surgery of colorectal cancer





anal verge         肛門縁

anastomosis      吻合

colorectal cancer            大腸癌

complication     合併症

diversion          迂回

laparoscopic resection  腹腔鏡下切除術

lymphatic          リンパ管

mesorectum     直腸間膜 

primary cancer              原発性癌

primary treatment        一次治療法

submucosa        粘膜下組織

subtotal colectomy        結腸亜全摘術

systemic treatment       全身治療

total mesorectal resection        直腸間膜全切除

transanal resection       経肛門切除



Resection is the primary treatment for patients with non-metastatic colorectal cancers. 



Patients with metastatic colorectal cancers may have surgery for radical treatment if some conditions are satisfied. 



Colonic cancers should be resected along with primary feeding arterial vessel and corresponding lymphatics so that no cancer cells remain.



At least 12 lymph nodes should be microscopically examined to accurately assure staging of colonic cancers.


Colon cancers that simultaneously occur may be resected individually or removed with subtotal colectomy, and tumors that invade adjacent structures should be removed as a whole.



Laparoscopic resection surgery conducted by an experienced surgeon is as effective as open resection surgery and can moderately shorten recovery time.



For lower rectal cancers, total mesorectal resection (whole removal of lymphovascular and fatty envelope surrounding the rectum) is endorsed.  In contrast, for upper rectal cancers, cancer-specific mesorectal resection (whole removal of the mesorectum 5 cm distal to the tumor) may be sufficient. 



Local transanal resection may be performed for low rectal cancers if it is believed to have minimal risk of lymphnodal invasion.



Local transanal resection may be performed in the cases including cancer stage is T1; size of cancer is less than 3 cm; cancer is well differentiated; cancer is located within 8 cm of the anal verge; no lymphovascular invasion; and area of cancer do not circumferentially occupy greater than one-third.


Until quite recently, patients with multiple primary colorectal cancers and unresectable metastases tend to have primary cancer resection regardless of whether or not they are symptomatic .



This practice may delay systemic treatment in patients who are more likely to die from their metastases before suffering complications from the large bowel cancers.



Recent studies indicate that stage IV patients with an asymptomatic primary colorectal cancer can safely start systemic therapy without undergoing surgery, with only a small chance of developing serious complications requiring urgent surgery.



Patients with primary rectal cancers may have a slightly higher risk of complications than those with colon cancers.



If obstructing cancers can be fully removed, they need to be resected and anastomosed. 



If an advanced colorectal cancer is locally confined and unresectable, diversion may be necessary.  If the cancer can be removed later, it may be resected and anastomosed. 


Acute obstruction of large bowel may be alleviated by endoscopic stenting.



If bowel perforation occurs, it should be resected and anastomosed with or without diversion, depending on degree of fecal contamination, general health condition of the patient, and so forth.