Problems in the colonoscopic localization of tumors: continued value of the barium enema

The Accuracy of Different Modalities Used for Preoperative Primary Tumour Localisation in Operated Colorectal Cancer Patients

Aim Colonoscopy and computed tomography (CT) scans of the abdomen and pelvis are routine pre-operative assessment tools in colorectal cancer (CRC) patients. There have been some discrepancies regarding the location of cancer when seen by colonoscopy versus CT scan. The purpose of this study was to compare the accuracy of a colonoscopy with a computed tomography (CT) scan of the abdomen and pelvis with contrast, which is done routinely before surgery to localise the exact site of the tumour within the large bowel, whilst comparing both to the operative, gross and histopathology findings of the exact location. Methods A retrospective study was carried out on 165 colorectal cancer patients operated on between January 1, 2010, and December 31, 2014, using electronic hospital records that were reviewed anonymously, comparing the location of cancer within the large bowels as was found on colonoscopy and CT scan of the abdomen and pelvis with contrast, comparing both to post-operative histopathology specimen or intra-operative assessment in cases where no resection of the primary tumour was performed. Results CT and colonoscopy were both accurate in diagnosing 70.5% of cases that had done both investigations pre-operatively. The best results were obtained when the cancer was located in the caecum as confirmed post-operatively; the combined accuracy rate was 100%. CT was accurate, whilst colonoscopy was not in eight (6.2%) cases (all are rectal or sigmoid cancers), and colonoscopy was accurate and CT was not in 12 cases, 10 of them were rectal and two were ascending colonic. Colonoscopy was not performed in 36 (21%) cases for a variety of reasons, including large bowel obstruction or perforation on presentation. In 32 of these cases, CT scan managed to accurately predict the location of cancer (mostly rectal and caecal), and CT scan was inaccurate in 20.6% of cases (34 out of 165), whilst colonoscopy was inaccurate in 13.9% of cases (18 out of 129). Conclusion Colonoscopy is more accurate in localising colorectal cancers than CT scan of the abdomen and pelvis with contrast. CT scan diagnoses regional and distant spread of colorectal cancers such as nodal status, invasion of neighbouring organs and/or peritoneum and the presence of liver metastases, whilst colonoscopy is limited to intraluminal diagnosis but can be both a diagnostic and therapeutic tool, with higher accuracy, in general, in localising colorectal cancers. Both CT scan and colonoscopy were equal in appendicular, caecal, splenic flexure and descending colon cancer localisation accuracy.

Assessing the Association Between Endoscopic Tattooing and Lymph Node Yield in Rectal Cancer

INTRODUCTION

Preoperative endoscopic tattooing is an effective tool for intraoperative tumor localization in colon cancer. Endoscopic tattooing in rectal cancer may have unidentified benefits on lymph node yield, making it easier for pathologists to identify nodes during histopathologic assessment. There remains concern that tattoo ink may alter anatomical planes, increasing surgical difficulty.

METHODS

Retrospective chart reviews from 2016 to 2021 of n = 170 patients presenting with rectal cancer were divided into two groups: with (n = 79) and without (n = 91) endoscopic tattoos. Demographics, operative details, tumor characteristics, prior chemoradiation, and pathologic details were collected. Primary outcome was total lymph node yield. Secondary outcomes were rates of adequate (> 12) nodes, margin status, and operative variables including operative time.

RESULTS

No differences between pathologic stage, tumor height, high inferior mesenteric artery ligation, operative times, conversion rate, or surgical approach (open versus minimally invasive) were noted between groups. Receipt of neoadjuvant chemoradiation was less frequent in the endoscopic tattooing group (53.2% versus 76.9%, P ≤ 0.001). Total node number and rate of adequate lymph node yield were higher with endoscopic tattooing (20.5 ± 7.6 versus 16.8 ± 6.6 lymph nodes and 100.0% versus 83.5% adequate lymph node harvest, both P ≤ 0.001). Rates of positive circumferential and distal margins and complete total mesorectal excision were also similar. Regression analysis identified endoscopic tattooing (Incidence Risk Ratio 1.17, 95% confidence interval 1.04-1.31) and operative time more than 300 min (Incidence Risk Ratio 0.88, 95% confidence interval 0.77-0.99) had significant effects on lymph node harvest. Removal of patients with inadequate lymph node yield resulted in similar rates of total and positive lymph nodes.

CONCLUSIONS

Endoscopic rectal tattooing is associated with increased lymph node yield (including after neoadjuvant chemoradiotherapy) without sacrificing oncologic or perioperative outcomes, although this effect is inconsistent when only considering patients with an adequate lymph node yield.

Inking outside the box: systematic review on the utility of tattooing lesions in rectal cancer

PURPOSE

Endoscopic tattooing in rectal cancer is infrequently utilized for fear of tattoo ink obscuring anatomical planes, increasing the difficulty of surgical excision. Colon cancer tattooing has demonstrated increased lymph node yields and increased accuracy in establishing adequate margins. Rectal cancer tattooing may be especially helpful after neoadjuvant chemoradiation, where complete clinical responses could limit lesion identification and lymph node yields are typically less robust. We seek to review and identify the effects of tattooing in rectal cancer.

