Intraluminal exfoliated cancer cells and effectiveness of bowel ligatures during sigmoidectomy for sigmoid colon cancer

Implantation of sigmoid colon cancer into the endoscopic resection site of intramucosal rectal cancer: A case report

A 70-year-old woman was diagnosed with intramucosal rectal cancer and advanced sigmoid colon cancer at the same time. First, the intramucosal rectal cancer was curatively resected by endoscopic submucosal dissection, and surgery was subsequently performed for sigmoid colon cancer. After 20 months, a follow-up colonoscopy revealed a tumor growth at the ulcer scar of the endoscopic submucosal dissection. Histological findings and KRAS mutation analysis suggested implantation of sigmoid colon cancer to the post-endoscopic submucosal dissection site of intramucosal rectal cancer.

Implantation metastasis from sigmoid colon cancer to rectal anastomosis proved by whole exome sequencing and lineage inference for cancer heterogeneity and evolution analysis: Case report and literature review

It was estimated that 70% of patients with colorectal cancer were found to have viable exfoliated malignant cells in adjacent intestinal lumen. Exfoliated malignant cells had been reported to implant on raw surfaces, such as polypectomy site, anal fissure, anal fistula, hemorrhoidectomy wound, and anastomotic suture line. Tumors at anastomosis could be classified into four groups: local recurrence, local manifestation of widespread metastasis, metachronous carcinogenesis, and implantation metastasis. However, all of the previous studies only reported the phenomena of implantation metastasis at anastomosis. No study had proved the origin of anastomotic metastasis by genomic analysis. In this study, a 43-year-old woman presented with persistent hematochezia was diagnosed as having severe mixed hemorrhoids. She was treated by procedure for prolapse and hemorrhoids (PPH), without receiving preoperative colonoscopy. Two months later, she was found to have sigmoid colon cancer by colonoscopy due to continuous hematochezia and received radical sigmoidectomy. Postoperative histological examination confirmed the lesion to be a moderately differentiated adenocarcinoma (pT3N1M0). Six months later, she presented with hematochezia again and colonoscopy revealed two tumors at the rectal anastomosis of PPH. Both tumors were confirmed to be moderately differentiated adenocarcinoma without lymph node and distant metastasis and were finally removed by transanal endoscopic microsurgery (TEM). Pathological examination, whole exome sequencing (WES), and Lineage Inference for Cancer Heterogeneity and Evolution (LICHeE) analysis demonstrated that the two tumors at the rectal anastomosis were probably implantation metastases arising from the previous sigmoid colon cancer. This is the first study to prove implantation metastasis from colon cancer to a distal anastomosis by WES and LICHeE analysis. Therefore, it is recommended to rule out colorectal cancer in proximal large bowel before performing surgery with a rectal anastomosis, such as PPH and anterior resection. For patients with a suspected implanted tumor, WES and LICHeE could be used to differentiate implantation metastasis from metachronous carcinogenesis.

Exfoliated cancer cells during intersphincteric resection for very low rectal cancer

PURPOSE

To investigate the frequency of exfoliated cancer cells and the efficacy of rectal washout during intersphincteric resection (ISR) in patients not receiving chemoradiotherapy (CRT) for very low rectal cancer.

METHOD

The subjects of this prospective study were 16 consecutive patients who underwent ISR without CRT for very low rectal cancer. Brushing cytology of the posterior anorectal wall was performed twice in each step of the ISR procedure and the samples were sent for blind cytological examination to identify exfoliated cancer cells.

RESULTS

Exfoliated cancer cells were identified in 9 of 13 patients (69%) preoperatively. The number of cancer cells identified after abdominal total mesorectal dissection decreased significantly from 94% (15/16) to 25% (4/16) after transanal irrigation with 2000 mL saline (p < 0.001). No cancer cells were identified after swabbing the anal wall following transanal dissection with purse-string closure of the distal stump. No suture-line recurrence was found during a median follow-up duration of 6 years.

