Patient selection: esophageal cancer treated with radiation therapy, ECOG performance status 0 to 3
Parameters:
(1) subjective global assessment (SGA) class (A, B or C)
(2) ECOG performance score from 0 to 3
(3) planning target volume to total lung volume ratio (PTV/LV)
(4) mean lung dose (MLD) in Gray
(5) the ratio of change at 4 weeks in the systemic immune inflammation index (SII)
|
Parameter
|
Finding
|
Points
|
|
SGA class
|
A
|
0
|
|
|
B
|
85.8
|
|
|
C
|
100
|
|
ECOG
|
0 or 1
|
0
|
|
|
2 or 3
|
81.68
|
|
PTV to LV ratio
|
< 0.11
|
0
|
|
|
>= 0.11
|
48.39
|
|
mean lung dose
|
< 12 Gy
|
0
|
|
|
>= 12 Gy
|
56.68
|
|
ratio of change in SII at 4 weeks
|
< 1.5
|
0
|
|
|
>= 1.5
|
72.58
|
where:
• The method to calculate the ratio of change in the SII is not clearly states. It may be ((SII at 4 weeks) - (SII at baseline)) / (SII at baseline).
total score =
= SUM(points for all 5 parameters)
Interpretation:
• minimum score: 0
• maximum score: 359.33
• The higher the score the greater the risk of radiation pneumonitis.
X =
= (0.02021 * (score)) - 4.703
probability of radiation pneumonitis =
= 1 / (1 + EXP((-1) * X))
