Prospective comparison of endorectal ultrasound, three-dimensional endorectal ultrasound, and endorectal MRI in the preoperative evaluation of rectal tumorsrid=""

Background: The aim of this study was to compare the value of endorectal ultrasound (EUS), three-dimensional (3D) EUS, and endorectal MRI in the preoperative staging of rectal neoplasms. Methods: Thirty consecutive patients with rectal tumors were assessed by EUS and endorectal MRI. Additionally, three-dimensional ultrasound was performed in a subgroup of 25 patients. EUS data were obtained with a bifocal multiplane transducer (10 MHz) and processed on a 3D ultrasound workstation. MR imaging was carried out with a 1.5 T superconducting unit using an endorectal surface coil. Results: EUS was carried out successfully in all 30 patients, whereas endorectal MRI was not feasible in two patients. Compared with the histopathological classification, EUS and endorectal MRI correctly determined the tumor infiltration depth in 25 of 30 and 28 patients, respectively. The comparative accuracy of EUS, 3D EUS, and endorectal MRI in predicting tumor invasion was 84%, 88%, and 91%, respectively. EUS, three-dimensional EUS, and endorectal MRI enabled us to assess the lymph node status correctly in 25, 25, and 24 patients, respectively. Both three-dimensional EUS and endorectal MRI combined high-resolution imaging and multiplanar display options. Assessment of additional scan planes facilitated the interpretation of the findings and improved the understanding of the three-dimensional anatomy. Conclusion: The accuracy of three-dimensional EUS and endorectal MRI in the assessment of the infiltration depth of rectal cancer is comparable to conventional EUS. One advantage of both methods is the ability to obtain multiplanar images, which may be helpful for the planning of surgery in the future. Received: 4 April 2000/Accepted: 25 August 2000/Online publication: 27 October 2000     

Endosonographic examination of gastrointestinal anastomoses with suspected locoregional tumor recurrence

Background: Endoscopic ultrasound is considered one of the best tools for the preoperative staging of esophageal, gastric, and rectal carcinoma. Depending on the individual investigator, the sensitivity of preoperative tumor staging by endosonography of the upper gastrointestinal tract (GEUS) is 80–92% for gastric carcinoma and 86–95% for esophageal carcinoma. However, the sensitivity and specificity of endosonography for the staging of lymph node metastases is less accurate. The accuracy of rectal endosonography (REUS) is ∼90% for tumor assessment and ∼80% for the detection of lymph node metastases. In this study, we address the question of whether endosonography enables the surgeon to distinguish scar tissue, which is rather homogeneous and echo-rich, from changes such as an anastomositis or a locoregional tumor recurrence, which are typically noninhomogeneous and echo-poor. Methods: During a 24-months period, we studied patients enrolled in a special tumor follow-up care program by either upper gastrointestinal (GEUS, n= 37 patients) or rectal endosonography (REUS, n= 49 patients) for exclusion of a locoregional tumor recurrence. In each patient, local tumor recurrence was suspected because of either medical history, clinical examination, or other diagnostic procedures. Results: As in previous studies, our retrospective analysis revealed that endosonography has a high sensitivity in the detection of local tumor recurrences (>90%) for both GEUS and REUS. Conclusion: Endosonography is a highly accurate means of detecting local tumor recurrence. Received: 9 March 1998/Accepted: 9 November 1998     

Is laparoscopic sonography a reliable and sensitive procedure for staging colorectal cancer?

