Vertical tumor margin of endoscopic resection for T1 colorectal carcinoma affects the prognosis of patients undergoing additional surgery

Procedural outcomes of a novel underwater injection endoscopic mucosal resection technique for colorectal polyps ≥10 mm

It is uncertain whether underwater endoscopic mucosal resection (UEMR) enables resection of the submucosal tissue with sufficient margins for T1 colorectal cancer (CRC) because UEMR forgoes submucosal injection. Therefore, we developed a novel "underwater injection EMR" (UIEMR) method that combines submucosal injection with UEMR to obtain an adequate vertical margin.We retrospectively analyzed procedure-related outcomes of 135 consecutive lesions from patients who underwent UIEMR for ≥10-mm nonpedunculated colorectal polyps (median size 15 mm). The outcomes included the en bloc, R0, RX, and R1 resection rates, and adverse events. Additionally, the vertical margin distance of seven T1 CRCs was evaluated.En bloc resection was achieved in 127 lesions (94.1%). R0 and RX resections were observed in 92 (68.1%) and 42 lesions (31.1%), respectively, while R1 resection was seen in only one lesion (0.7%). There were two cases with adverse events (1.5%), both delayed bleeding. In T1 CRCs, all seven cases had free vertical margins, and the median vertical margin distance was 1140 µm (range 731-1570 µm).UIEMR safely demonstrated high success rates for en bloc resection, and potentially ensures a sufficient vertical margin. This technique might be an option, particularly for relatively small lesions concerning for T1 CRC, and deserves further study.

Clinical usefulness of hybrid endoscopic submucosal dissection for T1b colorectal carcinomas ≤20 mm to ensure adequate vertical margins

Objective

To evaluate endoscopic resection strategies for cT1b colorectal carcinomas (CRCs) ≤20 mm to determine strategies that enable adequate vertical margins (VMs).

Methods

We enrolled 128 consecutive patients with cT1b colorectal carcinomas ≤20 mm resected by endoscopic mucosal resection or hybrid endoscopic submucosal dissection (ESD). Tumor lifting conditions after submucosal injection were classified into type A (lifting, soft dome-like), type B (lifting, hard trapezoid-like), and non-lifting (positive non-lifting sign). Predictors of positive VMs (VM 1) and adequate VMs were identified.

Results

All non-lifting tumors were resected by hybrid ESD and VMs were ≥500 µm. Vertical margin 1 tumors were only found in the endoscopic mucosal resection group, in which, the proportion of type B tumors with VM 1 was significantly higher than that of tumors with negative VMs (p < 0.01). Type A tumors showed no significant between-group differences. Among type B tumors, the proportion of VMs ≥500 µm was significantly higher (p < 0.01) and the VM distance was significantly longer (p < 0.01) in the hybrid ESD group than in the endoscopic mucosal resection group.

Conclusions

Hybrid ESD can be selected for type B tumors to ensure adequate VMs.

Enhanced diagnostic accuracy of SINE-EUS compared to standard EUS in early colorectal cancer: a self-controlled study

PURPOSE

This study compared the diagnostic performance of standard endoscopic ultrasound (EUS) and submucosal injection of normal saline and epinephrine-enhanced EUS (SINE-EUS) in detecting early colorectal cancer (CRC), emphasizing accuracy, sensitivity, and specificity.

METHODS

The self-controlled study was conducted with 115 patients diagnosed with early CRC through optical enhancement (OE) magnified endoscopy. Among them, 104 patients underwent sequential diagnostic procedures, starting with standard EUS and followed by SINE-EUS. Pathological findings were used as the reference standard. Statistical analyses assessed the diagnostic metrics and identified factors influencing accuracy.

RESULTS

Among 104 patients, 82 were pathologically diagnosed with early CRC (63 cases of Tis/T1a and 19 cases of T1b). Standard EUS showed a sensitivity of 68.3%, specificity of 52.6%, and overall accuracy of 64.6%. In contrast, SINE-EUS significantly improved sensitivity (85.7%), specificity (68.4%), and overall accuracy (81.7%) (P < 0.0167). Risk factors such as ulceration were identified as independent predictors of reduced diagnostic accuracy.

CONCLUSIONS

SINE-EUS outperforms standard EUS in diagnosing early CRC, particularly in terms of sensitivity and overall accuracy. This technique is reliable for clinical application, although limitations remain in improving specificity for deeper lesions.

