What is circumferential resection margin in rectal cancer?

What is circumferential resection margin in rectal cancer?

Circumferential resection margin (CRM) in rectal cancer has been defined as the non-peritonealized surface of a resection specimen created by dissection of the subperitoneal aspect at surgery. CRM involvement occurs at a rate ranging from 7.3 to 25%.

What does circumferential resection margin mean?

INTRODUCTION. Circumferential resection margin (CRM) is the closest distance between the radial resection margin and the tumor tissue by either direct tumor spread, areas of neural or vascular invasion, or the nearest involved lymph node.

Can an MRI show rectal cancer?

Typically, a rectal MRI scan is performed after it has already been proven by biopsy that the tumor is cancerous. It’s the most helpful imaging tool available to diagnose rectal cancer because of its ability to capture detailed pictures of the tissue layers within the rectal wall.

What are the margins for colon cancer?

It is therefore recommended that at least a 5-cm margin of normal bowel be obtained on either side of the tumor in order to minimize the possibility of an anastomotic recurrence.

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 CRM threatened?

Introduction It is recognised that following rectal cancer resection, a threatened or involved circumferential resection margin (CRM) is associated with increased local recurrence rates. However the significance of a pathological positive lymph node (LN) threatening or involving the CRM remains unclear.

What are positive surgical margins?

A positive surgical margin at prostatectomy is defined as tumor cells touching the inked edge of the specimen. This finding is reported in 8.8% to 42% of cases (median about 20%) in various studies.

Why is MRI used for rectal cancer?

MRI is the modality of choice for staging rectal cancer to assist surgeons in obtaining negative surgical margins. MRI facilitates the accurate assessment of mesorectal fascia and the sphincter complex for surgical planning.

What is a high anterior resection?

What is a high anterior resection? This operation aims to remove a segment of your bowel known as the sigmoid colon with or without the upper rectum including the blood supply and associated lymph glands.

What stage is well differentiated adenocarcinoma?

Low grade or grade I tumors are well-differentiated. This means that the tumor cells are organized and look more like normal tissue. High grade or grade III tumor cells are poorly differentiated.

What does deep margin positive mean?

The margin is described as positive or involved when the pathologist finds cancer cells at the edge of the tissue, suggesting that all of the cancer has not been removed.

What is a circumferential mass?

When the tumor occupied a single quadrant, that quadrant was defined as the location of tumor. If the mass was located in more than two quadrants, the location was defined as the quadrant with the deepest extent of tumor invasion. A circumferential tumor was defined as a tumor involving over 75% of the circumference.

What does it mean when margins are not clear?

A clear, negative, or clean margin means there are no cancer cells at the outer edge of tissue that was removed. A positive margin means that cancer cells come right out to the edge of the removed tissue and have ink on them.

What is a positive margin after prostatectomy?

What is an MRI with rectal protocol?

MRI protocol for rectal cancer is a group of MRI sequences put together for imaging staging of primary tumors of the rectum and assessment of response following neoadjuvant therapy. Modified versions of the protocol may also be used for the assessment of local recurrence.

Why it is called anterior resection?

Other terms used include low anterior resection (LAR), which classically refers to removal of the sigmoid colon and upper rectum and derives its name from the fact that the dissection is below the anterior reflection of the peritoneal lining.