Safety and Oncological Outcomes of Bevacizumab Therapy in Patients With Advanced Colorectal Cancer and Self-expandable Metal Stents

Malignant Acute Colonic Obstruction: Multidisciplinary Approach for Endoscopic Management

Patients presenting with acute colonic obstruction are usually evaluated in the emergency department and multiple specialties are involved in the patients' management. Pre-treatment evaluation is essential in order to establish the correct endoscopic indication for stent implantation. Contrast-enhanced imaging could allow the exclusion of benign causes of colonic obstruction and evaluation of the length of malignant stricture. Endoscopic stenting is the gold standard of treatment for palliative indications whereas there are still concerns about its use as a bridge to surgery. Different meta-analyses showed that stenting as a bridge to surgery improves short-term surgical outcomes but has no role in improving long-term outcomes. Multidisciplinary evaluation is also essential in patients that may be started on or are currently receiving antiangiogenic agents because endoscopic stenting may increase the risk of perforation. Evidence in the literature is weak and based on retrospective data. Here we report on how to correctly evaluate a patient with acute colonic malignant obstruction in collaboration with other essential specialists including a radiologist, surgeon and oncologist, and how to optimize the technique of endoscopic stenting.

Efficacy and Safety of Fluoroscopy-Guided Self-Expandable Metal Stent Placement for Treatment of Malignant Colorectal Obstruction

AIM

To investigate long-term outcomes after SEMS insertion in patients with malignant colorectal obstruction and to identify the risk factors for complications.

METHODS

The data of 119 patients with malignant colorectal obstruction who received SEMS insertion between March 2014 and February 2020 were retrospectively analyzed. Patients were divided into two groups according to the intent of treatment, i.e., stenting as "bridge to surgery" (surgical group) and stenting for palliation (palliative group). Technical and clinical success rates and incidence of complications were compared between the two groups.

RESULTS

The overall technical and clinical success rates were 97.5% and 96.6%, respectively. The technical and clinical success rates and complication rate were comparable between the two groups. In the palliative group, the mean stent patency time was 230 days. Patency rates were not significantly different between primary CRC and recurrent CRC. Incidence of complications was higher in the palliative group than in the surgical group. In multivariate analysis, chemotherapy before stent implantation may increase the risk of stent-related complications, whereas chemotherapy after stent implantation did not. Additionally, the factors independently associated with complications were female sex and preoperative chemotherapy.

CONCLUSIONS

SEMS under fluoroscopic guidance is a safe and effective treatment for malignant colorectal obstruction. For patients with resectable CRC, stent placement can serve as a bridge to elective surgery. It is worth noting that adjuvant chemotherapy between SEMS and surgery did not increase the complications. For patients with recurrent CRC, stent placement can relieve symptoms, alleviate pain, and improve quality of life.

Oncologic safety of colonic stenting as a bridge to surgery in left-sided malignant colonic obstruction: Current evidence and prospects

Approximately 7%-29% of patients with colorectal cancer present with colonic obstruction. The concept of self-expandable metal stent (SEMS) insertion as a bridge to surgery (BTS) is appealing. However, concerns on colonic stenting possibly impairing oncologic outcomes have been raised. This study aimed to review current evidence on the short- and long-term oncologic outcomes of SEMS insertion as BTS for left-sided malignant colonic obstruction. For short-term outcomes, colonic stenting facilitates a laparoscopic approach, increases the likelihood of primary anastomosis without a stoma, and may decrease postoperative morbidity. However, SEMS-related perforation also increases local recurrence and impairs overall survival. Moreover, colonic stenting may cause negative oncologic outcomes even without perforation. SEMS can induce shear forces on the tumor, leading to increased circulating cancer cells and aggressive pathological characteristics, including perineural and lymphovascular invasion. The conflicting evidence has led to discordant guidelines. Well-designed collaborative studies that integrate both oncologic outcomes and data on basic research (e.g., alteration of circulating tumors) are needed to clarify the actual benefit of colonic stenting as BTS.

