The Effects of Preoperative Endoscopic Tattooing on Distal Surgical Margin and Ileostomy Rates in Laparoscopic Rectal Cancer Surgery: A Prospective Randomized Study

Elderly Rectal Cancer: An Updated Review

PURPOSE OF REVIEW

Treatment of rectal cancer patients of advanced age should be modulated by life expectancy and tolerance. Due to the rapid advance of this field, we aim to conduct an updated review of this topic.

RECENT FINDINGS

The field of elderly rectal cancer has advanced a lot. This review covers all the treatment aspects of elderly rectal cancer, including the prognostic factor, surgery, radiotherapy, chemotherapy, and palliative treatment. We also provide the future aspect of the management of elderly rectal cancer. The advancement of prognostic factor research, surgery, radiotherapy, chemotherapy, and palliative treatment has made the care of elderly rectal cancer patients better. The future of these fields should focus on the definition of the elderly and the application of particle therapy.

Endoscopic ultrasound-guided injection of carbon nanoparticles suspension to label rectal cancer before neoadjuvant chemoradiotherapy: a retrospective cohort study

Background

Localization of the primary tumor and ensuring safe distal surgical margins (DSMs) following neoadjuvant chemoradiotherapy (nCRT) are challenging in locally advanced rectal cancers (LARCs). This study investigated the effectiveness of carbon nanoparticles suspension (CNS) for labeling the primary tumor and allowing precise tumor resection after nCRT.

Methods

Clinicopathological data of LARC patients who underwent nCRT followed by laparoscopic radical anal preservation surgery at our center between January 2018 and February 2023 were prospectively collected. The patients were divided into the CNS tattooed (CNS) and non-tattooed (control) groups. In the CNS group, CNS was injected in four quadrants on the anal side 1 cm away from the lower tumor margin. DSMs were determined through intraoperative distal rectal examination in the control group and observation of CNS tattoos in the CNS group. DSM lengths and positive DSM rates were compared between the two groups to analyse the feasibility and effectiveness of CNS for labeling LARCs before nCRT.

Results

There was no statistically significant difference in the basic demographic data, effectiveness of nCRT, or post-operative recovery rates between the two groups (all P > 0.05). In the CNS group, CNS tattoos were observed on the outside of the rectal wall, with an overall efficiency of 87.1% (27/31). The CNS group had fewer positive DSMs and safer DSM lengths (2.73 ± 0.88 vs 2.12 ± 1.15 cm, P = 0.012) than the control group (P < 0.05).

Conclusions

Endoscopic ultrasound-guided injection of CNS tattoos before nCRT could effectively label the LARCs, ensuring safe DSMs during anus-preserving surgeries (Chictr.org.cn No.: ChiCTR2300068991).

The effect of preoperative endoscopic tattooing on lymph node retrieval in colorectal cancer: a systematic review and meta-analysis

PURPOSE

The effect of preoperative endoscopic tattooing (ET) on accurate colorectal cancer localization and resection has been well established. However, its effect on lymph node (LN) retrieval remains unclear. The purpose of this study was to systematically compare LN retrieval between patients with colorectal cancer who underwent preoperative ET and those who did not.

METHODS

A systematic search for relevant studies was conducted using the following databases: PubMed, Embase, and Web of Science. Studies that compared LN retrieval in patients with colorectal cancer with and without preoperative ET were included. Weighted pooled odds ratio (OR) and mean difference (MD) with the corresponding 95% confidence intervals (CIs) for all outcomes using the random-effects model were calculated.

RESULTS

10 studies, including 2231 patients with colorectal cancer were included. Six studies reported total LN yield and showed significantly higher LN yield in the tattooed group (MD:2.61; 95% CI:1.01-4.21, P=0.001). Seven studies reported the number of patients with adequate LN retrieval and showed a significantly higher number of patients with adequate LN retrieval in the tattooed group (OR:1.89, 95% CI:1.08-3.32, P=0.03). However, subgroup analysis revealed that both outcomes were only statistically significant in patients with rectal cancer, and not in patients with colon cancer.

CONCLUSIONS

Our results suggest that preoperative ET is associated with increased LN retrieval in patients with rectal cancer, but not in colon cancer. Further large-scale randomized control trials are necessary to validate our findings.

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.

