Localization of the peritoneal reflection in the pelvis by endorectal ultrasound

Background: Large adenomas and low-risk rectal carcinomas (T₁) that are localized distal of the pelvic peritoneal reflection (PPR) are treated by transanal excision. However, the location of the PPR varies widely and cannot be detected reliably by preoperative methods. Therefore, we evaluated the value of endorectal ultrasound (EUS) for the prediction of an intraperitoneal location of rectal tumors. Methods: Fourteen patients with rectal tumors measuring ≤15 cm from the anal verge were examined by EUS. If peristalsis beyond the rectal wall or any intraperitoneal fluid was seen at the proximal tumor edge, the lesion was classified as localized above or in the level of the PPR. During the operation, the surgeon determined whether the upper end of the tumor reached the PPR. Results: In each of our 14 patients, the prediction by EUS was correct. In two patients, a small rectal tumor was excised with an electric sling during rectoscopy, but the polyp bases were not free of dysplastic epithelial tissue. The point where these two polyps were removed could be visualized by endoscopy but not by EUS. Once the relevant area was marked with a titanic endoclip, EUS was able to predict the resection place in relation to the PPR in these two patients as well. Conclusions: Although this knowledge would be very important for the therapeutic strategy of small rectal tumors, it is impossible to determine the location of a rectal tumor with regard to the PPR either clinically or by endoscopy. EUS provides this information with high reliability. Thus, we recommend EUS as the method of choice for predicting the location of the PPR. Received: 13 January 1998/Accepted: 14 April 1998     

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

Objectives: Factors limiting the accuracy of endorectal ultrasound in staging, locally advanced primary rectal cancer after preoperative neoadjuvant radiochemotherapy (RCT) were evaluated. Methods: Patients (n= 84) with initial locally advanced rectal cancer (uT3/uT4) undergoing R0 resection were investigated after preoperative treatment that combined radiotherapy up to 45 Gy with two cycles of chemotherapy (5-FU and leucovorin on d 1–5 and 22–28). At 4 to 6 weeks after completion of RCT and before tumor resection, preoperative endoluminal ultrasound was performed. Results: The accuracy to predict the depth of tumor infiltration (T-category) was found to correlate with downstaging. The T-category was correctly staged before surgery in 15 of the 51 responders (29%) and in 27 of 33 nonresponders (82%), whereas misinterpretation occurred in 36 of the responders (71%) and in 6 of the nonresponders (18%) (p < 0.001). Neither tumor distance from anal verge nor tumor location correlated with the staging accuracy. Lymph node involvement was correctly assessed in 48 patients (57%). Wall invasion was correctly ascertained in 42 patients (50%), with under estimation in 11 patients (13%) and overestimation in 31 patients (37%). Conclusions: After radiochemotherapy, endosonography does not provide a satisfactory accuracy for preoperative staging of rectal cancer. New interpretation and diagnostic criteria are needed for the prediction of treatment response. Received: 28 February 1999/Accepted: 2 April 1999     

Preoperative adjuvant radiation with chemotherapy for rectal cancer: Its impact on stage of disease and the role of endorectal ultrasound

Background: Preoperative adjuvant radiation combined with chemotherapy is a recent development in the management of patients with rectal cancer invading perirectal tissue and regional lymph nodes. This study was performed to assess the impact of preoperative adjuvant therapy in patients judged by endorectal ultrasound to have extramural invasion of rectal cancer and/or regional lymph node involvement on tumor regression in bowel wall and lymph nodes. The predictive value of ultrasound in staging wall penetration and lymph node involvement after preoperative adjuvant therapy was also assessed. Methods: Patients (n=43) were selected by ultrasound to have preoperative irradiation (4,500–5,040 cGy over 5–6 weeks). In 30 patients this was combined with 5-fluorouracil, 370 mg/m², for 5 days in the first and last weeks of irradiation. Pretreatment ultrasound was compared with pathologic findings in the resected specimen in all patients. Twenty-one were assessed by ultrasound after adjuvant therapy and findings compared with histology. Results: Downstaging was seen in 23 (53%) patients with wall invasion and in 23 (72%) of 32 patients with lymph node involvement. Overall, downstaging was achieved in 30 (70%). Positive predictive values of ultrasound after irradiation were 72% and 56% for wall penetration and lymph node status, respectively. Negative predictive values of ultrasound after irradiation were 100% and 82%, respectively. Conclusion: In the majority of patients with rectal cancer invading perirectal tissues or lymph nodes, lesions may be downstaged by preoperative adjuvant therapy. Endorectal ultrasound after adjuvant therapy for rectal cancer is of a lesser predictive value chiefly because of overstaging.     

