Introduction

Cold snare polypectomy (CSP) for polyps 10-14 mm is unsatisfactory, with higher rates of unclear/positive histologic margins compared to small polyps,¹ which is similar for CSP with submucosal injection.² Therefore, hot snare polypectomy (HSP) or endoscopic mucosal resection (EMR) has been widely performed for polyps measuring ≥10 mm.³ However, these procedures often cause adverse events such as delayed bleeding and perforation due to deep thermal injury related to the use of electrocautery.⁴ A recent large-scale study reported a low incidence (0.9%) of invasive cancer in 10-19 mm colorectal polyps.⁵ Therefore, the development of less invasive therapeutic options for this size category is demanding.
Thus, we have developed HSP with low power pure-cut current (LPPC-HSP), a polypectomy technique with low power, low voltage, and no coagulation current (UMIN Clinical Trials Registry; UMIN000037678). This method uses pure-cut current and reduces the power of electrocautery, expecting less deep thermal damage compared with conventional HSP with blend or coagulation current, resulting in a lower risk of perforation and bleeding. This study aimed to evaluate the efficacy and safety of LPPC-HSP for colorectal polyps 10 to 14 mm, compared with conventional EMR.

Aims & Methods

In this multicenter, retrospective, observational study, records of patients who underwent EMR or LPPC-HSP for nonpedunculated colorectal polyps 10 to 14 mm at two Japanese institutions between January 2021 and March 2022 were evaluated consecutively. EMR was performed with blend cut current (Endocut Q; effect 3, time interval 2, time duration 2), while LPPC-HSP with a low power pure-cut current (Autocut; effect 1, 10 W in VIO300D or Autocut; effect 0.4 [Pmax 13 W] in VIO3). We analyzed the treatment outcomes of the two techniques using propensity score matching to reduce selection bias. The following variables expected to affect treatment outcomes were selected: age, sex, polyp size, morphology, lesion location, endoscopists (experienced endoscopists or gastrointestinal fellows), and antithrombotic agents. R0 resection was defined as en bloc resection with histologically tumor-free margins.

Results

We retrospectively enrolled 203 EMR (168 patients, 203 lesions) and 208 LPPC-HSP (169 patients, 208 lesions) cases. After propensity score matching, the baseline characteristics between the groups were comparable, with 131 pairs. The en bloc and R0 resection rates were not significantly different between EMR and LPPC-HSP groups (93.9% vs. 96.9%, P=0.38; 90.8% vs. 91.6%, P=1.00). The vertical margin was negative in all lesions except one in the EMR group. Immediate bleeding requiring hemostasis was observed in 10.7% of cases in the EMR group versus 2.3% in the LPPC-HSP group (P=0.010). The rates of delayed bleeding and perforation didn’t differ between the groups (0% vs. 0.8%, P=1.00; 0% vs. 0%).

Table 1. Baseline characteristics and treatment outcomes after propensity score matching
Baseline characteristics	EMR n=131	LPPC-HSP n=131	P value	standardized difference		Treatment outcomes	EMR n=131	LPPC-HSP n=131	P value
Age, years (interquartile range)	72 (67-76)	72 (68-78)	0.29	0.105		En bloc resection (%)	123 (93.9)	127 (96.9)	0.38
Male sex (%)	91 (70)	96 (73)	0.59	0.085		R0 resection (%)	119 (90.8)	120 (91.6)	1.00
Lesion size, mm (interquartile range)	10 (10-12)	10 (10-12)	0.93	0.017		Immediate bleeding (%)	14 (10.7)	3 (2.3)	0.01
Location right colon/left colon/rectum (%)	61 (47) / 53 (41) / 17 (13)	63 (48) / 53 (41) / 15 (12)	0.95	0.049		Delayed bleeding (%)	0 (0)	1 (0.8)	1.00
Morphology 0-Is/0-IIa (%)	89 (68) / 42 (32)	87 (66) / 44 (34)	0.90	0.033		Perforation (%)	0 (0)	0 (0)	N/A
Antithrombotic agents (%)	24 (18)	35 (27)	0.14	0.202
Gastrointestinal fellows performed (%)	42 (32)	44 (34)	0.90	0.033

Conclusion

LPPC-HSP showed treatment outcomes comparable to conventional EMR, with fewer adverse events. These results suggest that this technique is a safe and effective treatment for nonpedunculated colorectal polyps 10 to 14 mm.