METHODS

A systematic literature search was performed in PubMed, Embase, and SCOPUS. Studies on endoscopic tattooing with cohorts consisting of at least ≥ 25% of rectal cancer patients were selected. Studies focusing solely on rectal cancer were also reviewed separately.

RESULTS

Of 416 studies identified, 10 studies encompassing 2460 patients were evaluated. Seven studies evaluated lymph node yields; five reported beneficial effects of endoscopic tattooing, while two reported no significant difference. Among four studies reporting lesion localization, successful localization rates were between 63 and 100%. Rates of intraoperative endoscopy performed to reevaluate lesion location ranged from 5.7 to 20%. The distal margin was evaluated in two studies, which reported more accurate placement of the distal resection margin after tattooing. When complications of tattooing were documented (7 studies with 889 patients), only five direct complications of endoscopic tattooing were observed (0.6%).

CONCLUSIONS

Although the data is heterogenous, it suggests that endoscopic tattooing in rectal cancer may improve lymph node yields and assist in determining accurate distal margins without high rates of complication. Further research must be completed before practice management guidelines can change.

TRIAL REGISTRATION

No. CRD42021271784.

Computed tomographic colonography versus double-contrast barium enema for the preoperative evaluation of rectal cancer

PURPOSE

We investigated whether or not computed tomographic colonography (CTC) is a viable alternative to double-contrast barium enema (BE) for a preoperative rectal cancer evaluation.

METHODS

The size and distance from the anal canal to the lower or upper tumor borders were laterally measured in 147 patients who underwent CTC and BE. Measurements were grouped into early cancer, advanced, and after chemoradiation therapy (CRT).

RESULTS

In the early and advanced cancer groups, all lesions were visualized by BE. In contrast, 3 (7.8%) early and 8 (7.3%) advanced cases, located at the anterior wall near the anal canal, were not visualized by CTC because of liquid level formation. In the CRT group, 16 (23.5%) and 4 (5.8%) cases were not visualized by CTC and BE, respectively. The BE and CTC size measurements were similar among cohorts. However, the distance from the anal canal's superior margin tended to be longer with BE, especially in early cancer. The differences in distance from the anal canal were significantly larger in the early cancer group than in the other two groups (p = 0.0024).

CONCLUSION

CTC may be a viable alternative imaging modality in some cases. However, BE should be employed in anterior wall cases near the anal canal and CRT cases.

The Usefulness of Preoperative Colonoscopic Tattooing with Autologous Blood for Localization in Laparoscopic Colorectal Surgery

Purpose

In colorectal cancer surgery, it is important to have accurate resection margins. However, it is challenging to localize lesions during laparoscopy. Therefore, to reduce surgical errors, many preoperative localizing methods have been introduced. In this study, we aimed to assess the preoperative feasibility and safety of autologous blood tattooing.

Methods

A total of 11 patients underwent preoperative colonoscopic autologous blood tattooing from August 2017 to February 2020. At the start of the surgery, the surgeon assessed the patients for the precision of visibility and other complications such as abscess or spillage. The patients’ characteristics, outcomes, and complications were collected retrospectively.

Results

The study comprised 8 men and 3 women, with an average age of 63 years. Ten patients showed precise visibility, and no localization errors were observed during surgery. No complication was observed in all patients.

Conclusion

Preoperative autologous blood tattooing is a very useful and safe technique because it has high visibility with no complications. This method does not require additional agents or facilities. A large-scale study will be required to develop standard guidelines.

Indocyanine green-loaded injectable alginate hydrogel as a marker for precision cancer surgery

Background

Accurate identification of tumor sites and boundaries is of paramount importance during minimally invasive surgery. Although laparoscopic resection is being increasingly and widely performed for early gastric and colorectal cancers, the detection of tumors located inside the stomach and intestine is difficult owing to the lack of tactile sensation. Here, we propose the application of an indocyanine green (ICG)-loaded alginate hydrogel system as a fluorescence surgical marker for precise laparoscopic operations.

Methods

A physical complex of ICG and human serum albumin (HSA) was mixed with sodium alginate to form an injectable hydrogel system. Calcium carbonate and D-gluconic acid (GA) were added to the gel to control its strength and gelation time, respectively. The optimal conditions for the preparation of injectable hydrogels were determined by analyzing the fluorescence spectra and sol-gel transition time of the prepared samples at various concentrations and compositions. Next, the aqueous solutions of ICG, ICG-HSA, and ICG-HSA-loaded alginate were subcutaneously injected into nude mice (three mice per group), and near-infrared (NIR) fluorescence images of the mice (λ_ex. =780 nm, λ_em. =845 nm) were obtained at different points in time for 8 days. Then, fluorescence intensities at the injection sites, target-to-background ratio, and areas of ICG fluorescence were analyzed. Finally, the potential utility of ICG-HSA-loaded alginate hydrogel as a surgical marker was evaluated in a porcine model. The ICG-HSA-loaded alginate solution was injected into three sites in the submucosal space of the porcine stomach via a catheter. A fluorescent laparoscopic system was installed on the abdomen of the pig 3 days post-injection, and the fluorescence signal generated from the fluorescence surgical marker located inside the stomach was evaluated using the fluorescence laparoscope system (λ_ex. =785 nm, λ_em. =805 nm).