Initial experience with stereoscopic visualization of three-dimensional ultrasound data in surgery

Initial in vivo and in vitro experiments were performed to evaluate the feasibility of stereoscopically displaying three-dimensional (3D) ultrasound data from neurosurgery, laparoscopic surgery, and vascular surgery. Stereoscopic visualization was illustrated by four video sequences, which can be downloaded from http://www.us.unimed.sintef.no/. These sequences show a brain tumor, hepatic arteries in relation to the gallbladder, a model that mimics a neuroendoscope in a cyst, and a ``flight' into model of an artery with an intima flap. The experiments indicate that stereoscopic display of ultrasound data is feasible when there is sufficient contrast between the objects of interest and the surrounding tissue. True 3D vision improves perception, thus enhancing the ability to understand complex anatomic structures such as irregular lesions and tortuous vessels. Received: 5 August 1999/Accepted: 14 October 1999/Online publication: 22 May 2000     

三维肛管直肠腔内超声在肛瘘诊治中的应用

目的 探讨三维肛管直肠腔内超声定位肛瘘内口、显示瘘管走行的价值.方法 2008年11月至2010年1月应用三维肛管直肠腔内超声检查肛瘘患者127例,在三维立体模块中根据声像图特征进行内口定位、瘘管走行追踪.结果 定位内口116例,准确率91.3%(116/127),其中112例患者内口开口于齿线处,4例发现内口于直肠壶腹;127例患者定位主管,准确率100%(127/127),其中经括约肌瘘75例,括约肌间瘘47例,括约肌上瘘2例,括约肌外瘘3例;定位支管37例,准确率100%(37/37).结论 应用三维肛管直肠腔内超声检查肛瘘,能够准确定位内口、显示瘘管走行,能为临床治疗方法的选择提供必要的诊断依据.     

Minimally invasive surgical staging for esophageal cancer

Background: The incidence of esophageal adenocarcinoma is increasing in the United States, and the 5-year survival rate is dismal. Preliminary data suggest that conventional imaging is inaccurate in staging esophageal cancer and could limit accurate assessment of new treatments. The objective of this study was to compare minimally invasive surgical staging (MIS) with conventional imaging for staging esophageal cancer. Methods: Patients with potentially resectable esophageal cancer were eligible. Staging by conventional methods used computed tomography (CT) scan of the chest and abdomen, and endoscopic ultrasound (EUS), whereas MIS used laparoscopy and videothoracoscopy. Conventional staging results were compared to those from MIS. Results: In 53 patients, the following stages were assigned by CT scan and EUS: carcinoma in situ (CIS; n= 1), I (n= 1), II (n= 23), III (n= 20), IV (n= 8). In 17 patients (32.1%), MIS demonstrated inaccuracies in the conventional imaging, reassigning a lower stage in 10 patients and a more advanced stage in 7 patients. Conclusions: In 32.1% of patients with esophageal cancer, MIS changed the stage originally assigned by CT scan and EUS. Therefore, MIS should be applied to evaluate the accuracy of new noninvasive imaging methods and to assess new therapies for esophageal cancer. Received: 5 April 1999/Accepted: 15 March 2000/Online publication: 12 July 2000     

Comparative study of three-dimensional and conventional endorectal ultrasonography used in rectal cancer staging

Background

Three-dimensional (3D) imaging offers improved knowledge of various anatomic structures and tumors by providing 3D images. This prospective study was performed to verify whether 3D endorectal ultrasonography (EUS) enhances the accuracy of rectal cancer staging, as compared with conventional EUS.

Methods

Using both 3D and conventional EUS, 33 consecutive patients with operable rectal cancer were preoperatively staged. A rigid 3D probe with a scanner was used for 3D EUS, and a rigid endorectal probe with a scanner was used for conventional EUS.

Results

The accuracy of 3D EUS was 90.9% for pT2 and 84.8% for pT3, whereas that of conventional EUS was 84.8% and 75.8%, respectively, thereby showing no difference between these two methods. The lymph node metastasis was accurately predicted by 3D EUS in 28 patients (84.8%), whereas conventional EUS predicted the disorder in 22 patients (66.7%). The difference was not statistically significant. The average infiltration grade of the circumference on transverse 3D EUS scans was associated closely with advancement of the TNM stage (p<0.001–0.006) and lymph node metastasis (p=0.003). The presence of a cone-shaped surface on the deep tumor border correlated with the infiltration grade shown on all of the sectional displays (p<0.001–0.042) and with advancement of the TNM stage (p=0.018).

