI, 6.3 mm ± 6.18 mm, P = 0.004. In 19 of the 86 patients the following CT scan or surgery revealed distant metastases; of the 51 patients in the ultrasound ab group three (5.9%) had metastases, whereas 16 (45.7%) of 35 in the cd group harbored distant metastases, P = 0.00002. The odds ratio of having distant metastases in the ultrasound cd group compared to the ab group was 13.5 (95% CI: 3.5-51.6), P = 0.00002. The mean maximal ultrasound measured outgrowth was 4.3 mm (95% CI: 3.2-5.5 mm) in patients without distant metastases, while the mean maximal outgrowth was 9.5 mm (95% CI: 6.2-12.8 mm) in the patients with metastases, P = 0.00004. Using the MRI classification three (6.3%) of 48 in the MRI ab group had distant metastases, while 16 (42.1%) of the 38 in the MRI cd group, P = 0.00004. The MRI odds ratio was 10.9 (95% CI: 2.9-41.4), P = 0.00008. The mean maximal MRI measured outgrowth was 4.9 mm (95% CI: 3.7-6.1 mm) in patients without distant metastases, while the mean maximal outgrowth was 11.5 mm (95% CI: 7.8-15.2 mm) in the patients with metastases, P = 0.000006.

CONCLUSION: There is good agreement between TRUS and MRI in the pretreatment sub-classification of ≥ T3 tumors. Distant metastases are more frequent in the advanced group.

• Ultrasound
• Magnetic resonance imaging
• Rectal cancer
• Tumor staging
• Metastases

• Adult
• Aged
• Aged, 80 and over
• Endosonography/methods
• Female
• Gels
• Humans
• Male
• Middle Aged
• Neoplasm Invasiveness
• Neoplasm Staging
• Predictive Value of Tests
• Rectal Neoplasms/diagnostic imaging
• Rectal Neoplasms/pathology
• Rectal Neoplasms/surgery
• Sensitivity and Specificity

Clinical management of rectal cancer patients relies on pre-operative staging. Studies however continue to report moderate degrees of over/understaging as well as inter-observer variability. The aim of this study was to determine the sensitivity, specificity and accuracy of tumor size for predicting T and N stages in pre-operatively untreated rectal cancers.

We examined a test cohort of 418 well-documented patients with pre-operatively untreated rectal cancer admitted to the University Hospital of Basel between 1987 and 1996. Classification and regression tree (CART) and logistic regression analysis were carried out to determine the ability of tumor size to discriminate between early (pT1-2) and late (pT3-4) T stages and between node-negative (pN0) and node-positive (pN1-2) patients. Results were validated by an external patient cohort (n = 28).

A tumor diameter threshold of 34 mm was identified from the test cohort resulting in a sensitivity and specificity for late T stage of 76.3%, and 67.4%, respectively and an odds ratio (OR) of 6.67 (95%CI:3.4-12.9). At a threshold value of 29 mm, sensitivity and specificity for node-positive disease were 94% and 15.5%, respectively with an OR of 3.02 (95%CI:1.5-6.1). Applying these threshold values to the validation cohort, sensitivity and specificity for T stage were 73.7% and 77.8% and for N stage 50% and 75%, respectively.

Tumor size at a threshold value of 34 mm is a reproducible predictive factor for late T stage in rectal cancers. Tumor size may help to complement clinical staging and further optimize the pre-operative management of patients with rectal cancer.

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.

• Rectal cancer
• Colorectal cancer
• Staging
• Endorectal ultrasonography
• Endorectal ultrasound
• Accuracy
• Tumor invasion
• Nodal metastases
• Other rectal tumors
• Diagnostics