Results

The optimal concentration of ICG-HSA complex was determined to be 30 µM, and maximum fluorescence intensity of the complex was obtained at a 1:1 mole ratio of HSA to ICG. The subcutaneous injection of ICG or ICG-HSA solution in mice resulted in the rapid spread of the fluorescence signal around the injection site in 3 h, and a weak fluorescence was detected at the injection site 24 h post-injection. In contrast, the fluorescence detection time was effectively prolonged up to 96 h post-injection in the case of ICG-HSA-loaded alginate gel, while diffusion of the injected ICG from the injection site was effectively prevented. In the laparoscopic operation, injection sites of the hydrogel in porcine stomach could be accurately detected in real time even after 3 days.

Conclusions

This alginate hydrogel system may be potentially useful as an effective surgical marker in terms of accuracy and persistence for laparoscopic operation.

Lesion Retrieval, Specimen Handling, and Endoscopic Marking in Colonoscopy

Retrieval of lesions after endoscopic polypectomy enables histopathologic analysis and guides future surgical management and endoscopic surveillance intervals. Various techniques and devices have been described with distinct advantages and disadvantages to accomplish retrieval. Appropriate histopathologic analysis depends on lesion handling and preparation. How lesions are handled further depends on size, endoscopic appearance, and removal technique. Endoscopic marking or tattooing is a well-described process that uses dye mediums to leave longstanding marks in the colon. Techniques, dye mediums, and locations within the colon influence tattoo approach.

"Is CT Scan more Accurate than Endoscopy in Identifying Distance from the Anal Verge for Left Sided Colon Cancer? A Comparative Cohort Analysis"

Purposes: Accurately localizing colorectal cancer during surgery may be challenging due to intraoperative limitations. In the present study, localization of left-sided colon cancer (LCC) by CT scan is compared to colonoscopy. Material and methods: Consecutive patients with LCC located by colonoscopy and CT scan and undergoing left-hemicolectomy were included. Tumor distance from the anal verge (TDAV) was calculated by both CT-scan and colonoscopy, and then compared, using as reference TDAV measured intraoperatively. Statistical analysis was performed including (1) comparison of means between all three TDAVs, (2) comparison of mean differences between all three TDAVs, (3) comparison of number of patients with a difference between endoscopic TDAV and intraoperative TDAV ≤5 cm and the number of patients with a difference between CT scan TDAV and intraoperative TDAV ≤5 cm (4) statistical relationship between either CT scan and endoscopic and intraoperative TDAVs. Results: Both CT scan and endoscopy overestimate TDAV (25.8 ± 12.5 cm and 24.6 ± 10.6 cm vs. 21.5 ± 7.4 cm, p = 0.005), but CT scan TDAV resulted as being different from intraoperative TDAV (p < 0.01). Regression analysis reported an increasing divergence of measurements with increasing values of intraoperative TDAV, which resulted greater for CT. Tumors within 5 cm of intraoperative TDAV were 22/28 (78.6%) for endoscopy, and 17/28 (60.7%) for CT (p = 0.2448). Conclusions: Accuracy of both examinations seems poor, with a mean overestimation >3 cm and a significant number of tumors found at >5 cm from preoperative evaluation. Preoperative examinations' bias increase proportionally with TDAV length, decreasing their interest especially for tumors located at a greater distance from anal verge.

Preoperative Tattooing Using Indocyanine Green in Laparoscopic Colorectal Surgery

Purpose

The aim of the present study was to evaluate the usefulness of indocyanine green (ICG) as a preoperative marking dye for laparoscopic colorectal surgery.

Methods

Between March 2013 and March 2015, 174 patients underwent preoperative colonoscopic tattooing using 1.0 to 1.5 mL of ICG and saline solution before laparoscopic colorectal surgery. Patients’ medical records and operation videos were retrospectively assessed to evaluate the visibility, duration, and adverse effects of tattooing.

Results

The mean age of the patients was 65 years (range, 34–82 years), and 63.2% of the patients were male. The median interval between tattooing and operation was 1.0 day (range, 0–14 days). Tattoos placed within 2 days of surgery were visualized intraoperatively more frequently than those placed at an earlier date (95% vs. 40%, respectively, P < 0.001). For tattoos placed within 2 days before surgery, the visualization rates by tattoo site were 98.6% (134 of 136) from the ascending colon to the sigmoid colon. The visualization rates at the rectosigmoid colon and rectum were 84% (21 of 25) and 81.3% (13 of 16), respectively (P < 0.001). No complications related to preoperative ICG tattooing occurred.