Background: Laparoscopic colectomy has developed rapidly with the explosion of technology. In most cases, laparoscopic resection is performed for colorectal cancer. Intraoperative staging during laparoscopic procedure is limited. Laparoscopic ultrasonography (LUS) represents the only real alternative to manual palpation during laparoscopic surgery. Methods: We evaluated the diagnostic accuracy of LUS in comparison with preoperative staging and laparoscopy in 33 patients with colorectal cancer. Preoperative staging included abdominal US, CT, and endoscopic US (for rectal cancer). Laparoscopy and LUS were performed in all cases. Pre- and intraoperative staging were related to definitive histology. Staging was done according to the TNM classification. Results: LUS obtained good results in the evaluation of hepatic metastases, with a sensitivity of 100% versus 62.5% and 75% by preoperative diagnostic means and laparoscopy, respectively. Nodal metastases were diagnosed with a sensitivity of 94% versus 18% with preoperative staging and 6% with laparoscopy, but the method had a low specificity (53%). The therapeutic program was changed thanks to laparoscopy and LUS in 11 cases (33%). In four cases (12%), the planned therapeutic approach was changed after LUS alone. Conclusions: The results obtained in this study demonstrate that LUS is an accurate and highly sensitive procedure in staging colorectal cancer, providing a useful and reliable diagnostic tool complementary to laparoscopy. Received: 2 May 1997/Accepted: 11 February 1998     

The role of staging laparoscopy for multimodal therapy of gastrointestinal cancer

Background: This prospective study was conducted to evaluate the accuracy and the therapeutic relevance of staging laparoscopy. Methods: Between June 1993 and February 1997 staging laparoscopy was performed in 389 patients with various neoplasms. Additionally, 144 selected patients of this group were examined with laparoscopic ultrasound using a semiflexible ultrasound probe (7.5 MHz). Results: Compared to conventional imaging methods, laparoscopy and laparoscopic ultrasound improved the accuracy of staging in 158 of 389 patients (41%). Statistical subgroup analysis of 131 patients with gastric cancer showed that the accuracy of staging laparoscopy in the detection of distant metastases (68%) was significantly higher (p < 0.01) than that of ultrasound (63%) or computed tomography (58%). In the whole group, laparoscopy alone disclosed intraabdominal tumor dissemination or nonresectable disease in 111 patients. Laparoscopic ultrasound displayed additional metastases—i.e., liver metastases (n = 9), M1 lymph nodes (n = 15), or nonresectable tumors (n = 6) in 30 patients. Although metastastic disease was suggested by preoperative imaging, benign lesions were found in five patients with laparoscopy and in a further 12 patients with ultrasonography. The findings of staging laparoscopy changed the treatment strategy in 45% of the patients. Conversion to open surgery was necessary in 5% of the cases, and complications related to laparoscopy occured in 4% of the patients. Conclusions: Laparoscopy with laparoscopic ultrasound improves the staging of gastrointestinal tumors and has a significant impact on a stage-adapted surgical therapy. Received: 3 April 1997/Accepted: 26 September 1997     

Preoperative chemoradiation in patients with resectable rectal cancer: Results on tumor response

Background There is no consensus about the role of preoperative radiotherapy (RT) and chemotherapy (CT) in patients with resectable cancer of the distal rectum. This study analyzed the local clinical and pathologic response in patients receiving preoperative RT/CT for rectal cancer. Methods Thirty-two consecutive patients with a palpable adenocarcinoma of the rectum received preoperative RT (45 Gy in 25 fractions over 5 weeks), plus continuous chemotherapy with doxifluridine and leucovorin or 5-fluorouracil by continuous intravenous infusion during RT. Surgery was performed 8 weeks later. The Wilcoxon andχ ² tests were used for data analysis. Results Twelve patients had mild gastrointestinal toxicity, only one of whom required interruption of therapy. The tumor shrank to 57.8% of its original size, and at the echoendoscopy (u) there was a 58.7% decrease of the maximum diameter (P<.001). Downstaging from uT3 and uT2 to <uT3 and <uT2, respectively, occurred in 41.6% of patients (P=.0020). Total and major regression of the tumor at the histopathologic examination occurred in 12.5% and 50% of patients. Conclusions Local response to preoperative RT/CT was highly satisfactory and allowed conservative surgery in 81% of patients. Optimization of the combined therapy could achieve even better results.     