Conclusions

Although the findings did not show 3D EUS to have a significant advantage over conventional EUS for the accurate evaluation of rectal cancer, a numeric advantage may possibly be statistically significant in a further study with larger cases. Furthermore, stereoscopic visualization provided easier and complete understanding of both focal lesions and lymph nodes.

     

The use of intraoperative ultrasound in laparoscopic adrenal surgery

Background: Laparoscopic adrenalectomy has been shown to be a safe and effective therapy for benign adrenal lesions. We review our experience with this procedure, including the use of laparoscopic ultrasound. Methods: We retrospectively reviewed our experience with 36 patients who underwent resection of 42 adrenal glands. Data gathered included preoperative evaluation and diagnosis, operative time, blood loss, complications, and follow-up status. Laparoscopic ultrasound was used to guide dissection and characterize a variety of adrenal lesions. Results: Thirty-five of 36 patients underwent successful laparoscopic adrenalectomy. There was one conversion to the open procedure in a patient with bilateral adrenal metastases from an endometrial cancer. For the bilateral laparoscopic procedure, the operative time averaged 262 mins, blood loss was 160 cc, and hospital stay was 3.0 days. For unilateral cases, operative time averaged 193 min, blood loss was 108 cc, and hospitalization was 1.1 days. Six patients experienced perioperative complications, most of which were minor and transient. Laparoscopic ultrasound was useful to define anatomy and to identify the adrenal vein, especially on the left side. Conclusions: Laparoscopic adrenalectomy is the procedure of choice for benign adrenal disease. Laparoscopic ultrasound is useful to localize and aid in the dissection of the left adrenal vein. Received: 24 December 1998/Accepted: 12 February 1999     

Efficacy of 3-dimensional endorectal ultrasonography compared with conventional ultrasonography and computed tomography in preoperative rectal cancer staging

BACKGROUND: This study was performed to verify reports of the decreased accuracy of endorectal ultrasonography (EUS) in preoperative staging of rectal cancer, and to compare the efficacy of 3-dimensional (3D) EUS with that of 2-dimensional (2D) EUS and computed tomography (CT). METHODS: Eighty-six consecutive rectal cancer patients undergoing curative surgery were evaluated by 2D EUS, 3D EUS, and CT scan. RESULTS: The accuracy in T-staging was 78% for 3D EUS, 69% for 2D EUS, and 57% for CT (P < .001-.002), whereas the accuracy in evaluating lymph node metastases was 65%, 56%, and 53%, respectively (P < .001-.006). Examiner errors were the most frequent cause of misinterpretation, occurring in 47% of 2D EUS examinations and in 65% of 3D EUS examinations. By eliminating examiner errors, the accuracy rates in T-staging and lymph node evaluation could be improved to 88% and 76%, respectively, for 2D EUS, and to 91% and 90%, respectively, for 3D EUS. Conical protrusions along the deep tumor border on 3D images were correlated closely with infiltration grade, advanced T-stage, and lymph node metastasis. CONCLUSIONS: We found that 3D EUS showed greater accuracy than 2D EUS or CT in rectal cancer staging and lymph node metastases. Concrete 3D images based on tumor biology appear to provide more accurate information on tumor progression.     

Rectal endosonography can distinguish benign rectal lesions from invasive early rectal cancers

Objective To determine whether an experienced ultrasound examiner, using good ultrasound equipment with high multifrequency probes, can discriminate between a high grade or low grade dysplastic adenoma (pT0) and very early invasive rectal cancers (pT1). Subjects and methods Sixty consecutive patients with clinically possibly pT0 or pT1 rectal tumours referred for transanal local excision underwent endorectal ultrasound examination. Lesions where the endorectal ultrasound image showed the mucosal layer to be expanded but the submucosal layer to be intact (uT0) were considered to represent a low grade or high grade dysplasia adenoma (pT0). An irregularity or disruption of the submucosal layer (uT1) was considered to characterize early invasive rectal cancers (pT1). The ultrasound staging was compared with the histological staging made on the basis of the diagnoses in the excised specimens. Results The histopathological diagnoses were: invasive rectal cancer (n = 18, 10 pT1, 4 pT2, 4 pT3 cancers); high grade dysplastic adenoma (n = 21); low grade dysplastic adenoma (n = 18); non adenomatous benign lesions (n = 3). Endorectal ultrasound incorrectly classified two of the invasive cancers (both pT1 tumours) as noninvasive lesions. Five of 42 pT0 tumours were overstaged as uT1 tumours. Overstaging was more common in patients who had undergone a previous excision and in tumours with peritumoral inflammation and desmoplastic reaction. The sensitivity of endorectal ultrasound with regard to invasive cancer was 89% (16/18), specificity 88% (37/42), positive predictive value 76% (16/21), negative predictive value 95% (37/39), and accuracy 88% (53/60). Among pT0 and pT1 tumours, the corresponding figures were 80% (8/10), 88% (37/42), 62% (8/13), 95% (37/39), and 87% (45/52). Conclusion Endorectal ultrasound can distinguish between noninvasive lesions and invasive rectal cancers clinically of stage pT0 or pT1.     