CONCLUSION

Exfoliated cancer cells, confirmed in 94% of patients after total mesorectal excision, could be eliminated by performing rectal irrigation after clamping the rectum proximal to the tumor and swabbing the anorectal wall during ISR.

Short- and long-term outcomes of robotic surgery for rectal cancer: a single-center retrospective cohort study

PURPOSE

This study aimed to clarify the short- and long-term outcomes of robotic surgery with or without lateral lymph node dissection (LLND) for rectal cancer at Fujita Health University Hospital, Aichi, Japan, during a self-pay period.

METHODS

We retrospectively evaluated 115 consecutive patients who underwent robotic surgery for rectal cancer between September 2009 and March 2018, with a median follow-up period of 48 months. Total mesorectal excision was completed by two certified surgeons using a da Vinci S, Si, or Xi Surgical System with an entirely robotic single-docking technique. The surgical and pathological outcomes, morbidity, and oncological results were examined.

RESULTS

Lateral lymph node dissection was performed in 26 patients (22.6%). Neither conversion to open surgery nor perioperative blood transfusion occurred. Ten patients (8.7%) experienced Clavien-Dindo grade III postoperative complications. Pathologically, both the distal and radial margins were negative in all cases. The 5-year relapse-free survival rates for stages I, II, III, and IV were 93.5%, 100%, 83.8%, and not reached, respectively.

CONCLUSIONS

Even in the period before coverage by the health insurance system, robotic surgery for rectal cancer performed by experienced surgeons was safe and technically feasible, with favorable perioperative results and long-term oncological outcomes, including rates of the relapse-free survival.

Synchronous polypectomy during endoscopic diagnosis of colorectal cancer - is the risk of tumour implantation at the polypectomy site significant?

Background

Synchronous polypectomy in colonic malignancies is contentious due to the perceived risks of tumour implantation at polypectomy sites (PS). We assess the risks of tumour implantation after synchronous polypectomy.

Methods

An analysis of all endoscopies for cancer that were accompanied by synchronous polypectomies from 2005 to 2009 was performed. The incidence of metachronous colorectal cancers located at the same segment of a previous PS was the surrogate for tumour implantation. Data on patient demographics, tumour and polyp location(s) and follow-up outcomes were extracted. The rate of metachronous lesions at the same segment of a previous PS between patients who had all synchronous PS resected (Group A) and patients with PS left in-situ (Group B) were compared.

Results

Two hundred and eighty-four patients had synchronous polypectomy performed during their initial endoscopy for cancer. Three patients were lost to follow-up and, in the remaining 281 patients, 87 (31.0%) were in Group A while 194 (69%) were in Group B. Median age, gender, tumour location, tumour stage, and pathological characteristics were similar between both groups. 2 (0.7%) patients developed local recurrences. Six (2.1%) patients developed metachronous lesions, four of which were located at the same segment where synchronous polypectomy was previously performed. The rates of metachronous lesions at the PS in groups A and B were similar at 1.1% (1/87) and 1.5% (3/194), respectively (p = 0.795).

Conclusion

Malignant implantation after synchronous polypectomy in the setting of a newly diagnosed cancer remains unproven. Even if tumor implantation did occur, the incidence is likely low.

Anal metastasis from rectal adenocarcinoma

The metastasis of rectal cancer to the anus is rare. Here, we report a case of advanced rectal cancer, which had a diffuse venous invasion with anal metastasis and multiple lymph node and liver metastases. The patient was a 72-year-old woman who complained of perianal pain and fresh blood in the stools for 6 months. She had neither history of fistula-in-ano nor anal surgery. Digital examination revealed a 2-cm tumor at the 7 o'clock position, and the barium enema and colonoscopy confirmed advanced rectal cancer. Abdominal computed tomography revealed thickness of the upper rectum wall, right inguinal lymph node of 10 mm and multiple liver metastases. Laparoscopically assisted anterior resection, anal tumor resection, and right inguinal lymph node resection were performed, and the histopathological examination of the resected primary and metastatic tumors confirmed similar findings of moderately differentiated adenocarcinoma, suggestive of metastasis of the rectal cancer to the anal region. In the next procedure, she had the liver lesions resected. This case suggested the importance of the careful examination of the anus during colonoscopy, or digital examination for the detection of anal metastasis.