Conclusion

Endoscopic ICG tattooing is more useful for the preoperative localization of colonic lesions than it is for rectal lesions and should be performed within 2 days before laparoscopic surgery.

Accuracy of preoperative tumor localization in large bowel using 3D magnetic endoscopic imaging: randomized clinical trial

Background

Laparoscopic surgery has become the standard treatment for colorectal cancer. A tumor that does not involve serosa is invisible intraoperatively, and manual palpation of the tumor during laparoscopy is not possible. Therefore, accurate localization of the neoplastic infiltrate remains one of the most important tasks prior to elective laparoscopic surgery. The aim of this study was to evaluate the utility of a magnetic endoscopic imaging (MEI) for precise preoperative endoscopic localization of neoplastic infiltrate within the large bowel.

Materials and methods

The study enrolled 246 patients who underwent elective surgery for colorectal cancer in 2012–2015 with accurate preoperative colonoscopic localization of the tumor. The analysis concerned patients with neoplastic infiltrate localized more than 30 cm from the anal verge. For evaluative purposes and accuracy of localization, the intestine was divided anatomically into 13 parts. Colonoscopic examinations were conducted with two types of endoscopes: group I—with MEI and group II—without MEI. Patients were assigned to the groups by random allocation. Ultimate confirmation of the tumor localization was accomplished by intraoperative evaluation.

Results

Group I involved 127 patients and group II 129. The two groups were compared in terms of age, sex, BMI and frequency of previous abdominal procedures. Proper localization of the lesion was confirmed in 95.23 % of group I patients and in 83.19 % of group II patients (p < 0.05). The greatest discrepancy in localization occurred in 8.9 % of patients from group I and 20 % of patients from group II in which the lesion was assessed primarily in the distal sigmoid.

Conclusions

A magnetic endoscopic imaging allows more accurate localization of neoplastic infiltrate within the large intestine compared to standard colonoscopy alone, especially within the sigmoid colon. This method can be particularly useful in planning and performing laparoscopic procedures to diminish the likelihood of improper bowel segment resection.

ClinicalTrials.gov number

NCT01688557

Electronic supplementary material

The online version of this article (doi:10.1007/s00464-016-5203-4) contains supplementary material, which is available to authorized users.

Accuracy of polyp localization at colonoscopy

BACKGROUND AND STUDY AIMS

Accurate documentation of lesion localization at the time of colonoscopic polypectomy is important for future surveillance, management of complications such as delayed bleeding, and for guiding surgical resection. We aimed to assess the accuracy of endoscopic localization of polyps during colonoscopy and examine variables that may influence this accuracy.

PATIENTS AND METHODS

We conducted a prospective observational study in consecutive patients presenting for elective, outpatient colonoscopy. All procedures were performed by Australian certified colonoscopists. The endoscopic location of each polyp was reported by the colonoscopist at the time of resection and prospectively recorded. Magnetic endoscope imaging was used to determine polyp location, and colonoscopists were blinded to this image. Three experienced colonoscopists, blinded to the endoscopist's assessment of polyp location, independently scored the magnetic endoscope images to obtain a reference standard for polyp location (Cronbach alpha 0.98). The accuracy of colonoscopist polyp localization using this reference standard was assessed, and colonoscopist, procedural and patient variables affecting accuracy were evaluated.

RESULTS

A total of 155 patients were enrolled and 282 polyps were resected in 95 patients by 14 colonoscopists. The overall accuracy of polyp localization was 85 % (95 % confidence interval, CI; 60 - 96 %). Accuracy varied significantly (P < 0.001) by colonic segment: caecum 100 %, ascending 77 % (CI;65 - 90), transverse 84 % (CI;75 - 92), descending 56 % (CI;32 - 81), sigmoid 88 % (CI;79 - 97), rectum 96 % (CI;90 - 101). There were significant differences in accuracy between colonoscopists (P < 0.001), and colonoscopist experience was a significant independent predictor of accuracy (OR 3.5, P = 0.028) after adjustment for patient and procedural variables.

CONCLUSIONS

Accuracy of localization of polyps is imprecise and affected by position within the colon and colonoscopist, including their level of experience. Magnetic endoscope imaging may improve the localization of lesions during colonoscopy.

[Colonoscopic Tattooing of Colonic Lesions]

With the development of minimal invasive surgery including laparoscopic and robot surgery, colonoscopic tattooing of colonic lesions is becoming more important to ensure easy localization of the lesion during surgery. Lack of accurate lesion identification during minimal invasive surgery may lead to resection of wrong segment of the bowel. In this article, some topics including proper materials, injection technique, and safety of colonoscopic tattooing are reviewed.

Intraoperative localization of occult colorectal tumors during laparoscopic surgery by magnetic ring markers-a pilot study

PURPOSE

Intraoperative localization of small tumors or malignant polyps has been an important issue in laparoscopic colon surgery. We have developed a new method for preoperative endoscopic tumor marking using a ring-shaped magnetic marker.