T4-Rektumkarzinom Operative und multimodale Therapie

BACKGROUND: In locally advanced rectal cancer with infiltration of neighbouring organs (uT4), resectability and local control are difficult to achieve. Combined preoperative radiochemotherapy may result in increased resectability and reduced local recurrence rates. PATIENTS AND METHODS: Thirty-four patients with biopsy-proven locally advanced rectal cancer were treated by preoperative radiochemotherapy. All tumours had been staged as uT4 lesions by endorectal ultrasound or computed tomography. Radiotherapy was applied in standard blocks, 5 x 1.8 Gy up to 45 Gy. Chemotherapy consisted of two cycles of 5-fluorouracil (300-350 mg/m2/day) and leucovorin (50 mg). In 20 patients, additional thermotherapy was carried out using the Sigma 60 applicator BSD 2000 once a week prior to radiotherapy. Surgery was performed 4-6 weeks after radiochemotherapy. Postoperatively, all patients received four cycles of 5-fluorouracil and leucovorin. RESULTS: Treatment-induced toxicity occurred in 26% of the patients (WHO grade III (n = 6) and IV (n = 3)). The resectability rate was 76% (26/34 patients) (R0 resectability n = 21; 62%). The pathological complete response rate was 6% (n = 2) and the partial response rate was 47% (n = 16). A local failure was observed in six patients after median time of 16 months (range 7-36 months). Patients with R0 resection achieved a 5-year disease-free survival rate of 55% and a survival rate of 71%. The overall 5-year survival rate for all patients with advanced uT4 rectal cancer was 49%. CONCLUSIONS: Our data on preoperative combined treatment in locally advanced T4 rectal cancer revealed encouraging downstaging, local control, and survival rates.     

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     

Preoperative tumour staging with multidisciplinary team assessment improves the outcome in locally advanced primary rectal cancer

Aim Multidisciplinary team meetings have been introduced as a result of developments in preoperative radiological tumour staging and neoadjuvant treatment. Multidisciplinary team recommendations will influence treatment decisions but their effect on patient outcome is unknown. The aim of this study was to assess outcome in relation to preoperative local and distant staging, with or without multidisciplinary team assessment. Methods A population‐based registry of all patients with rectal cancer, treated in the Stockholm region from 1995 to 2004, identified 303 patients with locally advanced primary rectal cancer. The patients were classified into three groups: group 1, preoperative local and distant radiological tumour staging with discussion at a multidisciplinary team meeting; group 2, preoperative staging but no multidisciplinary team assessment; and group 3, no proper preoperative radiological staging. Results Neoadjuvant treatment was more prevalent in groups 1 and 2 than in group 3. The incidence of R0 resection differed significantly between the groups (52% in group 1, 43% in group 2 and 21% in group 3; P < 0.001). Local tumour control was achieved in 57%, 36%, and 19% of patients in groups 1, 2 and 3, respectively (P < 0.001). The estimated overall 5‐year survival of patients was 30%, 28% and 12% in groups 1, 2 and 3, respectively. Conclusion Preoperative radiological tumour staging in patients with locally advanced primary rectal cancer and discussion at a multidisciplinary team meeting increases the proportion of patients receiving neoadjuvant treatment and cancer‐specific end‐points.     

TNM staging and assessment of resectability of pancreatic cancer by laparoscopic ultrasonography