Positive detection of exfoliated colon cancer cells on linear stapler cartridges was associated with depth of tumor invasion and preoperative bowel preparation in colon cancer

BACKGROUND

The aim of this study was to investigate exfoliated cancer cells (ECCs) on linear stapler cartridges used for anastomotic sites in colon cancer.

METHODS

We prospectively analyzed ECCs on linear stapler cartridges used for anastomosis in 100 colon cancer patients who underwent colectomy. Having completed the functional end-to-end anastomosis, the linear stapler cartridges were irrigated with saline, which was collected for cytological examination and cytological diagnoses were made by board-certified pathologists based on Papanicolaou staining.

RESULTS

The detection rate of ECCs on the linear stapler cartridges was 20 %. Positive detection of ECCs was significantly associated with depth of tumor invasion (p = 0.012) and preoperative bowel preparation (p = 0.003). There were no marked differences between ECC-positive and ECC-negative groups in terms of the operation methods, tumor location, histopathological classification, and surgical margins.

CONCLUSIONS

Since ECCs were identified on the cartridge of the linear stapler used for anastomosis, preoperative mechanical bowel preparation using polyethylene glycol solution and cleansing at anastomotic sites using tumoricidal agents before anastomosis may be necessary to decrease ECCs in advanced colon cancer.

Positive detection of exfoliated colon cancer cells on linear stapler cartridges was associated with depth of tumor invasion and preoperative bowel preparation in colon cancer

Background

The aim of this study was to investigate exfoliated cancer cells (ECCs) on linear stapler cartridges used for anastomotic sites in colon cancer.

Methods

We prospectively analyzed ECCs on linear stapler cartridges used for anastomosis in 100 colon cancer patients who underwent colectomy. Having completed the functional end-to-end anastomosis, the linear stapler cartridges were irrigated with saline, which was collected for cytological examination and cytological diagnoses were made by board-certified pathologists based on Papanicolaou staining.

Results

The detection rate of ECCs on the linear stapler cartridges was 20 %. Positive detection of ECCs was significantly associated with depth of tumor invasion (p = 0.012) and preoperative bowel preparation (p = 0.003). There were no marked differences between ECC-positive and ECC-negative groups in terms of the operation methods, tumor location, histopathological classification, and surgical margins.

Conclusions

Since ECCs were identified on the cartridge of the linear stapler used for anastomosis, preoperative mechanical bowel preparation using polyethylene glycol solution and cleansing at anastomotic sites using tumoricidal agents before anastomosis may be necessary to decrease ECCs in advanced colon cancer.

Endoscopic excision of synchronous large bowel polyps in the presence of colorectal carcinoma: is the fear of malignant cell implantation justified? A systematic review of the literature

AIM

A systematic review of the literature was performed to establish evidence to support the practice that in the presence of a colonoscopically diagnosed colorectal cancer immediate endoscopic excision of synchronous polyps should not be performed due to the risk of malignant cell implantation at the polypectomy site.

METHOD

A systematic literature search was performed using Medline, Embase and the Cochrane Central Register of Controlled Trials to identify studies comparing the rate of implantation of colorectal cancer cells in normal and damaged colonic mucosa and reports of colorectal cancer cells seeding into sites of damaged mucosa after polypectomy.

RESULTS

No randomized controlled trials were identified. Three studies involving mammalian models of colonic mucosal damage were included. Pooling relevant results revealed that out of 59 exposed mammals only one developed tumour cell implantation at a site of colonic mucosal damage. This equates to a mammalian in vivo experimental risk of malignant cell implantation of 1.6%.

CONCLUSION

The topic of colorectal cancer seeding following endoscopic procedures has received little attention. This review suggests that in the presence of a proximal colonic carcinoma there is a negligible risk of malignant implantation if a more distal polyp is endoscopically excised.