Colon metal stents as a bridge to surgery had no significant effects on the perineural invasion: a retrospective study

The optimal surgery timing after stenting in colorectal cancer patients with malignant obstruction: additionally compared with emergency surgery

BACKGROUND

This study aimed to determine short-term and long-term outcomes according to time intervals after stenting and compared them with those of emergency surgery (ES) in colorectal cancer (CRC) with malignant obstruction.

METHODS

CRC with malignant obstructions was reviewed retrospectively between January 2008 and July 2018. Of a total of 539 patients who visited the emergency room and underwent ES, 133 were enrolled in the ES group. Of a total of 567 patients who initially received stenting and subsequently underwent elective surgery, 220 were enrolled in the SEMS group. The interval between SEMS placement and elective surgery was classified as < 11 days, 11-17 days, and > 17 days.

RESULTS

For those who received SEMS (n = 220), those with a time interval of 11-17 days (n = 97) had fewer hospital days than those with a time interval of < 11 days (n = 68) (8 days vs. 15 days) and less stoma formation than those with a time interval of > 17 days (n = 55) (1.0% vs. 14.6%). Multivariable analysis revealed a decreased risk of death for the group with a time interval of 11-17 days (20.6%) compared to the ES group (31.6%) (hazard ratio: 0.48; 95% confidence interval: 0.24-0.97). Disease-free survival was comparable between the SEMS and ES groups regardless of the time interval (log-rank p = 0.52).

CONCLUSIONS

The time interval of 11-17 days after stenting to elective surgery appeared to be associated with the most favorable outcomes.

Delaying surgery for optimization after colonic stent bridging is safe for left-sided malignant large bowel obstruction: Result from 10-year experience and risks factor analysis

AIM

To evaluate the operative and oncological results after colonic stent bridging for left-sided malignant large bowel intestinal obstruction and the risk factors for survival and recurrence after definitive surgery.

METHODOLOGY

Consecutive patients who underwent colonic stenting for malignant left-sided colonic obstruction were included. Patients for palliative stenting or emergency surgery, patient with low rectal tumour or peritoneal metastasis were excluded. The primary outcome was overall survival. Secondary outcomes included stent success rate, stenting related complications, rate of stoma formation and long-term oncological outcome including recurrence rate and recurrence free survival rate.

RESULTS

From June 2011 to June 2021, a total of 222 patients underwent colonic stenting. 112 patients were bridged to surgery after initial stenting, but 7 patients dropped out. Overall survival was 35 months (IQR = 17.75-75.25 months) in the early operation group, 30 months (IQR = 17.5-49.5 months) in the delayed surgery group HR 0.981 (95%CI 0.70-1.395, p = 0.907). Sensitivity analysis performed by excluding stent complications and emergency surgery yielded the same conclusion. Overall stenting complications rate was 17.1%. 11 patients (10.4%) required emergency surgery.

CONCLUSION

There was no difference between early and delayed surgery groups (>4weeks) in the overall survival and recurrence in patients who had stent-bridge to surgery for malignant left colonic obstruction. It is safe to defer definitive surgery to optimize patients and allow better recovery from initial obstruction after colonic stenting before definitive surgery without adversely affecting the oncological outcomes.

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.

Colonic stent for bridge to surgery for acute left-sided malignant colonic obstruction: A review of the literature after 2020

It has been found that 8%-29% of colorectal cancers are obstructive. The use of “stent as bridge to surgery” is one of the most debated topics in obstructive left-sided colorectal cancer management. The endoscopic placement of a self-expanding metallic stent as bridge to surgery (BTS) could turn an emergency surgery to an elective one, increasing the number of primary anastomoses instead of stoma and facilitating the laparoscopic approach instead of an open one. However, in recent years the possible risk of perforations and microperforations facilitating cancer spread related to the use of self-expanding metallic stent for BTS has been highlighted. Therefore, despite the useful short-term outcomes related to BTS, the recent literature has focused on long-term outcomes investigating the disease-free survival, the recurrence rate and the overall survival. Due to discordant data, international guidelines are still conflicting, and the debate is still open. There is not agreement about using self-expanding metallic stent for BTS as the gold standard.

Self-expanding metal stent placement and pathological alterations among obstructive colorectal cancer cases

BACKGROUND

Experimental studies suggest that self-expanding metal stents (SEMSs) enhance the aggressive behavior of obstructive colorectal cancer. The influence of SEMS placement on pathological alterations remains to be elucidated.