Cost-effectiveness of different diagnostic strategies in patients with nonresectable upper gastrointestinal tract malignancies

Background and methods: Using a simple model, this retrospective study evaluated the cost-effectiveness of different diagnostic strategies used for pretherapeutic detection of patients with disseminated or locally nonresectable upper gastrointestinal tract malignancies (UGIM). Of 162 consecutive UGIM patients referred for treatment, 73 (45%) had disseminated or locally nonresectable disease, and these patients were eligible for evaluation. Results: The noninvasive diagnostic strategies (computed tomography [CT] with ultrasonography [US] and endoscopic ultrasonography [EUS]) had a low procedure cost, but a diagnostic strategy based on CT with US or CT with US and laparoscopy was not cost-effective. The inclusion of endoscopic or laparoscopic ultrasonography seemed necessary to the provision of a cost-effective strategy because both techniques had a high diagnostic accuracy combined with a low cost. A change in diagnostic strategy from CT with US to CT with US and EUS resulted in a net saving regarding the cost of each additional nonresectable patient detected, but this strategy still required up to 20% futile explorative laparotomies. Conclusions: The combination of endoscopic and laparoscopic ultrasonography was cost-effective and had no complications in this study. We use this strategy as our standard in the pretherapeutic evaluation of UGIM patients. Received: 27 November 1998/Accepted: 12 July 1999     

Preoperative abdominal ultrasound may be misleading in risk stratification for presence of common bile duct abnormalities

Background: Following the advent of laparoscopic cholecystectomy (LC), the preoperative predictors of common bile duct (CBD) abnormalities became more important in perioperative decision making. Preoperative transabdominal ultrasound (US) is used to assess the preoperative risks associated with CBD abnormalities. This study attempts to determine the sensitivity and specificity of US in determining CBD abnormalities in patients prior to LC. Methods: US measurements of the CBD diameter and presence of stones were ascertained from radiology reports in 100 patients who had LC with a routine intraoperative cholangiogram (IOC). The same information was obtained from the patients' IOC. A supraduodenal CBD diameter of >8 mm was considered dilated. Results: US demonstrated a sensitivity of 25% and a specificity of 70% for the detection of CBD dilatation compared to IOC. The sensitivity of US for predicting CBD dilatation was 55% when the IOC-derived diameter was >10 mm and 100% when it was >15 mm. The overall sensitivity of US for detection of stones was 10%; it improved to 17% in patients with a dilated CBD on US. Conclusions: Preoperative ultrasound is neither sensitive nor specific for detecting CBD dilatation or presence of stones. A negative preoperative US report may be misleading in risk stratification for the presence of these CBD abnormalities. In order to avoid missing any CBD pathology, we recommend the routine use of intraoperative cholangiography. Received: 30 July 1999/Accepted: 24 September 1999     

The examiner's learning effect and its influence on the quality of endoscopic ultrasonography in carcinoma of the esophagus and gastric cardia

Background: The preoperative diagnosis of tumors of the esophagus and the gastric cardia is an important element in their stage-oriented therapy. The goal of the present study was to evaluate the accuracy of endosonographic ultrasound (EUS) and to test its usefulness in tumor staging and the assessment of operability. Methods: A total of 139 tumors were scanned via EUS by one examiner ≤14 days prior to resection (TNM staging per UICC, 1987). Results: The accuracy for completely traversable tumors was 60.8% for T1, 82.1% for T2, 77.5% for T3, and 33% for T4 stages. This accuracy was somewhat reduced in cases of nontraversable tumor stenosis (51.9%). In T staging, a significant case-dependent improvement in accuracy to 89.5% was found; this was regarded as a learning effect. In N staging, we considered only those tumors that were resected by the transthoracic approach with systematic node dissection and complete EUS (n= 80). N-stage accuracy (T1–T4) was 71.3%, and no improvement could be shown. To assess operability, discrimination between T1/T2 and T3/T4 tumors is crucial. Accuracy, sensitivity, and specifity can thus be improved significantly. Conclusions: The quality of EUS depends on the experience of the examiner. Reliable results can be obtained after >75 examinations have been done. EUS is a valuable tool in tumor staging when it is performed by an experienced examiner or under the direct supervision of such a person. Received: 28 April 1998/Accepted: 14 October 1998     