Usefulness of Endoscopic Tattooing Before Neoadjuvant Therapy in Patients with Clinical Complete Response in Locally Advanced Rectal Cancer for Providing a Safe Distal Surgical Margin

Background: Endoscopic tattooing of colorectal tumors enables tumor localization and determination of appropriate surgical margins. It becomes very difficult to detect the distal surgical margins (DSMs) of rectal tumors in patients who obtain clinical complete response (cCR) after neoadjuvant therapy. In this study, our aim is to examine the benefits of endoscopic tattooing of the tumor before neoadjuvant therapy in patients with locally advanced rectal cancer in accurate localization of the previous tumor and in providing appropriate DSMs in cases with cCR. Patients and Methods: The patients who were diagnosed with locally advanced rectal cancer, received neoadjuvant therapy and subsequently achieved cCR, and underwent surgery between January 2015 and October 2020 were included in the study. The patients were divided into two groups according to whether they were endoscopically tattooed before neoadjuvant chemoradiotherapy. Results: A total of 49 cases were included in the study. Significantly better DSMs were observed especially in female gender in the tattooed group. DSMs were found to be closer to the resection margins in the nontattooed group. It was found that endoscopic tattooing had a significant effect on the DSM in the regression analysis (P = .06, R² = 0.47). It was determined that laparoscopy or open surgery alone did not differ in terms of DSMs but open surgery together with tattooing was found to be strongly effective in providing larger DSMs. Conclusion: In locally advanced rectal cancer, endoscopic tattooing of the distal margin of the tumor before neoadjuvant therapy is a reliable and effective method for obtaining a safe DSM and not leaving the residual tumor at the lower end of anastomosis, especially in cases of cCR.

When and How To Use Endoscopic Tattooing in the Colon: An International Delphi Agreement

BACKGROUND & AIMS

There is a lack of clinical studies to establish indications and methodology for tattooing, therefore technique and practice of tattooing is very variable. We aimed to establish a consensus on the indications and appropriate techniques for colonic tattoo through a modified Delphi process.

METHODS

The baseline questionnaire was classified into 3 areas: where tattooing should not be used (1 domain, 6 questions), where tattooing should be used (4 domains, 20 questions), and how to perform tattooing (1 domain 20 questions). A total of 29 experts participated in the 3 rounds of the Delphi process.

RESULTS

A total of 15 statements were approved. The statements that achieved the highest agreement were as follows: tattooing should always be used after endoscopic resection of a lesion with suspicion of submucosal invasion (agreement score, 4.59; degree of consensus, 97%). For a colorectal lesion that is left in situ but considered suitable for endoscopic resection, tattooing may be used if the lesion is considered difficult to detect at a subsequent endoscopy (agreement score, 4.62; degree of consensus, 100%). A tattoo should never be injected directly into or underneath a lesion that might be removed endoscopically at a later point in time (agreement score, 4.79; degree of consensus, 97%). Details of the tattoo injection should be stated clearly in the endoscopy report (agreement score, 4.76; degree of consensus, 100%).

CONCLUSIONS

This expert consensus has developed different statements about where tattooing should not be used, when it should be used, and how that should be done.

Application of Carbon Nanoparticles in Tracing Lymph Nodes and Locating Tumors in Colorectal Cancer: A Concise Review

Background

Accurate lymph node (LN) staging has considerably prognostic and therapeutic value in patients with colorectal cancer (CRC). The purpose of this study is to evaluate the feasibility of applying carbon nanoparticles (CNPs) to track LN metastases in CRC.

Methods

Two researchers independently screened publications in PubMed, EMBASE, Cochrane and Ovid MEDLINE databases. The keywords were (carbon nanoparticles OR activated carbon nanoparticles) AND (colon cancer OR rectal cancer OR colorectal cancer). Titles and abstracts of the articles were meticulously read to rule out potential publications. Next, full texts of the ultimately obtained eligible publications were retrieved and analyzed in detail.

Results

The search produced 268 publications, and 140 abstracts were identified after a bibliographic review. Finally, 20 studies relevant to our subject were obtained; however, only 14 papers met our inclusion criteria and were included for final review. All studies included have compared the control group with carbon nanoparticles group (control group, defined as nontattooed group; and carbon nanoparticles group, defined as administering carbon nanoparticles during surgery) for their efficacy in intraoperative detecting and positioning. After analysis, appreciably less amount of bleeding (3/5 trials), shorter operation time (2/4 trials), and shorter time to detect lesions and dissect LNs (2/2 trials) were revealed in CNPs group compared to control group. Thirteen studies have recorded the numbers of the harvested LNs in both groups; meanwhile, CNPs group shows superiority to control group in LN retrieval as well (11/13 trials), which also could effectively aid in locating and harvesting more LNs with diameter below 5 mm.