Background: Laparoscopic ultrasonography (LUS) is an imaging modality that combines laparoscopy and ultrasonography. The purpose of this prospective blinded study was to evaluate the TNM stage and assessment of resectability by LUS in patients with pancreatic cancer. Methods: Of the 71 consecutive patients admitted to our department, 36 were excluded from the study, mainly due to evident signs of metastatic disease or another condition that would preclude surgery. Thus, a total of 35 patients were enrolled in the study. All patients underwent abdominal CT scan, ultrasonography, endoscopic ultrasonography (EUS), diagnostic laparoscopy, and LUS. Histopathologic examination was considered to be the final evaluation for LUS in all but three patients, where EUS was used as the reference. Results: The accuracy of LUS in T staging was 29/33 (80%); in N staging it was 22/34 (76%); in M staging, it was 23/34 (68%); and in overall TNM staging, it was 23/34 (68%). In assessment of nonresectability, distant metastases, and lymph node metastases, the sensitivity was 0.86, 0.43 and 0.67, respectively, for LUS alone. Combining the information gleaned from laparoscopy and LUS, the accuracy in finding nonresectable tumors was 89%. Conclusions: Diagnostic laparoscopy with LUS is highly accurate in TNM staging and assessment of resectability of pancreatic cancer and should be considered an important modality in the assessment algorithm. Received: 6 July 1998/Accepted: 13 October 1998     

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     

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     

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     

Do MRI Reports Contain Adequate Preoperative Staging Information for End Users to Make Appropriate Treatment Decisions for Rectal Cancer?

Purpose

This study was designed to elicit end-user opinions regarding the importance and diagnostic accuracy of MRI for T-category, threatened or involved circumferential margin (CRMi), and lymph node involvement (LNi) for preoperative staging of rectal cancer and to determine completeness of MRI reports for these elements on a population based level.

Methods

The first part of this study was a mailed survey of surgeons, radiation oncologists, and medical oncologists to elicit their opinions regarding the importance and diagnostic accuracy of T-category, CRMi, and LNi on MRI. The second part of the study was an audit of MRI reports issued for pre-operative staging of rectal cancer to assess the completeness of these reports for T-category, CRMi, and LNi.

Results

Although T-category, CRMi, and LNi were considered essential by 97, 94, and 77 % of respondents, respectively, the MRI report audit showed that only 40 % of MRI reports captured all of these elements. The majority of end users reported moderate diagnostic accuracy on MRI for T-category and CRMi and low diagnostic accuracy for LNi (52.3, 43, and 48.5 % respectively). Multivariate analysis showed that specialty was the only independent predictor of correct reporting of the diagnostic accuracy for each of the MRI elements.

Conclusions

While end users consider T-category, CRMi and LNi essential for preoperative staging of rectal cancer, less than 40 % of MRI reports captured all of these elements. Therefore, strategies to improve communication between radiologists and end users are critical to improve the overall quality of care for rectal cancer patients.     

Selektion von Patienten mit Rektumtumoren zur lokalen Exzision aufgrund der präoperativen Diagnostik

INTRODUCTION: The aim of our study was to evaluate the accuracy of clinical staging (CS), biopsies, and endoluminal ultrasonic examination (EUS) in preoperative staging of rectal tumors treated with transanal local excision. This local excision is an adequate procedure for benign rectal polyps and low-risk T1 carcinoma. PATIENTS AND METHODS: The study included 552 patients with rectal adenocarcinoma, villous adenoma, or tumors with other histologic characteristics who underwent a transanal excision (transanal endoscopic microsurgery n=513 or transanal excision n=39). We compared the results of CS, biopsies, and EUS with postoperative pathology findings. RESULTS: Preoperative histological diagnosis of the rectal carcinoma depended on tumor size (52% in cancers <3 cm, 25% in cancers >3 cm; p=0.001) and was correct in 56% of cases. Transanal ultrasonography (uT0/1) had superior sensitivity (95% vs 78%) and a higher positive predictive value (93% vs 85%) than clinical staging (CS I) in detecting adenoma or T1 rectal carcinoma, whereas specificity was similar in both (62% vs 58%). In patients in whom preoperative histological analysis revealed adenomas, transanal ultrasonography was accurate (uT0/1) for the postoperatively assessed adenoma pT1 in 97%, whereas diagnosis (uT0/1) was correct in only 71% of cases in which preoperative histological analyses showed rectal carcinomas. CONCLUSIONS: In patients with rectal tumors, preoperative staging with transanal ultrasonography and biopsy is essential for the indication and allows selection of patients for transanal local excision.     

