Final Staging

Rectum cancers should be staged using the TNM staging system:

• cTNM: pre-treatment clinical classification, based on clinical examination, imaging, endoscopy, biopsy, surgical exploration or other;
• yTNM: classification after induction therapy;
• pTNM: post-surgical histopathological classification.

T - Primary Tumour

		

			

				

					
Tx
Primary tumour cannot be assessed
				
				

					
T0
No evidence of primary tumour
				
				

					
Tis
Carcinoma in situ: intraepithelial or invasion of lamina propria
				
				

					
T1
Tumour invades submucosa
				
				

					
T2
Tumour invades muscularis propria
				
				

					
T3
Tumour invades through the muscularis propria into the
subserosa, or into nonperitonealized pericolic or perirectal
tissues
				
				

					
T4
Tumour directly invades other organs or structures and/or
perforates visceral peritoneum
				
			
		
		

N - Regional Lymph Nodes

		

			

				

					
Nx
Regional lymph nodes cannot be assessed
				
				

					
N0
No metastases in regional lymph nodes
				
				

					
N1
Metastases in 1 to 3 regional lymph nodes
				
				

					
N2
Metastasis in 4 or more regional lymph nodes
				
			
		
		

A tumour nodule in the pericolorectal adipose tissue of a primary carcinoma without histologic evidence of residual lymph node in the nodule is classified in the pn category as a regional lymph node metastasis if the nodule has the form and smooth contour of a lymph node. If the nodule has an irregular contour, it should be classified in the T category and also coded as V1 (microscopic venous invasion) or as V2 (if it was grossly evident), because there is a strong likelihood that it represents venous invasion.

M - Distant metastases

			

			

				

					
Mx
Presence or absence of distant metastases cannot be
determined
				
				

					
M0
No distant metastases detected
				
				

					
M1
Distant metastases detected
				
			
		
		

TNM Stage grouping

		

			

				

					
Stage 0
Tis
N0
M0
				
				

					
Stage I
T1 or T2
N0
M0
				
				

					
Stage II A
T3
N0
M0
				
				

					
Stage II B
T4
N0
M0
				
				

					
Stage III A
T1 or T2
N1
M0
				
				

					
Stage III B
T3 or T4
N1
M0
				
				

					
Stage III C
Any T
N2
M0
				
				

					
Stage IV
Any T
Any N
M1
				
			
		
		

G - Histologic grade

		

			

				

					
Gx
Grade cannot be assessed
				
				

					
G1
Well differentiated
				
				

					
G2
Moderately differentiated
				
				

					
G3
Poorly differentiated
				
				

					
G4
Undifferentiated
				
			
		
		

The staging is done during the second multidisciplinary meeting (MOC) on the basis of all results and reports.

If possible, the general practitioner of the patient should attend this meeting. If not, the staging has to be fully and clearly communicated to the GP and/or specialist of the patient.

Depending on the tumour stage, the further treatment options are decided:

		

			

				

					
Stage I
Patient oriented to follow up procedure
				
				

					
Stage II
Chemotherapy is discussed on the basis of risk assessment
				
				

					
Stage IIII
Patient must receive chemotherapy (if no major objection)
				
				

					
Stage IV
See metastatic disease
				
			
		
		

Adjuvant radiotherapy combined with chemotherapy could be an option, although there is no clear evidence that this combination improves survival.

The chemotherapy adjuvant regimen is decided during the multidisciplinary team meeting.

A written report with staging and treatment options is mandatory for each patient.