METHODS

In a pilot study, 28 patients with small colonic (n = 23) or rectal tumors (n = 5) underwent endoscopic magnetic clipping prior to laparoscopic resection. A cap carrying a high-power neodymium ring magnet was mounted on the tip of a colonoscope. Near the lesion, the ring magnet was released and clipped to the colorectal wall. Standard laparoscopic instruments were used to find the magnet intraoperatively.

RESULTS

Endoscopic fixation of a ring magnet next to the tumor by clipping was technically feasible in all 28 patients. Intraoperative localization of the marked lesions was successful in 27 of 28 patients (96 %). All patients underwent magnet-guided radical laparoscopic resection of the tumor with an average proximal and distal resection margin of 101 and 63 mm, respectively. In one case, the magnet could not be found due to preoperative migration. Surgical complications related to magnetic clip application or intraoperative tumor localization were not observed. However, there was one case with an intraoperative perforation of the colon by the magnet, which was obviously caused by unchecked action with a laparoscopic instrument.

CONCLUSIONS

Preoperative endoscopic labeling of colonic lesions with on-the-scope magnetic markers is simple and safe. Intraoperative tumor localization during laparoscopic colorectal surgery can be achieved reliably without additional equipment such as ultrasound or fluoroscopy.

Endoscopic tattooing

The American Society for Gastrointestinal Endoscopy (ASGE) Technology Committee provides reviews of existing, new, or emerging endoscopic technologies that have an impact on the practice of GI endoscopy. Evidence-based methodology is used, with a MEDLINE literature search to identify pertinent clinical studies on the topic and a MAUDE (U.S. Food and Drug Administration Center for Devices and Radiological Health) database search to identify the reported complications of a given technology. Both are supplemented by accessing the "related articles" feature of PubMed and by scrutinizing pertinent references cited by the identified studies. Controlled clinical trials are emphasized, but in many cases, data from randomized, controlled trials are lacking. In such cases, large case series, preliminary clinical studies, and expert opinions are used. Technical data are gathered from traditional and Web-based publications, proprietary publications, and informal communications with pertinent vendors. Technology Status Evaluation Reports are drafted by 1 or 2 members of the ASGE Technology Committee, reviewed and edited by the committee as a whole, and approved by the Governing Board of the ASGE. When financial guidance is indicated, the most recent coding data and list prices at the time of publication are provided. For this review, the MEDLINE database was searched through January 2010 for articles related to endoscopic tattooing by using the Keywords tattooing, colonic, endoscopic, India ink, indocyanine green in different search term combinations. Technology Status Evaluation Reports are scientific reviews provided solely for educational and informational purposes. Technology Status Evaluation Reports are not rules and should not be construed as establishing a legal standard of care or as encouraging, advocating, requiring, or discouraging any particular treatment or payment for such treatment.

Colonoscopy and computerized tomography scan are not sufficient to localize right-sided colonic lesions accurately

AIM

Accurate preoperative localization of colonic lesions is critical especially in laparoscopic colectomy where tactile localization is absent particularly in screen-detected tumours. The study aimed to evaluate the accuracy of colonoscopy and double-contrast computerized tomography (CT) scan to localize lesions treated by right hemicolectomy.

METHOD

A retrospective chart review was performed of patients treated by right hemicolectomy under the colorectal service between July 2003 and October 2006. Preoperative tumour location determined by CT scan and colonoscopy was compared with the intra-operative and histopathological findings.

RESULTS

Out of 101 patients, 73 (73%) were for adenoma or cancer, with a final diagnosis of adenocarcinoma in 59 (58%). Preoperative localization was inaccurate in 29% of lesions using both CT and colonoscopy. In the transverse colon, colonoscopy alone was only 37.5% accurate, increasing to 62.5% when information from the CT scan was added.

CONCLUSION

Preoperative localization of right-sided colon cancers using colonoscopy and CT scanning is unreliable in at least 29% of cases. Inaccurate localization of transverse colon tumours risks inadequate lymphadenectomy with an adverse cancer outcome. Preoperative abdominal CT scan improves accuracy but endoscopic tattoo localization should be employed routinely especially in patients undergoing laparoscopic resection.

Small-dose India ink tattooing for preoperative localization of colorectal tumor

INTRODUCTION

India ink tattooing is widely used for tumor localization; however, the tattooing procedure is not yet standardized. This study aims to evaluate the efficacy of small-dose tattooing with sterile India ink using a saline test-injection method.

PATIENTS AND METHODS

Between April 2009 and August 2009, 20 patients underwent colonoscopic tattooing with prepackaged sterile India ink before resection of colorectal tumor. We injected 0.5 cc of India ink at three circumferential sites at the distal tumor using a saline test-injection method. Observation and leakage of India ink were evaluated during laparoscopic surgery, and the diameter of tattooing in the specimen was assessed.