References

1. Hirose R, Yoshida N, Murakami T, et al. Histopathological analysis of cold snare polypectomy and its indication for colorectal polyps 10-14 mm in diameter. Dig Endosc 2017;29:594-601.
2. Yabuuchi Y, Imai K, Hotta K, et al. Efficacy and safety of cold-snare endoscopic mucosal resection for colorectal adenomas 10 to 14 mm in size: a prospective observational study. Gastrointest Endosc 2020;92:1239-1246.
3. Ferlitsch M, Moss A, Hassan C, et al. Colorectal polypectomy and endoscopic mucosal resection (EMR): European Society of Gastrointestinal Endoscopy (ESGE) Clinical Guideline. Endoscopy 2017;49:270-297.
4. Oka S, Tanaka S, Kanao H, et al. Current status in the occurrence of postoperative bleeding, perforation and residual/local recurrence during colonoscopic treatment in Japan. Dig Endosc 2010;22:376-380.
5. Parsa N, Ponugoti P, Broadley H, et al. Risk of cancer in 10 - 19 mm endoscopically detected colorectal lesions. Endoscopy 2019;51:452-457.

Disclosure

Authors declare no Conflict of Interests for this study.

Introduction

Familial adenomatous polyposis (FAP) is an inherited colorectal cancer syndrome characterized by the development of numerous adenomatous polyps in the colon and rectum, with prophylactic colectomy being the standard treatment to prevent disease progression. Recently, endoscopic intensive downstaging polypectomy (IDP) has attracted attention as a novel disease management strategy, particularly for patients with non-dense FAP who refuse or delay surgery. Since IDP requires the resection of numerous polyps, simpler and safer techniques such as hot snare polypectomy (HSP), cold snare polypectomy (CSP), and hot biopsy (HB) are commonly used. However, the effectiveness of these techniques for the treatment of small adenomas in the context of IDP has not been fully evaluated.

Aims & Methods

This study aimed to evaluate the safety and efficacy of CSP compared with HSP and HB in patients with FAP undergoing IDP. This retrospective study included patients with FAP who underwent IDP using only CSP, HSP, or HB at Hiroshima University Hospital between September 2012 and March 2024. Patients were divided into two groups: the CSP group, treated with CSP from October 2022 onward, and the HOT group, treated with HSP and HB between 2012 and September 2022. The primary endpoints were the incidence of adverse events and the treatment duration per polyp. Secondary endpoints included the incidence of immediate and delayed bleeding, perforation, total treatment duration per session, number of polyps removed per procedure, R0 resection rate, and the rate of missed polyps ≥10 mm.

Results

Variables	Total (n=185)	CSP (n=46)	HOT (n=139)	p-value
Treatment duration per procedure (min)	45.9 (22.1)	51.1 (23.2)	44.3 (21.7)	0.06
Polyps removed per procedure	51.6 (52.1)	80.5 (56.8)	42.1 (46.9)	< 0.01
Treatment duration per lesion (min)	1.7 (1.4)	1.3 (1.4)	1.8 (1.3)	0.01
Maximum tumor size per procedure (mm)	5.2 (2.4)	6.0 (2.5)	4.9 (2.4)	< 0.01
Overall adverse events (n (%)) Immediate bleeding (n (%)) Delayed bleeding (n (%)) Perforation (n (%))	14 (7.6) 10 (5.4) 2 (1.1) 2 (1.1)	0 (0) 0 (0) 0 (0) 0 (0)	14 (10.1) 10 (7.2) 2 (1.1) 2 (1.1)	0.03 0.06 0.41 0.41

During the study period, 46 treatment sessions were performed in 24 patients in the CSP group, resulting in the removal of a total of 3,689 polyps. In contrast, 139 treatment sessions were performed in 27 patients in the HOT group, with a total of 5,912 polyps removed. The average number of polyps removed per session was significantly higher in the CSP group (80.5 polyps) than in the HOT group (42.1 polyps) (p < 0.01). Additionally, the treatment duration per polyp was significantly shorter in the CSP group (1.3 minutes) than in the HOT group (1.8 minutes) (p = 0.01). The total treatment duration per session was slightly longer in the CSP group (51.1 minutes) compared to the HOT group (44.3 minutes), although the difference was not statistically significant (p = 0.06). The maximum polyp size was significantly larger in the CSP group (6.0 mm) than in the HOT group (4.91 mm) (p < 0.01). The overall incidence of adverse events was significantly lower in the CSP group. Immediate bleeding occurred in 10 cases (7.2%) in the HOT group but was not observed in the CSP group. Delayed bleeding and perforation were also observed only in the HOT group; however, there were no statistically significant differences between the groups.

Conclusion

This study demonstrated that CSP is a safe and effective option for intensive polyp reduction in patients with FAP. Compared with HSP and HB, CSP enabled the removal of more polyps in a shorter duration and reduced the risk of adverse events.

Introduction

Over the world, fecal occult blood testing (FOBT) is used as a colorectal cancer (CRC) screening method for middle age and older age, but there are problems such as sensitivity/specificity issues, low participation rates in primary and secondary screenings, and that the incidence/mortality rates of CRC are still high. Fusobacterium nucleatum (Fn) has been reported to be frequently detected in the feces of CRC patients in recent years, and it has been reported that screening sensitivity can be increased by combining it with Fn PCR testing. However, due to the cost and technical complexity of PCR, it has not yet been widely used in clinical practice. In this study, we developed a simple method using ELISA to measure antibodies against FadA expressed by Fn and evaluated its usefulness.