AIM

To determine whether SEMS placement is associated with molecular or pathological features of colorectal carcinoma tissues.

METHODS

Using a nonbiased molecular pathological epidemiology database of patients with obstructive colorectal cancers, we examined the association of SEMS placement with molecular or pathological features, including tumor size, histological type, American Joint Committee on Cancer (AJCC)-pTNM stage, and mutation statuses in colorectal cancer tissues compared with the use of transanal tubes. A multivariable logistic regression model was used to adjust for potential confounders.

RESULTS

SEMS placement was significantly associated with venous invasion (P < 0.01), but not with the other features examined, including tumor size, disease stage, mutation status, and lymphatic invasion. In both the univariable and multivariable models with adjustment for potential factors including tumor location, histological type, and AJCC-pT stage, SEMS placement was significantly associated with severe venous invasion (P < 0.01). For the outcome category of severe venous invasion, the multivariable odds ratio for SEMS placement relative to transanal tube placement was 19.4 (95% confidence interval: 5.24–96.2). No significant differences of disease-free survival and overall survival were observed between SEMS and transanal tube groups.

CONCLUSION

SEMS placement might be associated with severe venous invasion in colorectal cancer tissue, providing an impetus for further investigations on the pathological alterations by SEMSs in colorectal cancer development.

Colonic stenting as a bridge to surgery for obstructive colon cancer: is it safe in the long term?

BACKGROUND

The placement of a self-expanding metal stent in patients with obstructive colon cancer is used as a bridge to surgery. However, due to a lack of consensus and insufficient data, the long-term oncologic outcomes after colonic SEMS placement remain unclear. We assessed the long-term oncologic outcomes and adverse effects of colonic stenting for malignant colonic obstruction.

METHODS

We included 198 patients admitted to Korea University Anam Hospital between 2006 and 2014 for obstructive colon cancer, of whom 98 underwent SEMS placement as a bridge to surgery and 100 underwent direct surgery without stenting. The clinicopathologic characteristics, overall survival, and disease-free survival were compared.

RESULTS

There were no significant differences in long-term oncologic outcomes between the two groups. The median follow-up durations were 61.55 and 58.64 months in the SEMS and DS groups, respectively. There were also no significant differences in the 5-year OS (77.4% vs. 74.2%, p = 0.691) and 5-year DFS (61.7% vs. 71.0%, p = 0.194) rates between the groups. However, the DS group had significantly more early postoperative complications (p = 0.002).

CONCLUSIONS

Colonic SEMS deployment as a bridge to surgery did not negatively affect long-term oncologic outcomes when compared with DS. In addition, colonic stenting decreased early postoperative complications and reduced the time for patients to return to normal daily activities.

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.

Perineural invasion is increased in patients receiving colonic stenting as a bridge to surgery: a systematic review and meta-analysis

BACKGROUND

In recent years, there has been growing concern about the potential association of stent placement as a bridge to surgery in malignant colon obstruction and some anatomopathological findings that could lead to worsening long-term cancer outcomes, such as perineural, vascular and lymphatic invasion. The aim of the present review was to assess the pathological changes found in surgical specimens after stent placement for obstructing colon cancer vs. emergency surgery, and the impact of perineural invasion on survival rates METHODS: MEDLINE, Cochrane Library, Ovid and ISRCTN Registry were searched, with no restrictions. We performed four meta-analyses to estimate the pooled effect sizes using a random effect model. The outcomes were perineural, vascular and lymphatic invasion rates, and 5-year overall survival rate in patients with obstructive colon cancer, depending on the presence or absence of perineural invasion.

RESULTS

Ten studies with a total of 1273 patients were included in the meta-analysis. We found that patients in the stent group had a significantly higher risk of perineural (OR 1.98, 95% CI 1.22-3.21; p = 0.006) and lymphatic invasion (OR 1.45, 95% CI 1.10-1.90; p = 0.008). Furthermore, patients with positive perineural invasion had almost twice the risk of dying compared to those with no perineural invasion (HR 1.92, 95% CI 1.22-3.02; p = 0.005).

CONCLUSIONS

Stent placement as a bridge to surgery in colorectal cancer patients modifies the pathological characteristics such as perineural and lymphatic invasion, and this may worsen the long-term prognosis of patients. The presence of perineural infiltration in obstructed colon cancer decreases the long-term survival of patients.