Log Odds of Positive Lymph Nodes (LODDS) in a Patient with Colon Cancer

 

Parameters:

(1) total number of lymph nodes retrieved

(2) number of lymph nodes positive

 

A = (positive lymph nodes) + 0.5

B = (total number of nodes) - (positive nodes) + 0.5 = (negative nodes) + 0.5

 

log odds =

= EXP(A/B)

log odds	Group
< - 2.2	LODDS1
-2.2 to -1.11	LODDS2
-1.10 to -0.01	LODDS3
0 to 1.09	LODDS4
>= 1.10	LODDS5

 

where:

• A log odds -2.2 corresponds to 1 positive lymph node out of a total 14 (7%).

• A log odds -1.11 corresponds to 1 positive lymph node out of a total of 5 (20%).

• A log odds of 0 corresponds to 1 positive lymph node out of a total of 2 (50%).

• A log odds of 1.1 corresponds to 1 positive lymph nodes out of 1 (near 100%).

• If 0 lymph nodes in 20 are positive, then the LODDS is -3.7 corresponding to LODDS1.

• LOGS10 was excluded as the operator because the LODDS 5 would correspond to 1 positive node out of 0.62.