Safety of endoscopy in patients undergoing treatments with antiangiogenic agents: A 5-year retrospective review

BACKGROUND

Antiangiogenic agents (AAs) are increasingly used to treat malignant tumors and have been associated with gastrointestinal (GI) bleeding and perforation. Elective surgeries and endoscopy are recommended to be delayed for 31 d until after AAs treatment. Data regarding the safety of endoscopy while on antiangiogenic agents is extremely limited. No guidelines are in place to address the concern about withholding these anti-angiogenic drugs.

AIM

To evaluate the risks of endoscopy in patients on antiangiogenic agents from 2015 to 2020 at our institution.

METHODS

This is a single centered retrospective study approved by the institutional review board statement of the institution. Patients that underwent endoscopy within 28 d of antiangiogenic agents’ treatment were included in the study. Primary outcome of interest was death, and secondary outcomes included perforation and GI bleeding. Data were analyzed utilizing descriptive statistics. Fifty-nine patients were included in the final analysis and a total of eighty-five procedures were performed that were characterized as low risk and high risk.

RESULTS

Among the 59 patients a total of 85 endoscopic procedures were performed with 24 (28.2%) categorized as high-risk and 61 (71.8%) procedures as low-risk. Of the total number of patients, (50%) were on bevacizumab and the rest were on imatinib (11.7%), lenvatinib (6.7%) and, ramucirumab (5%). The average duration between administration of AAs and the performance of endoscopic procedures was 9.9 d. No procedure-related adverse events were noted among our study population. We did observe two deaths with one patient, on lenvatinib for metastatic hepatocellular carcinoma, who had persistent bleeding despite esophageal variceal banding and died 4 d later from hemorrhagic shock. Another patient was diagnosed with acute myeloid leukemia died 24 d after an esophagogastroduodenoscopy with biopsy after transition to comfort care.

CONCLUSION

As per this single center retrospective study, the rate of endoscopic procedure-related adverse events and death within 28 d of AA administration appears to be low.

Self-expanding metal stent insertion by colorectal surgeons using a two-person approach colonoscopy without fluoroscopic monitoring in the management of acute colorectal obstruction: a 14-year experience

BACKGROUND

Placement of a self-expanding metal stent (SEMS) in patients presenting with an acute colorectal obstruction (ACO) may obviate emergency surgery (ES), potentially effectively palliating incurable tumors, acting as a bridge to surgery (BTS) in patients with operable or potentially operable tumors and achieving effective decompression of other ACO. We present our experience with SEMS insertion by colorectal surgeons without fluoroscopic monitoring for ACO especially for acute malignant colorectal obstruction (AMCO) for nearly a 14-year period (2007-2020).

AIM

To explore the safety and effectiveness of SEMS insertion in the management of ACO by colorectal surgeons using a two-person approach colonoscopy without fluoroscopic monitoring.

METHODS

We reviewed the medical records of patients retrospectively to identify all patients presenting to our unit with ACO especially with AMCO who had stenting carried out to achieve colonic decompression. All 434 procedures were performed by colorectal surgeons using a two-person approach colonoscopy without fluoroscopic monitoring.

RESULTS

The overall technique success rate and clinic success rate by SEMS insertion were 428/434 (98.6%) and 412/434 (94.9%). The overall incidence of complications by SEMS insertion was 19/434 (4.4%). The complications included clinical perforation (6/434, 1.4%); stent migration (2/434, 0.5%), 1 of which re-stent; stent detachment (fell off) (3/434, 0.7%), none of them with re-stent; stool impaction (6/434, 1.4%), 1 of which re-stent; and abdominal or anal pain (2/434, 0.5%). There was no hemorrhage in any of the 434 patients.

CONCLUSIONS

SEMS insertion is a relatively safe and effective technique for colonic decompression in dealing with ACO as either a BTS or as a palliative measure. It is also a solution to other causes of ACO such as recurrent tumor, benign diseases, or extra-luminal compression. Therefore, ES was largely avoided.

EGFL6 promotes colorectal cancer cell growth and mobility and the anti-cancer property of anti-EGFL6 antibody

BACKGROUND

The availability of a reliable tumor target for advanced colorectal cancer (CRC) therapeutic approaches is critical since current treatments are limited. Epidermal growth factor-like domain 6 (EGFL6) has been reported to be associated with cancer development. Here, we focused on the role of EGFL6 in CRC progression and its clinical relevance. In addition, an anti-EGFL6 antibody was generated by phage display technology to investigate its potential therapeutic efficacy in CRC.