Preoperative staging of patients with rectal tumors suitable for transanal endoscopic microsurgery (TEM): comparison of endorectal ultrasound and histopathologic findings

Background  Accurate preoperative staging is the key to correct selection of rectal tumors for local excision. This study aims to assess the accuracy of endorectal ultrasound (ERUS) at our institution. Patients and methods  Retrospective analysis was carried out of patients treated by transanal endoscopic microsurgery (TEM) from 1996 to 2008. TEM was considered the treatment of choice for uT0-1/N0 lesions located between 2 and 12 cm from the anal verge. It was also proposed in selected uT2-3 patients. Preoperative staging was compared with histopathologic findings. Results  Eighty-one patients (46 males, mean age 66 years) underwent TEM. Mean distance of the tumor from the anal verge was 6.6 cm (range 2–12 cm). ERUS staged 15 of 27 adenomas (55%) as uT1. Of 54 carcinomas, 5 were pT0 because TEM was performed to remove resection margins of a malign polyp already snared. Five of 19 pTis (26%) were overstaged uT1, while 7 of 17 pT1 (41%) were understaged. Overall, ERUS enabled distinction between early and advanced rectal lesion with 96% sensitivity and 85% specificity, giving accuracy of 94% (65/67). Thirteen patients had advanced lesions (eight pT2 and five pT3). Only in two of them (15%) was depth of invasion underestimated by ERUS (one uT0, one uT1) and thus was subsequent salvage surgery necessary. Conclusions  ERUS is useful to confirm the diagnosis of adenoma and predict depth of mural invasion in early rectal cancer. Differentiation between T0/is and T1 lesions remains challenging, however this does not usually influence surgical strategy.     

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.     

Video-laparoscopic staging of gastric cancer

Background: The high proportion of gastric carcinomas present in an unresectable stage, together with the emergence of multimodal treatments, increases the usefulness of objective staging methods that avoid unnecessary laparotomies. Methods: A prospective evaluation of the accuracy of laparoscopy in the staging of 71 patients with gastric adenocarcinoma is presented. Serosal infiltration, retroperitoneal fixation, metastasis to lymph nodes, peritoneal and liver metastasis, and ascites were determined in the staging workup. Sensitivity, specificity, and predictive values were calculated and compared with those obtained with ultrasonography (US) and computed tomography (CT). Results: The diagnostic accuracy of laparoscopy in the determination of resectability was 98.6%. Consequently, over 40% of patients were spared unnecessary laparotomies. Laparoscopy yielded diagnostic indices superior to US and CT for all the tumoral attributes studied. Our technique permits accurate assessment and pathologic verification of liver and the peritoneal and retroperitoneal extent of tumor invasion in the majority of patients. Conclusions: Laparoscopy in gastric adenocarcinoma is a reliable technique that provides accurate assessment of resectability and stage, thus avoiding unnecessary laparotomies in patients in whom surgical palliation is not indicated. A stepwise diagnostic workup combining imaging and minimally invasive techniques is proposed. Received: 5 May 1996/Accepted: 10 March 1997     