RESULTS

Tattoos were observed intraoperatively in 18 patients (90%). In 2 patients, tattoos were not observed on the serosal surface but were detected on the mucosal surface. Localized leakage of ink was identified during surgery in 1 patient (5%), without fever or abdominal pain. Mean tattoo diameter was 2.1 cm on the serosal surface and 2.0 cm on the mucosal surface.

CONCLUSIONS

Small-dose tattooing with sterile India ink using a saline test-injection method is effective for tumor localization.

Comparison of CT colonography vs. conventional colonoscopy in mapping the segmental location of colon cancer before surgery

Once presence of a colorectal cancer has been diagnosed, a key factor for patient's prognosis in view of surgical intervention is the correct segmental localization and resection of the tumor. The aim of this work was to compare the accuracy of the current gold standard technique, conventional colonoscopy (CC), to computed tomography colonography (CTC) in the segmental localization of tumor. Sixty-five patients (mean age 64; 45 female and 19 male) with colorectal cancer diagnosed at colonoscopy underwent CTC before surgery. In 45 out of 65 cases (69%), patients were referred to CTC after incomplete CC. Reasons were patient intolerance to CC or presence of stenosing cancer, with consistent difficulties in crossing the tract of the colon involved by the lesion. CTC allowed the complete colonic examination in 63/65 cases, since in 2 patients with an obstructing lesion of the sigmoid colon, pneumocolon could not be obtained. However, per patient and per lesion sensitivity of CTC was 100%. Difference from colonoscopy was statistically significant (P < 0.05). In terms of segmental localization of masses, CTC located precisely all lesions, while colonoscopy failed in 16/67 (24%) lesions, though six were missed for incomplete colonoscopy (9%). In the remaining 10/67 (15%) lesions, detected by colonoscopy but incorrectly located, the mismatch occurred in the rectum (n = 3), sigmoid (n = 2), descending (n = 1), transverse (n = 2), ascending colon, and cecum. Agreement between CTC and CC was fair (k value 0.62). Sensitivity, specificity, positive predictive value and negative predictive value of CTC in determining the precise location of colonic masses were respectively 100%, 96%, 85%, and 100%. CT detected hepatic (6/65 patients) and lung metastases (3/65 patients). CT colonography has better performance in the identification of colonic masses (diameter > 3 cm), in the completion of colonic evaluation and in the segmental localization of tumor. CTC should replace colonoscopy for preoperative staging of colorectal cancer.

Colonic tattooing in laparoscopic surgery - making the mark?

OBJECTIVE

Laparoscopic surgery for colorectal cancer is now widespread. Small lesions in the colon can be difficult to palpate and with lack of tactile sensation, it is essential to accurately localize them preoperatively. This is a review article on current methods of tattooing including the use of different agents and associated complications. Aim To review current techniques in preoperative tumour localization and methods used for colonic tattooing including agents used, dosage and potential complications.

METHOD

A literature search (Medline and Pubmed) was performed with manual cross referencing of all articles related to colonic tattooing.

RESULTS

Methods for localizing colonic tumours for laparoscopic resection include preoperative barium enema examination, CT colonography and intraoperative colonoscopy. The most effective method is, however, by tattooing with India ink performed endoscopically before surgery.

CONCLUSION

India ink is a reliable method of marking tumour location within the colon as prelude to laparoscopic resection. Surgeons must, however, be aware of potential complications associated with this technique.

Is there still a role for double-contrast barium enema examination?

The role of double-contrast barium enema examination (DCBE) in screening for colorectal carcinoma has evolved considerably in recent years. This review will discuss the current indications for DCBE and contrast fluoroscopy of the colon and the anticipated future role of these studies.

The usefulness of preoperative colonoscopic tattooing using a saline test injection method with prepackaged sterile India ink for localization in laparoscopic colorectal surgery

BACKGROUND

Laparoscopic surgery for colorectal neoplasm requires precise tumor localization. The authors have assessed the safety and efficacy of colonoscopic tattooing using a saline test injection method with prepackaged sterile India ink for tumor localization in laparoscopic colorectal surgery.

METHODS

Between July 2004 and January 2007, 63 patients underwent colonoscopic tattooing using prepackaged sterile India ink before laparoscopic surgery of colorectal tumors. Patient medical records and operation videos were retrospectively assessed.

RESULTS

Tattoos were visualized intraoperatively in 62 (98.4%) of the 63 patients, and colorectal tumors were accurately localized in 61 patients (96.8%). In one patient, the tattoo could not be detected, whereas in another patient, it was visualized but the serosal surface of the rectosigmoid colon was stained diffusely. Both of these patients underwent intraoperative colonoscopy. Localized leakages of ink were identified in six patients (9.5%) during surgery. However, five of these patients had no symptoms, and the sixth patient, who underwent polypectomy and tattooing simultaneously, felt mild chilling without fever or abdominal pain.

CONCLUSIONS

Preoperative colonoscopic tattooing using a saline test injection method with prepackaged sterile India ink is a safe and effective method for tumor localization in laparoscopic colorectal surgery.