Aims & Methods

We evaluated FOBT, Fn PCR quantification, and Fn (ELISA) in 41 individuals diagnosed with CRC from April 2020 to December 2022 and 41 healthy volunteers without CRC. Subgroup analysis was also performed in CRC patients at each stage.

Results

The correlation coefficient between Fn PCR quantification and Fn (ELISA) was good at r=0.722, p<0.001. FOBT alone had a sensitivity of 61% and a specificity of 100%. In Fn ELISA, when cut off#1 was set to maximize the AUC in ROC, the sensitivity and specificity were 76% and 78%, respectively, and when combined with FOBT, the sensitivity was 90% and the specificity was 78%. In screening, high specificity is required, so we set cut off#2 Fn ELISA to achieve a specificity of 93% and performed analysis. When combined with FOBT, the sensitivity was 73% and the specificity was 93%. When targeting advanced cancer of stage II or higher, the sensitivity by combining FOBT and Fn ELISA was 100% at cut off#1 and 79% at cut off#2, while for early cancer, the sensitivity was 76% at cut off#1 and 59% at cut off#2, both of which were better than the sensitivity of FOBT alone.

Conclusion

By combining Fn measurement using ELISA with FOBT, it was possible to increase the diagnostic sensitivity and reduce false negatives compared to FOBT alone. There are challenges such as setting appropriate cut-off values for use in screening, but measuring Fn in addition to FOBT may improve screening accuracy and increase the participation rate in secondary screening, and in the future, we would like to evaluate its effectiveness even in populations with low prior probability of screening participation.

Introduction

Colorectal cancer (CRC) is a global health problem with high incidence and mortality rates. Although the incidence has decreased with the use of screening tests, the mortality rate is approximately 1,6 – 2,0 % per year. Recent studies have shown a steady increase in the incidence of early onset (<50 years) CRC compared to that of patients >50 years of age. Early-onset CRC cancer is reported to have a more progressive course and may have a genetic and epigenetic background. In this study, we aimed to investigate the disease characteristics and risk factors for colorectal cancer in patients <50 years old and compare with patients over 50 years of age.

Aims & Methods

Patients younger than 50 years, diagnosed with colorectal adenocarcinoma and followed in our hospitals' gastroenterology, oncology, or general surgery departments between January/2009 and June/2022 were included in this retrospective study. A total of 6102 patients’ files were examined. Among these, 1166 were under the age of 50, whilst 4936 were 50 years and older. Patients younger than 18 years, who had a previous history of CRC, a known familial CRC syndrome, who had synchronous tumors at the time of diagnosis or had in situ CRC were not included in the study. After applying the exclusion criteria, 989 patients were included in the under-50 age group. The comparison group consisted of 1009 patients randomly selected from a group of 4000 patients aged 50 years or older. Patients were divided into Group A (<50 years) and Group B (≥ 50 years) according to the age at diagnosis. Patients’ demographic characteristics, body mass index, history of cigarette smoking and alcohol use, presenting symptoms, history of H. pylori infection, co-morbidities and medications were recorded from the files. Tumour characteristics, localization, size, TNM stage, and treatment methods were also analyzed and the relationship with each other was examined comparatively.

Results

The results of 1998 patients included in the study are shown in Table 1. TNM stages and the duration of symptoms before the diagnosis were similar between the groups but the rate of stage 1 disease was higher in group B. The rates of metastatic disease and rectal cancer were higher in Group A, but statistically non-significant. Abdominal pain was significantly more frequent in Group A, while anemia was significantly more common in Group B. Patients in Group A had higher rates of IBD, family history of CRC, mucinous adenocarcinoma, poorly differentiated tumor, higher histological grade and higher microsatellite instability (MSI-H). Although perineural and lymphatic invasion rates were similar, vascular invasion was higher in group B.

Table1. Comparison of Patients in Group A and Group B

Variables	Group A (n)	Group B (n)	p value
Body Mass Index ≥30 kg/m2	110	198	p<0.01
Family history of CRC	137	130	p<0.05
History of Inflammatory Bowel Disease	16	7	p<0.01
Tumor grade-1	104	151	p<0.01
Mucinous adenocarcinoma	131	90	p<0.01
Poor differentiation	165	96	p<0.01
High histologic grade	116	65	p<0.01
Presence of vascular invasion	277	412	p<0.01
MSI-H	58	29	p<0.01

Conclusion

Our study revealed that Early-onset CRC is more frequently diagnosed at the metastatic stage, is characterized by a more common presence of mucinous cells, poorly differentiated histology, and microsatellite instability.