What is an R1 resection in rectal cancer?

Circumferential resection margin involve- ment (R1) in rectal cancer is a well-established predic- tive factor for poor prognosis [1,2] with increased risk of both local recurrence and distant metastasis [2,3]. The significance of R1 or resection margin involvement is less well studied in colon cancer resection.

What is APR surgery for rectal cancer?

An abdominal perineal resection (APR) includes the resection of the sigmoid colon, rectum, and anus (figure 1), and the construction of a permanent end colostomy.

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%.

Where is the first place rectal cancer spreads?

Rectal cancer most often spreads to the liver. This happens in part because the blood supply from the large intestine, which includes the rectum, is connected to the liver through a large blood vessel.

How long does an APR surgery take?

Generally, abdominoperineal resection surgery takes about two to three hours. This timeframe can vary depending on your specific situation.

How is APR surgery performed?

During an APR, the entire rectal cancer, adjacent normal rectum, rectal sphincter or anus, and surrounding lymph nodes are removed through an incision in the lower abdomen and the perineum (the skin around the anus). Following removal of the cancer, the incision in the perineum is sewn shut.

What is R0 R1 R2 resection?

R0 corresponds to resection for cure or complete remission. R1 to microscopic residual tumor, R2 to macroscopic residual tumor. The R classification takes into account clinical and pathological findings. A reliable classification requires the pathological examination of resection margins.

What is the circumferential resection margin?

Circumferential resection margin(CRM) is the closest distance from the deepest of tumor invasion to the surgical margin of mesentery. It has been well known that CRM has significant impact on the prognosis and treatment of rectal cancer.

How long does it take for rectal cancer to metastasize?

They don’t need to acquire any new genetic mutations to become metastatic. The research also suggests that once a colon carcinoma develops, if it is going to spread outside the colon, it will do so in less than two years.

What is R0 surgery?

R0 resection indicates a microscopically margin-negative resection, in which no gross or microscopic tumor remains in the primary tumor bed. R1 resection indicates the removal of all macroscopic disease, but microscopic margins are positive for tumor.

Do R1 resections in rectal cancer increase the risk of recurrence?

[email protected]. PMID: 28770270 DOI: 10.1007/s00104-017-0480-6 Abstract R1 resections in rectal cancer particularly affect the circumferential resection margin (CRM) and lead to increased local recurrence rates, more distant metastases and a poorer prognosis.

When is surgical resection indicated in the treatment of rectal cancer?

Surgical resection of locally recurrent rectal cancer should be considered as an initial treatment, especially in patients with less advanced tumors and axial recurrence. In patients with curatively resected rectal cancer, local recurrence is often difficult to treat, may cause severely disabling symptoms, and usually has a fatal outcome.

How is renal cell carcinoma (R0) resection defined?

R0 resection was defined as having no macroscopic or microscopic residual tumor. A total of 20 patients were included in the present study. Tumors were pathologically diagnosed as CRC and classified according to the criteria of the World Health Organization and Union for International Cancer Control, 8th edition [ 17 ].

How long do patients undergoing r0 and R2 resections survive?

Patients undergoing an R0 resection survived on average for 37.6 (95% confidence interval: 23.5-51.7) months longer than those undergoing R1 resection and 53.0 (31.2-74.8) months longer than those undergoing R2 resection. This correlated to a hazard ratio of 2.03 (1.73-2.38) for R0 vs R1 and 3.41 (2.21-5.25) for R0 vs R2.