Risk Factors for Perforation in Endoscopic Treatment for Early Colorectal Cancer: A Nationwide ENTER-K Study

Background/Aims

Early colorectal cancer (ECC) is commonly resected endoscopically. Perforation is a devastating complication of endoscopic resection. We aimed to identify the characteristics and predictive risk factors for perforation related to endoscopic resection of ECC.

Methods

This nationwide retrospective multicenter study included patients with ECC who underwent endoscopic resection. We investigated the demographics, endoscopic findings at the time of treatment, and histopathological characteristics of the resected specimens. Logistic regression analysis was used to investigate the clinical factors associated with procedure-related perforations. Survival analysis was conducted to assess the impact of perforation on the overall survival of patients with ECC.

Results

This study included 965 participants with a mean age of 63.4 years. The most common endoscopic treatment was conventional endoscopic mucosal resection (n=573, 59.4%), followed by conventional endoscopic submucosal dissection (n=259, 26.8%). Thirty-three patients (3.4%) experienced perforations, most of which were managed endoscopically (n=23/33, 69.7%). Patients who undergo endoscopic submucosal dissection-hybrid and precut endoscopic mucosal resection have a higher risk of perforation than those who undergo conventional endoscopic mucosal resection (odds ratio, 78.65 and 39.72, p<0.05). Procedure-related perforations were not associated with patient survival.

Conclusions

Perforation after endoscopic resection had no significant impact on the prognosis of ECC. The type of endoscopic resection was a crucial predictor of perforation. Large-scale prospective studies are needed to further investigate endoscopic resection of ECC.

Long-Term Outcomes of Additional Surgery After Endoscopic Resection Versus Primary Surgery for T1 Colorectal Cancer

INTRODUCTION

There is considerable concern about whether endoscopic resection (ER) before additional surgery (AS) for T1 colorectal cancer (CRC) has oncologically potential adverse effects. Therefore, the aim of this study was to compare the long-term outcomes, including overall survival (OS), of patients treated with AS after ER vs primary surgery (PS) for T1 CRC using a propensity score-matched analysis from a large observational study.

METHODS

This study investigated 6,105 patients with T1 CRC treated with either ER or surgical resection between 2009 and 2016 at 27 high-volume Japanese institutions, with those undergoing surgery alone included in the PS group and those undergoing AS after ER included in the AS group. Propensity score matching was used for long-term outcomes of mortality and recurrence analysis.

RESULTS

After propensity score matching, 1,219 of 2,438 patients were identified in each group. The 5-year OS rates in the AS and PS groups were 97.1% and 96.0%, respectively (hazard ratio: 0.72, 95% confidence interval: 0.49-1.08), indicating the noninferiority of the AS group. Moreover, 32 patients (2.6%) in the AS group and 24 (2.0%) in the PS group had recurrences, with no significant difference between the 2 groups (odds ratio: 1.34, 95% confidence interval: 0.76-2.40, P = 0.344).

DISCUSSION

ER before AS for T1 CRC had no adverse effect on patients' long-term outcomes, including the 5-year OS rate. ER is a viable first-line treatment option for endoscopically resectable T1 CRC.

Vertical margin distance in T1 colorectal carcinoma resected by endoscopic submucosal dissection affects prognosis after additional surgery

PURPOSE : A vertical margin (VM) distance of < 500 µm is a risk factor for recurrence in patients with T1 colorectal carcinoma (CRC) resected by endoscopy. We aimed to determine the effects of the VM distance on the recurrence and prognosis of T1 CRC.

METHODS

We enrolled 168 patients with T1 CRC who underwent additional surgery after endoscopic submucosal dissection (ESD) at multiple centers between 2008 and 2016. None of the patients were followed up for < 5 years. The enrolled 168 patients were classified into patients with VM distance of < 500 µm including positive VM (n = 72 [43%], VM distance < 500 µm group) and patients with VM distance of ≥ 500 µm (n = 96 [57%], VM distance ≥ 500 µm group). The clinicopathological features, recurrence rates, and prognoses were compared between the groups using propensity-score matching (PSM).

