Nomogram of Bevilacqua et al for Predicting Metastases to a Sentinel Lymph Node

NOTE: A separate nomogram that does not include results of receptor studies is shown in Figure 3.

Parameters:

(1) age of the patient in years

(2) diameter of the tumor in cm

(3) special type of tumor with low risk (colloid, medullary, tubular)

(4) location in upper inner quadrant

(5) lymphovascular invasion

(6) multifocal disease

(7) histologic features (nuclear grade for invasive ductal, lobular)

(8) estrogen receptor status

(9) progesterone receptor status

points for age (over range 20 to 100 years) =

= (-0.345 * (age)) + 34.5

points for tumor diameter =

= (0.03943 * ((diameter)^3)) - (0.8341 * ((diameter)^2)) + (13.43 * (diameter)) + 1.759

total score =

= SUM(points for all 9 parameters)

Interpretation:

• minimum score: 0

• maximum score: around 200

• The higher the score the greater the probability of metastases in a sentinel lymph node.

probability of metastases for a score from 0 to 81.4 =

= (0.000095 * ((total score)^3)) - (0.004783 * ((total score)^2)) + (0.1293 * (total score)) - 0.0062

probability of metastases for a score from 81.4 to 101.4 =

=  (0.01535 * ((total score)^2)) - (1.307 * (total score)) + 34.7

probability of metastases for a score from 101.4 to 150 =

= (0.000011 * ((total score)^3)) - (0.01427 * ((total score)^2)) + (3.851 * (total score)) - 195.1

For a score > 150 the probability is > 95%.