RESULTS

EGFL6 expression significantly increased in the colon tissues from CRC patients and mice showing spontaneous tumorigenesis, but not in normal tissue. Under hypoxic condition, EGFL6 expression was enhanced at both protein and transcript levels. Moreover, EGFL6 could promote cancer cell migration invasion, and proliferation of CRC cells via up-regulation of the ERK/ AKT pathway. EGFL6 also regulated cell migration, invasion, proliferation, and self-renewal through EGFR/αvβ3 integrin receptors. Treatment with the anti-EGFL6 antibody EGFL6-E5-IgG showed tumor-inhibition and anti-metastasis abilities in the xenograft and syngeneic mouse models, respectively. Moreover, EGFL6-E5-IgG treatment had no adverse effect on angiogenesis and wound healing CONCLUSIONS: We demonstrated that EGFL6 plays a role in CRC tumorigenesis and tumor progression, indicating that EGFL6 is a potential therapeutic target worth further investigation.

Biopsy sampling during self-expandable metallic stent placement in acute malignant colorectal obstruction: a narrative review

BACKGROUND

Histopathology is a crucial part of diagnosis and treatment guidance of colorectal cancer. In Denmark, it is not routine to biopsy during self-expandable metallic stent (SEMS) placement as a treatment option for acute colorectal obstruction of unknown etiology. This is due to lack of knowledge about the risks of hemorrhage, and thus the risk to aggravate the deteriorating overview conditions. Therefore, the aim of this study is to investigate whether there is evidence to avoid biopsy sampling during acute SEMS placement.

METHODS

The PubMed, Embase, and Cochrane Library databases were searched for relevant studies. Studies were included if they described biopsy sampling in relation to SEMS placement. Additionally, national and international guidelines were scrutinized on Google and by visiting the websites of national and international gastrointestinal societies.

RESULTS

In total, 43 studies were included in the review. Among these, one recommended biopsy during SEMS placement, three advised against biopsy, 23 just reported biopsy was performed during the procedure, and 16 reported biopsy before or after the procedure, or the timing was not specified. Among the 12 included guidelines, only two described biopsy during SEMS placement.

CONCLUSION

The literature on the subject is limited. In 24 of the 43 included studies, biopsy sampling was done during SEMS placement without reporting a decrease in the technical success rate. The included guidelines were characterized by a general lack of description of whether biopsy during SEMS placement should be performed or not. Prospective studies are needed in order to establish the real risk of hemorrhage, if any, when a biopsy is obtained.

The Association of Coloproctology of Great Britain and Ireland consensus guidelines in emergency colorectal surgery

AIM

There is a requirement for an expansive and up to date review of the management of emergency colorectal conditions seen in adults. The primary objective is to provide detailed evidence-based guidelines for the target audience of general and colorectal surgeons who are responsible for an adult population and who practise in Great Britain and Ireland.

METHODS

Surgeons who are elected members of the Association of Coloproctology of Great Britain and Ireland Emergency Surgery Subcommittee were invited to contribute various sections to the guidelines. They were directed to produce a pathology-based document using literature searches that were systematic, comprehensible, transparent and reproducible. Levels of evidence were graded. Each author was asked to provide a set of recommendations which were evidence-based and unambiguous. These recommendations were submitted to the whole guideline group and scored. They were then refined and submitted to a second vote. Only those that achieved >80% consensus at level 5 (strongly agree) or level 4 (agree) after two votes were included in the guidelines.

RESULTS

All aspects of care (excluding abdominal trauma) for emergency colorectal conditions have been included along with 122 recommendations for management.

CONCLUSION

These guidelines provide an up to date and evidence-based summary of the current surgical knowledge in the management of emergency colorectal conditions and should serve as practical text for clinicians managing colorectal conditions in the emergency setting.