RESULTS

Tumors recurred in eight of the 168 patients (5%) with VM distance < 500 µm. After PSM, the rate of overall recurrence and local recurrence in the VM distance < 500 µm group were significantly higher than those in the VM distance ≥ 500 µm group. The 5-year recurrence-free survival rate was significantly higher in the VM distance ≥ 500 µm group than that in VM distance < 500 µm group after PSM (100% vs. 89%, p < 0.012).

CONCLUSIONS

Complete en bloc resection of T1 CRC via ESD must include a sufficient amount of SM to reduce the risk of metastasis and recurrence after additional surgery.

[Prognosis Analysis of Additional Surgical Treatment for High-Risk T1 Colorectal Cancer Patients After Endoscopic Resection]

Objective

To analyze the effect of additional surgery on the survival and prognosis of high-risk T1 colorectal cancer patients who have undergone endoscopic resection.

Methods

The clinical data of patients with high-risk T1 colorectal cancer were retrospectively collected. The patients were divided into the endoscopic resection (ER) plus additional surgical resection (SR) group, or the ER+SR group, and the ER group according to whether additional SR were performed after ER. Baseline data of the patients and information on the location, size, and postoperative pathology of the lesions were collected. Patient survival-related information was obtained through the medical record system and patient follow-up. The primary outcome indicators were the overall survival and the colorectal cancer-specific survival. Univariate Cox regression analysis was used to screen survival-related risk factors and hazard ratio (HR) was calculated. Multivariate Cox regression analysis was used to analyze the independent influencing factors.

Results

The data of 109 patients with T1 high-risk colorectal cancer were collected, with 52 patients in the ER group and 57 patients in the ER+SR group. The mean age of patients in the ER group was higher than that in the ER+SR group (65.21 years old vs. 60.54 years old, P=0.035), and the median endoscopic measurement of the size of lesions in the ER group was slightly lower than that in the ER+SR group (2.00 cm vs. 2.50 cm, P=0.026). The median follow-up time was 30.00 months, with the maximum follow-up time being 119 months, in the ER+SR group and there were 4 patients deaths, including one colorectal cancer-related death. Whereas the median follow-up time in the ER group was 28.50 months, with the maximum follow-up time being 78.00 months, and there were 4 patient deaths, including one caused by colorectal cancer. The overall 5-year cumulative survival rates in the ER+SR group and the ER group were 94.44% and 81.65%, respectively, and the cancer-specific 5-year cumulative survival rates in the ER+SR group and the ER group were 97.18% and 98.06%, respectively. The Kaplan-Meier analysis showed no significant difference in the overall cumulative survival or cancer-specific cumulative survival between the ER+SR and the ER groups. Univariate Cox regression analysis showed that age and the number of reviews were the risk factors of overall survival (HR=1.16 and HR=0.27, respectively), with age identified as an independent risk factor of overall survival in the multivariate Cox regression analysis (HR=1.10, P=0.045).

Conclusion

For T1 colorectal cancer patients with high risk factors after ER, factors such as patient age and their personal treatment decisions should not be overlooked. In clinical practice, additional caution should be exercised in decision-making concerning additional surgery.

Weighing the benefits of lymphadenectomy in early-stage colorectal cancer

Recent advancements in endoscopic procedures have resulted in a growing diagnosis of early colorectal cancer (CRC) cases, where classical en bloc lymph node (LN) dissection is not performed and treatment is terminated with the removal of the main cancer lesion by endoscopy without pathologic LN staging. Although many studies report noninferior outcomes of endoscopic resection in comparison to surgical resection, a cautious approach to completing treatment with endoscopic resection alone is recommended because LN metastases may be present even in early-stage CRC. In most countries, including the United States, Europe, and South Korea, the guidelines for additional surgery after endoscopic resection are very similar. If LN metastasis is suspected, even in T1 stage or lower lesions, further surgery is an essential treatment modality, but confirmation of the presence of LN metastasis is perhaps the most difficult part of this process. Another paradoxical recent trend is the expansion of more extensive and complete surgical lymphadenectomy for CRC. The success rate of surgery has improved dramatically over the past decade with the introduction of surgical devices and minimally invasive surgery, and the associated risks have been significantly reduced. While the burden of surgery on patients is understandable, the indications for surgery in early colon cancer need to be carefully reviewed to improve cure rates. In this process, we believe that an integrated decision-making process with surgeons, radiologists, and pathologists, in addition to the opinions of endoscopists, will be an important process to improve the cure rate.