Conclusion

The tracing technique for CNPs is a safe and useful strategy both in localizing tumor and tracing LNs in CRC surgery. But there is still a need for more randomized controlled trials to further establish its contribution to patient survival.

Accurate localization of rectal cancer using near infrared ray-guided surgery with intra-operative colonoscopy and da Vinci Firefly technology

Accurate localization of the tumor during robot-assisted laparoscopic surgery for rectal cancer is crucial. Several techniques have been described, but each has its shortcomings. We developed a new technique of near infrared ray-guided surgery (NIRGS) to localize the tumor accurately, using intra-operative colonoscopy and da Vinci Firefly technology. After clamping the oral side of the tumor, the colonoscope was inserted. In the normal visible light mode, we could not recognize the endoscopic light; however, after changing to the Firefly mode, the endoscopic light was seen clearly. Using this simple and new technique, we could locate the tumor easily and accurately. We performed this technique in 12 patients and detected the location of the tumor clearly in all, without any procedure-related complications. Based on these findings, NIRGS is a useful and safe technique for detecting tumor location during robot-assisted laparoscopic surgery for rectal cancer.

Size and lipid modification determine liposomal Indocyanine green performance for tumor imaging in a model of rectal cancer

Localization of rectal tumors is a challenge in minimally invasive surgery due to the lack of tactile sensation. We had developed liposomal indocyanine green (Lip-ICG) for localization of rectal tumor. In this study we evaluated the effects of liposome size and lipid PEGylation on imaging. We used an endoscopically-guided orthotopic experimental rectal cancer model in which tumor fluorescence was determined at different time points after intravenous (i.v.) administration of Lip-ICG and PEGylated liposomes (PEG-Lip-ICG). Signal intensity was measured by tumor-to-background ratio (TBR), or normalized TBR (compared to TBR of free ICG). Fluorescence microscopy of tumor tissue was performed to determine fluorescence localization within the tissue and blood vessels. Liposomes of 60 nm showed an increased TBR compared with free ICG at 12 hours after i.v. injection: normalized TBR (nTBR) = 3.11 vs. 1, respectively (p = 0.006). Larger liposomes (100 nm and 140 nm) had comparable signal to free ICG (nTBR = 0.98 ± 0.02 and 0.78 ± 0.08, respectively), even when additional time points were examined (0.5, 3 and 24 hours). PEG-Lip- ICG were more efficient than Lip-ICG (TBR = 4.2 ± 0.18 vs. 2.5 ± 0.12, p < 0.01) presumably because of reduced uptake by the reticulo-endothelial system. ICG was found outside the capillaries in tumor margins. We conclude that size and lipid modification impact imaging intensity.

Using India Ink as a Sensor for Oximetry: Evidence of its Safety as a Medical Device

Clinical EPR spectroscopy is emerging as an important modality, with the potential to be used in standard clinical practice to determine the extent of hypoxia in tissues and whether hypoxic tissues respond to breathing enriched oxygen during therapy. Oximetry can provide important information useful for prognosis and to improve patient outcomes. EPR oximetry has many potential advantages over other ways to measure oxygen in tissues, including directly measuring oxygen in tissues and being particularly sensitive to low oxygen, repeatable, and non-invasive after an initial injection of the EPR-sensing material is placed in the tumor. The most immediately available oxygen sensor is India ink, where two classes of carbon (carbon black and charcoal) have been identified as having acceptable paramagnetic properties for oximetry. While India ink has a long history of safe use in tattoos, a systematic research search regarding its safety for marking tissues for medical uses and an examination of the evidence that differentiates between ink based on charcoal or carbon black has not been conducted.

METHODS

Using systematic literature search techniques, we searched the PubMed and Food and Drug Administration databases, finding ~1000 publications reporting on adverse events associated with India/carbon based inks. The detailed review of outcomes was based on studies involving >16 patients, where the ink was identifiable as carbon black or charcoal.

RESULTS

Fifty-six studies met these criteria. There were few reports of complications other than transient and usually mild discomfort and bleeding at injection, and there was no difference in charcoal vs. carbon black India ink.

CONCLUSIONS

India ink was generally well tolerated by patients and physicians reported that it was easy to use in practice and used few resources. The risk is low enough to justify its use as an oxygen sensor in clinical practice.