What is mesorectal fat?

The mesorectal fascia is a layer of connective tissue enclosing the perirectal fat that surrounds the rectum. It is an important anatomical structure in rectal cancer staging, as it forms the circumferential resection margin for the non-peritonealised portion of the rectum.

What does CRM positive mean?

CRM involvement was defined as a distance from the circumference margin of ≤1 mm. 9. Patients were divided into two groups: “CRM-positive group” (CRM ≤1 mm) and “CRM-negative group” (CRM >1 mm) according to the shortest distance between the CRM and the tumor (Fig. 1).

Is colon cancer treatable?

Cancer of the colon is a highly treatable and often curable disease when localized to the bowel. Surgery is the primary form of treatment and results in cure in approximately 50% of the patients.

Are mesorectal lymph nodes normal?

Conclusions: Our study confirmed that more than 30 lymph node units normally exist in the mesorectal area. In view of previous studies demonstrating advantages of increasing the number of lymph nodes evaluated, staging of rectal cancer might be improved by counting more than 12 lymph nodes per specimen.

What is CRM in colorectal surgery?

Circumferential resection margin (CRM) is a term used to denote the standard plane of excision of total mesorectal excision, used for resection of rectal cancers.

What is a circumferential tumor?

The circumferential extent of a tumor is one factor that represents the amount and invasion area of a rectal cancer. A circumferential extent of a tumor of 75% or more has been shown to be a risk factor for the intramural distal spread of rectal cancer.

What is a mesorectal node?

Mesorectal lymph nodes refers to lymph nodes that are present in the mesorectal fascia. Their assessment is important in the staging of colorectal tumors such as rectal cancer and anal cancer.

Where are the mesorectal lymph nodes?

There are few lymph nodes within the mesentery of the lower third of the rectum and relatively few in the right and left lateral portions of the mesorectum. We confirm that the majority of nodes are located in the proximal two-thirds of the posterior rectal mesentery.

Where are mesorectal lymph nodes?

What is mesorectal fascia?

The mesorectal fascia is a layer of connective tissue enclosing the peri-rectal fat that surrounds the rectum. It is not an anatomical termed recognized by the Terminologia Anatomica because it is mainly a surgical and radiological term for rectal cancer staging.

What is a D2 resection?

Definition of D2 lymphadenectomy is additional removal of a second tier of lymph nodes in the extraperigastric areas, which generally fall along branches of the celiac axis including the left gastric, splenic, common hepatic, and proper hepatic arteries.

What is r in TNM staging?

The R classification, an auxiliary classification within the TNM system, denotes the absence or presence of residual tumor after treatment and describes residual tumor as macroscopic or microscopic in amount.