The use of diagnostic laparoscopy supported by laparoscopic ultrasonography in the assessment of pancreatic cancer

Background: Pancreatic resection with curative intent is possible in a select minority of patients with carcinomas of the pancreatic head. Diagnostic laparoscopy supported by laparoscopic ultrasonography combines the proven benefits of staging laparoscopy with high-resolution intraoperative ultrasound, thus allowing the surgeon to perform a detailed assessment of the pancreatic cancer. Methods: In a prospective study of 26 patients with obstructive jaundice from a carcinoma of the head of the pancreas, the curative resectability of tumors was assessed by ultrasound (26 cases), computerized tomography (26 cases), endoscopic ultrasound (16 cases), and a combination of diagnostic laparoscopy and laparoscopic ultrasound (26 cases). Results: The findings of ultrasound and computerized tomography were comparable: 50% of patients were excluded from curative resection. Endoscopic ultrasound provided precise information on the primary tumors. The accuracy of the combined diagnostic laparoscopy and laparoscopic ultrasound, when compared with ultrasound, computerized tomography, and endoscopic ultrasound, was better with respect to minute peritoneal or hepatic metastasis: 80.7% (or a further 30.7%) of patients did not qualify for curative resection. Conclusions: Diagnostic laparoscopy supported by laparoscopic ultrasonography enables detection of previously unsuspected metastases; thus, needless laparotomy can be avoided. It should therefore be considered the first step in any potentially curative surgical procedure. Received: 12 April 1997/Accepted 30 April 1998     

Preoperative magnetic resonance staging of rectal cancer with an endorectal coil and dynamic gadolinium enhancement

BACKGROUND: The aim of the study was to assess the value of endorectal coil magnetic resonance imaging (MRI) with gadolinium enhancement in the preoperative staging of rectal cancer. METHODS: In addition to standard evaluation, patients with rectal lesions were assessed by MRI obtained with a pelvic phased-array coil in combination with an endorectal coil. RESULTS: The study group comprised 29 patients with rectal cancer staged with an endorectal coil who had surgery without preoperative adjuvant therapy. In addition to standard T1- and T2-weighted images, dynamic contrast-enhanced images were acquired in all patients. Considerable interobserver variation was noted, particularly for pathological tumour stage pT1 or pT2 (kappa = 0.36). Compared with pathological findings, endorectal MRI correctly staged nine patients, overstaged 16 and understaged four. Whilst lymph node metastases were accurately detected in 70 per cent of patients, the positive predictive value was only 58 per cent. CONCLUSION: MR staging of rectal cancer with an endorectal coil and gadolinium enhancement is inaccurate for early tumours (stage T1 or T2) and is associated with a considerable degree of interobserver variation for individual scan sequences.     

Laparoscopically assisted transsacral resection of rectal cancer with primary anastomosis

Background: The management of rectal cancer has been changing to include more sphincter-sparing procedures. We report our initial experience with a new technique incorporating laparoscopy and a transsacral approach for low or midlevel rectal cancer. Here, we tried to determine whether this sphincter-sparing method could produce acceptable morbidity and recurrence rates. Methods: Patients with rectal cancer 4 to 8 cm from the dentate line underwent laparoscopically-assisted transsacral resection (LTR) with primary anastomosis. With this technique, the rectosigmoid is mobilized via laparoscopy while the patient is in the supine position. Next, the patient is placed in the prone jackknife position, and a segment of rectum is resected by a transsacral approach. Age, estimated blood loss, length of time in the operating room, length of stay, and postoperative complications were noted. Aspects of the tumor pathology regarding stage, lymph nodes, tumor size, and presence of tumor at resection margins also were recorded. Results: A total of 13 patients, ages 26 to 70 years (mean, 52.5 years), underwent the procedure. No perioperative deaths occurred. The mean hospital stay was 9.6 days. The average size of the rectal lesion was 4.3 cm in the largest dimension. The average specimen contained 11.5 total, and 2.0 metastatic lymph nodes. Postoperative complications included two anastomotic breakdowns and two other wound complications. Late follow-up evaluation ranged from 10 to 30 months, with 11 of 13 patients alive (85% survival). Two local recurrences and three distant recurrences were noted at long-term follow-up assessment. Conclusions: In selected patients with low or midlevel rectal cancer, LTR may be a viable option. Further experience is necessary to define its oncologic efficacy and whether routine temporary diverting colostomy is indicated. Received: 16 June 1999/Accepted: 1 November 1999/Online publication: 12 July 2000     

