Pathological Models of Zaino et al for Predicting Outcome in Stage I and II Endometrial Adenocarcinoma

Independent prognostic variables confirmed as important for prognosis:

(1) age of the patient

(2) depth of myometrial invasion

(3) histologic grade and cell type

 

Clinical Model (staging by FIGO 1971)

 

Parameter	Finding	Relative Risk
pathology	endometrioid, grade 1	1.0
	endometrioid, grade 2	1.6
	endometrioid, grade 3	2.6
	clear cell, grade 1	7.1
	clear cell, grade 2	3.8
	clear cell, grade 3	2.0
	serous, grade 1	2.9
	serous, grade 2	4.4
	serous, grade 3	6.6
	endometrioid with squamous differentiation, grade 1	0.8
	endometrioid with squamous differentiation, grade 2	1.0
	endometrioid with squamous differentiation, grade 3	1.2
	villoglandular, grade 1	0.4
	villoglandular, grade 2	1.3
	villoglandular, grade 3	4.5
myometrial invasion	endometrium only (in situ)	1.0
	superficial	1.2
	middle	1.6
	deep	3.0
pelvic washings	positive	3.0
	negative	1.0
age	45 (arbitrary reference)	1.0
	55	2.0
	65	3.4
	75	4.7
vascular space involvement	present	1.5
	absent	1.0

 

where:

• The assigned relative risks for clear cell tumors (with grade 1 greater than grade 2 or 3)  appear counter-intuitive to me.

 

If the age vs risk is plotted in JMP, the following equation is given (for women > 45 years of age):

 

relative risk for age =

= (0.00075 * ((age in years)^2)) + (0.035 * (age in years)) - 2.11875

 

cumulative relative risk =

= (relative risk for pathologic type) * (relative risk for myometrial invasion) * (relative risk for pelvic washing) * (relative risk for age) * (relative risk for vascular space involvement)

 

The survival for the woman is then read from Figure 1 (page 1119).

 

If the 5 year (60 month) survival from Figure 1 is plotted vs relative risk in JMP, the following equation is given:

 

survival as a decimal fraction =

= (-0.0342 * (relative risk)) + 1.0255

 

Surgical Model

 

Parameter	Finding	Relative Risk
pathology	endometrioid, grade 1	1.0
	endometrioid, grade 2	1.3
	endometrioid, grade 3	1.8
	clear cell, grade 1	5.1
	clear cell, grade 2	3.5
	clear cell, grade 3	2.5
	serous, grade 1	2.2
	serous, grade 2	3.1
	serous, grade 3	4.4
	endometrioid with squamous differentiation, grade 1	1.2
	endometrioid with squamous differentiation, grade 2	1.0
	endometrioid with squamous differentiation, grade 3	0.8
	villoglandular, grade 1	0.01
	villoglandular, grade 2	0.5
	villoglandular, grade 3	41.9
myometrial invasion	endometrium only (in situ)	1.0
	superficial	0.5
	middle	3.3
	deep	4.6
age	45 (arbitrary reference)	1.0
	55	2.3
	65	4.6
	75	7.6
vascular space involvement	present	1.4
	absent	1.0

 

where:

• Some of the assigned relative risks appear counter-intuitive to me. For example: (1) the risk for an in-situ tumor is higher than for superficial invasion; (2) a grade 3 endometrioid with squamous differentiation is less than grade 1; (3) a grade 1 clear cell tumor is greater than a grade 2 or 3 tumor.

 

If the age vs risk is plotted in JMP, the following equation is given (for women > 45 years of age):

 

relative risk for age =

= (0.00425 * ((age in years)^2)) - (0.289 * (age in years)) + 5.38375

 

cumulative relative risk =

= (relative risk for pathologic type) * (relative risk for myometrial invasion) * (relative risk for age) * (relative risk for vascular space involvement)

 

The survival for the woman is then read from Figure 2 (page 1120).

 

If the 5 year (60 month) survival from Figure 2 is plotted vs relative risk in JMP, the following equation is given:

 

survival as a decimal fraction =

= (-0.006 * (relative risk)) + 0.98