Tumor localization for laparoscopic colorectal surgery

BACKGROUND

Because palpating colonic tumors during laparoscopy is impossible, the precise location of a tumor must be identified before operation. The aim of this study was to evaluate the accuracy of various diagnostic methods that are used to localize colorectal tumors and to propose an adequate localization protocol for laparoscopic colorectal surgery.

METHODS

A total of 310 patients underwent laparoscopy-assisted colectomy between April 2000 and March 2006. We investigated if the locations of the tumors that were estimated preoperatively were consistent with the actual locations according to the operation.

RESULTS

All the tumors were correctly localized and resected. Altogether, 203 patients had complete endoscopic reports available. Colonoscopy was inaccurate for tumor localization in 23 cases (11.3%). In total, 104 patients (33.5%) underwent barium enema; five tumors (4.8%) were not visualized, and three tumors were incorrectly localized. Another group of 94 patients (30.3%) underwent computed tomography (CT) colonography, which identified 91 of 94 lesions (96.8%). Finally, 96 patients (31.0%) underwent endoscopic tattooing; 2 patients (2.1%) did not have tattoos visualized laparoscopically and required intraoperative colonoscopy to localize their lesions during resection. Dye spillage was found in six patients intraoperatively, but only one patient experienced clinical symptoms. Intraoperative colonoscopy was performed in four patients; two of the four were followed by endoscopic tattooing, and the other two underwent intraoperative colonoscopy for localization. All lesions were correctly localized by intraoperative colonoscopy. The accuracy of tumor localization was as follows: colonoscopy (180/203, 88.7%), barium enema (97/104, 93.3%), CT colonography (89/94, 94.7%), endoscopic tattooing (94/96, 97.9%), and intraoperative colonoscopy (4/4, 100%).

CONCLUSIONS

With a combination of methods, localization of tumors for laparoscopic surgery did not seem very different from that during open surgery. Preoperative endoscopic tattooing is a safe, highly effective method for localization. In the case of tattoo failure, intraoperative colonoscopy can be used for accurate localization.

Intraoperative fluoroscopy vs. intraoperative laparoscopic ultrasonography for early colorectal cancer localization in laparoscopic surgery

BACKGROUND

In colorectal cancer (CRC) surgery, precise tumor localization is important for oncologically correct surgery and adequate tumor and lymph node resection margins. During laparoscopic surgery it is difficult to localize early CRC. The aim of this study was to compare the usefulness of two tumor localization techniques; intraoperative fluoroscopy and intraoperative laparoscopic ultrasonography.

METHODS

Seventeen patients with CRC necessitating preoperative marking were alternately allocated to either the fluoroscopy (F) group (n = 8) or the laparoscopic ultrasonography (LU) group (n = 9). A three-step technique was used. At first lesions were localized preoperatively by metallic clips that were colonoscopically applied proximally and distally to the tumor site. Second, computed tomography (CT) colonography was taken to obtain preoperative staging. The location of the metallic clips was confirmed by CT colonography, preoperatively. Third, in the F group, intraoperative fluoroscopy was performed to localize the applied clips. In the LU group, the applied clips were detected from the serosal aspect of the colon using intraoperative laparoscopic ultrasonography.

RESULTS

In all patients, colonoscopic metallic clips were successfully applied and preoperative CT colonography correctly detected the location of the tumor. Marking sites were detected precisely using intraoperative fluoroscopy or intraoperative laparoscopic ultrasonography in all cases, without complications. The mean detection time was 15.8 minutes in the F group and 7.0 minutes in the LU group (p = 0.005). In the LU group, two cases were technically difficult because of interruption of the ultrasound by intestinal air.

CONCLUSIONS

Both intraoperative fluoroscopy and intraoperative laparoscopic ultrasonography are safe and accurate techniques for intraoperative localization of early CRC. With regard to detection time, intraoperative laparoscopic ultrasonography is superior to intraoperative fluoroscopy. However, when there is a massive amount of intestinal air, intraoperative laparoscopic ultrasonography is cumbersome in localizing the lesion. Computed tomography colonography is useful for preoperative tumor localization and might be effective for shortening detection time during surgery.

The Use of Preoperative Endoscopic Tattooing in Laparoscopic Colorectal Cancer Surgery for Endoscopically Advanced Tumors: A Prospective Comparative Clinical Study

BACKGROUND

Endoscopic India ink marking techniques are often used for the intraoperative location of colonic polyps and early stage neoplasms. The aim of this study was to compare how effective this technique is compared with conventional localization methods, as well as its influence on the results of colorectal laparoscopy (LSCRC) for endoscopically advanced tumors.

METHODS

From January 2003 to January 2005, 47 patients with colorectal carcinomas were included in the study. In one group, lesions were localized preoperatively by endoscopic India ink tattooing (n = 21; tattooed group, TG), while conventional methods were used in the others (n = 26; non-tattooed group, NTG). Patients' perioperative clinical and pathoanatomical data were prospectively collected.