Accuracy of endorectal ultrasonography in staging locally advanced rectal cancer after preoperative chemoradiation

Aim  The aim of our study was to determine the accuracy of endorectal ultrasonography (ERUS) in staging locally advanced rectal cancer after preoperative neoadjuvant chemoradiation and to point out the most common reasons for false interpretation. Methods  Forty-four patients with locally advanced rectal cancer received neoadjuvant chemoradiation followed by radical surgery. Restaging was done 1–2 weeks before surgery and the results of ERUS staging were compared with histopathology findings of the resected specimen. Results  The accuracy of ERUS for T stage after chemoradiation was 75% (33/44). Overstaging occurred in 18% (8/44) of patients, and 7% (3/44) were understaged. The majority of overstaging occurred in patients with ERUS T3 tumors, eventually found to have pathological pT0–pT2 staging. Five patients (11.4%) had complete histology regression and only one of these patients was staged correctly while others were overstaged. In the detection of perirectal lymph node metastases, ERUS was accurate in 68% of patients (30/44). Twenty percent (9/44) of patients were overstaged and 11% were (5/44) understaged. Conclusions  ERUS provides a good accuracy rate for staging rectal cancer after neoadjuvant chemoradiation. However, it is insuficient in detection of complete pathological response.     

A prospective comparison of laparoscopic ultrasound vs intraoperative cholangiogram during laparoscopic cholecystectomy

Background: The laparoscopic ultrasound (US) probe provides a new modality for evaluating biliary anatomy during laparoscopic cholecystectomy (LC). Methods: We performed a laparoscopic US examination in 65 patients without suspected common bile duct (CBD) stones prior to the performance of a laparoscopic cholangiogram (IOC). We then compared the cost, time required, surgeon's assessment of difficulty, and interpretations of findings. Results: There was a significant difference in the cost of US versus the cost of IOC ($362 ± 12 versus $665 ± 12; p < 0.05). Surgeons who had performed >10 US (EXP) were compared with those who had performed ≤10 (NOV). There were significant differences between the EXP and NOV groups in ease of examination, visualization of biliary anatomy, and accuracy of measurement of the CBD. Conclusions: The use of laparoscopic US for the accurate evaluation of the CBD and biliary anatomy requires that the surgeon has surpassed the learning curve, which we have defined as having performed >10 US exams. Received: 1 May 1998/Accepted: 21 October 1998     

Endothoracic sonography with color Doppler availability during video assisted thoracic surgery (videothoracoscopic operative staging with ultrasound color Doppler) for lung cancer staging

Background: The preoperative staging of lung cancer can be problematical when we attempt to evaluate T factor (T2–T3 versus T4) and N factor (N0 versus N1–N2). In some cases, radiology tests (CT scan, magnetic resonance imaging) cannot entirely dispel the possibility that the mediastinal structures have been infiltrated. N factor is evaluated mainly by dimensional criteria. However, mediastinoscopy and mediastinotomy do not allow the full exploration of all mediastinal mode stations. Method: Starting in 1995, we submitted 10 consecutive patients to videothoracoscopic operative staging with ultrasound color Doppler (VOS-USCD). In five cases, preoperative staging showed possible infiltration of the pulmonary artery (T4). In nine cases, we found involvement of the mediastinal nodes, seven patients were N2, and two were N3. Videothoracoscopy was performed under general anesthesia using a double-lumen endotracheal tube. The videothoracoscope and sonographic probe were inserted via three thoracoports placed in the axillary triangle. Results: Following the results of VOS-USCD, the staging and subsequently the therapeutic program were modified in seven of 10 cases (70%). Conclusions: Our preliminary experience indicates that VOS-USCD should be applied to the diagnosis of patients in stage IIIA (N2) and that it is particularly valuable for patients in stage IIIB. Received: 23 May 1997/Accepted: 28 October 1997     

Endorectal ultrasound detection of focal carcinoma within rectal adenomas

BACKGROUND: 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: "biopsy-negative 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.