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     

Application of rectal stents for palliation of obstructing rectosigmoid cancer

Background: The rationale of palliative endoscopic treatment is to avoid a colostomy in patients with advanced disease and limited life expectancy. This study was conducted to evaluate the role of endoscopic stent implantation for palliation of obstructing rectal cancer. Methods: Overall, 19 patients (aged 47–87 years) with nonresectable or metastatic rectal cancer were treated by stent insertion after laser recanalization or dilation. Three types of stents, i.e., plastic tubes (n= 8), self-expanding mesh stents (n= 6), and endocoil stents (n= 5), were used to maintain luminal patency. Results: Endoscopic stent implantation was successfully performed in all 19 patients. Long-term luminal patency and satisfactory bowel function were achieved in 16 of 19 patients (84%). After a median follow-up of 6 months, eight of the patients have died and eight are still alive without evidence of recurrent obstruction. Dislocation of the endoprosthesis occurred in two of eight plastic tubes and one of five mesh stents. Recurrent obstruction due to tumor ingrowth was only observed in patients treated with self-expanding mesh stents (n= 2). In spite of reinsertion and laser therapy a colostomy was required in three of 19 patients. There was no evidence of treatment failure in five patients who received endocoil stents. None of the patients experienced serious complications related to the endoscopic procedure. Conclusions: Endoscopic stent implantation seems to be a safe and efficient palliative approach to selected patients with obstructing rectal cancer. Currently, self-expanding coil stents are superior to other devices because of lower risk of dislocation and tumor ingrowth. Received: 10 May 1996/Accepted: 11 November 1996     

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

Introduction. Neoadjuvant radiochemotherapy (neoRT/CT) in locally advanced rectal cancer requires an exact initial determination of the depth of the cancerous infiltration (T-status) and of locoregional lymph node metastasis (N-status).For staging and restaging, contrastenhanced computed tomography (CT) is usually used. In specialised centers, the endorectal ultrasound (rES) may be preferred. Methods. Between January 1998 and May 2001, the T- and N-status of 102 patients with adenocarcinoma of the rectum (≥T3 or N+) was determined prospectively by rES and CT (group I: n=61 without neo-RT/CT, examined once; group II: n=41 examined before and after neoRT/CT). All diagnostic findings were compared using the (y)pTNMclassification. Results. In the patients from group I, the depth of infiltration (uT) was predicted correctly by rES in 75% and by CT in 48% of cases; the carcinomas were understaged in 10% and 41% of cases and overstaged in 15% and 11%, respectively.According to the histopathological findings, the N-status was determined correctly by rES and CT in 75% and 57% of cases, understaging occurred in 8% and 30% and overstaging in 17% and 13%, respectively. In cases in which both methods resulted in identical T- (uT+ctT) or N-staging (uN+ctN), the accuracy increased to 82% and 80%, respectively. In patients from group II, after neoRT/CT rES and CT allowed the exact prediction of the yuT-stage in 66% and 51%, respectively.Only 2% were understaged by rES (understaging by CT: 22%).Overstaging occurred in 32% and 27% by rES and CT, respectively.The N-status determined by rES and CT was in accordance with the histopathological findings in 68% and 76%of cases, respectively. Understaging occurred in 20% and 17%,overstaging in 12% and 7%, respectively.Again identical staging results in both rES and CT increased the accuracy of the T- (yuT+yctT) or N- (yuN+yctN) classification to 90% and 83%, respectively. In group II, downsizing of the tumor by more than one T-stage was correctly assessed by rES results in 15/20cases (75%). A complete remission of initial uT3-carcinoma was diagnosed correctly in only two of eight ypT0-cases. In contrast, CT demonstrated a remission of disease in all cases but was unable to predict the extent of tumour reduction. A remission of lymph node metastasis was accurately shown by rES in 17/19 cases (90%) and by CT in 10/12 cases (83%). Conclusion. The staging of pretherapeutic, locoregional T- and N-status by rES is superior to that by CT (T-status: P=0.0164, N-status: P=0.0035).At restaging, rES offers higher accuracy in the detection of residual tumour infiltration (but not significantly to CT, yT-status: P=0.0833, yN-status: P=0.7962) and assessment of local remission. Therefore rES should be the method of choice in staging to avoid overtreatment in neoadjuvant settings.After neoRT/CT, the predictive efficacy of the rES for the downsizing/-staging of rectal cancer must be evaluated on greater numbers of patients receiving standardised diagnostic procedures and therapy.