Systemic Chemotherapy is a Promising Treatment Option for Patients with Colonic Stents: A Review

Approximately 10% of patients with colorectal cancer (CRC) develop malignant large bowel obstruction (MLBO) at diagnosis. Furthermore, for 35% of patients with MLBO, curative primary tumor resection is unfeasible because of locally advanced disease and comorbidities. The practice of placing a self-expandable metallic stent (SEMS) has dramatically increased as an effective palliative treatment. Recent advances in systemic chemotherapy for metastatic CRC have significantly contributed to prolonging patients' prognosis and expanding the indications. However, the safety and efficacy of systemic chemotherapy in patients with SEMS have not been established. This review outlines the current status of this relatively new therapeutic strategy and future perspectives. Some reports on this topic have demonstrated that 1) systemic chemotherapy and the addition of molecular targeted agents contribute to prolonged survival in patients with SEMS; 2) delayed SEMS-related complications are a major concern, and this requires strict patient monitoring; however, primary tumor control by chemotherapy might result in decreased complications, especially regarding re-obstruction; and 3) using bevacizumab could be a risk factor for SEMS-related perforation, which may be lethal. Although this relatively new approach for unresectable stage IV obstructive CRC requires a well-planned clinical trial, this therapy could be promising for patients who are unideal candidates for emergency surgery and require immediate systemic chemotherapy.

Comprehensive literature review of randomized clinical trials examining novel treatment advances in patients with colon cancer

The treatment of colon cancer has had numerous recent advances, in terms of surgical approach, adjuvant therapies, and more. In this review, the authors examine randomized clinical trials comparing open surgery to laparoscopic surgery (including total mesocolic excision), and also examine the role of robotic surgery. Novel surgical techniques including the no-touch technique, side-to-side anastomosis, suture technique, complete mesocolic excision (CME) with central vascular ligation (CVL), and natural orifice transluminal endoscopic surgery (NOTES) are outlined. The role of placing endoscopic self-expandable metal stents (SEMS) for colonic obstruction is compared and contrasted with the surgical approach, and the effect that the anti-VEGF inhibitor bevacizumab may have on this side effect profile is further explored. The role of the resection of the primary tumor in the setting of metastatic disease is examined with respect to survival benefit. Pathways of perioperative care which can accelerate post-surgical recovery, including enhanced recovery after surgery (ERAS) are examined. The role of adjuvant chemotherapy in patients with high-risk stage II and patients with stage III disease is examined, along with the role on circulating tumor DNA (ctDNA) as well as with the biologic targeted agents cetuximab and bevacizumab. Lastly, the authors detail the postoperative surveillance schedules after surgical resection with respect to survival outcomes.

Long-term outcomes of stent-related perforation in malignant colon obstruction: a systematic review and meta-analysis

PURPOSE

The placement of self-expandable metallic stents as a bridge to surgery in malignant colon obstruction is concerning due to the long-term oncological results reported in recent published studies. The aim of this study was to evaluate the oncological consequences of stent-related perforations in patients with malignant colon obstruction and potentially curable disease.

METHODS

MEDLINE, Cochrane Library, Ovid and ISRCTN Registry were searched, with no restrictions. We performed five meta-analyses to estimate the pooled effect sizes by using a random-effect model. The outcomes were global, locoregional and systemic recurrence rate and 3 and 5 year-survival rate depending on the presence or absence of stent-related perforation.

RESULTS

Thirteen studies (950 patients) were included. The overall rate of stent-related perforation was 8.9%. The global recurrence rate was significantly higher in stent-related perforation group (41.2 vs. 30.8%; OR 1.70; 95%CI: 1.02-2.84; p = 0.04). Locoregional recurrence rate was higher in the perforated group than in the non-perforated group (26.6 vs. 12.5%), with statistically significant differences (OR 2.41; 95% CI:1.33-4.34; p = 0.004). No significant differences were found in systemic recurrence rate (13.6 vs. 20.5%; OR 0.77; 95%CI: 0.35-1.7; p = 0.51); 3-year overall survival rate (65.4 vs. 74.8%; OR 0.63; 95% CI:0.29-1.39; p = 0.25) and 5-year overall survival rate (48.3 vs. 58.6%; OR 0.67; 95%CI: 0.27-1.65; p = 0.38).

CONCLUSION

Stent-related perforation is associated with an increased risk of global and locoregional recurrence. The successful placement of the stent as a bridge to surgery in the curative purpose of patients with obstructed colon cancer does not exclude the presence of underlying perforation, with the consequent danger of disease spread. PROSPERO registration number: CRD42020152817.