RESULTS

Both groups were comparable in age, sex distribution, American Society of Anesthesiologists (ASA) score, body mass index (BMI), technique performed, tumor size and proportion of patients who had previous abdominal surgery. Three patients presented ink spillage without clinical repercussions. Visualization of the correct resection site was higher in the TG (100% vs. 80.8%, P = 0.03). Operative time (147.3 +/- 46.2 vs. 187.0 +/- 52.7 minutes, P = 0.02) and blood loss (99.3 +/- 82.8 vs. 163.6 +/- 96.6 cc, P = 0.03) were lower in the TG. There were no differences between groups regarding peristalsis, introduction of oral intake, hospital stay or intra- and postoperative complication rates. No differences were observed amongst pathoanatomical data studied.

CONCLUSIONS

Preoperative endoscopic tattooing is a safe and effective technique for intraoperative localization of advanced colorectal neoplasms, improving the operative results of LSCRC.

Water enema computed tomography: diagnostic tool in suspicion of colorectal tumor

OBJECTIVES

The aim of this study was to assess the accuracy of water enema multi-row computed tomography for detecting clinically suspected colorectal tumor.

PATIENTS AND METHODS

A water enema multi-row computed tomography (WE-MR-CT) was performed in 128 consecutive patients (71 women, mean age 67.7 years) referred for suspicion of colorectal cancer. We defined at least one centimeter size of the lesion as the threshold of detection. The results of WE-MR-CT were compared with the diagnosis obtained by colonoscopy, pathology or clinical follow-up.

RESULTS

The overall sensitivity and specificity of water enema multi-row CT in identifying patients with colorectal lesions were 95.5% and 93.5%, respectively. The negative predictive value was 98.8% for a 10-mm threshold lesion size. WE-MR-CT allowed identifying synchronous lesions in three cases.

CONCLUSIONS

WE-MR-CT can accurately detect supracentimetric colorectal tumors. The performance of this technique should be further evaluated in prospective studies.

Colorectal cancer screening in average risk individuals

Colorectal cancer is the third leading type of cancer, and the second leading cause of cancer-related death in the United States. Prevention of colorectal cancer should be achievable by screening programs that detect adenomas in asymptomatic patients and lead to their removal. In this manuscript, we review the major screening modalities, the advantages and disadvantages of each approach, the data supporting their use, and various issues affecting the implementation of each test. Screening guidelines will be reviewed, and future techniques for colorectal cancer screening examined.

The role of sigmoidoscopy and colonoscopy in the diagnosis and management of lower gastrointestinal disorders: technique, indications, and contraindications

Flexible sigmoidoscopy and colonoscopy have revolutionized the clinical management of colonic diseases. Colonoscopy has a broad range of indications, including evaluating lower GI symptoms such as lower GI bleeding, evaluating abnormal radiographic findings, and screening and surveillance for colon cancer. Colonoscopy is increasingly being used therapeutically. Patient evaluation, patient instructions, and colonic preparation before colonoscopy are essential for safe and efficient colonoscopy. Intravenous sedation reduces patient pain and anxiety during colonoscopy, but requires monitoring by pulse oximetry and automated measurements of vital signs. An experienced colonoscopist can complete colonoscopy in 90% or more of cases, using maneuvers to maintain the colonic lumen in view, straighten the colonoscope, and avoid looping during colonic intubation.

Tattoo of colonic neoplasms in 113 patients with a new sterile carbon compound

BACKGROUND

Endoscopic marking of intestinal lesions is essential when difficulty is anticipated with subsequent localization during surgical resection or postpolypectomy surveillance. The most commonly used indelible marker has been India ink, which must be diluted and sterilized, a cumbersome process. SPOT, a prepackaged, sterile Food and Drug Administration-approved formulation of pure carbon particles in suspension, eliminates the need for preinjection preparation.

METHODS

Ten patients with colonic polyps deemed endoscopically unresectable or malignant-appearing had the area surrounding the lesions injected with SPOT and subsequently underwent surgical resection. An additional 103 patients underwent colonoscopic injection with SPOT and were followed endoscopically or underwent surgery at another hospital.

RESULTS

The SPOT injection sites were visible to the surgeons in all 10 cases. On histopathologic evaluation, none of the resection specimens exhibited necrosis or abscess formation. In total, there were 118 SPOT injections in 113 patients; none had fever, abdominal pain, or any other signs or symptoms of inflammation develop. In the nonoperated group, 42 patients subsequently underwent colonoscopies at our institution, and in all cases stains were readily identifiable at the injection sites.

CONCLUSIONS

SPOT is a safe and effective marker for use at colonoscopy when surgical resection is anticipated. It is also useful for endoscopic follow-up of patients who have not undergone surgery.

Electronic three-dimensional imaging of intestinal endoscopy

Endoscopists, especially those investigating the colon, need to know where the tip of the instrument is and whether the tube is kinking. A three-dimensional real-time imaging system consisting of sensors, within or taped to the endoscope, to detect weak electric currents in a wire grid below the mattress yields the information needed and should greatly facilitate performance and teaching of endoscopy.