Zhu et al reported a model for predicting neutropenia after cancer chemotherapy using etoposide. This can help to identify a patient who may require more aggressive management. The authors are from the General Hospital of People's Liberation Army and Chongqing Medical University in China.
Patient selection: etoposide-based chemotherapy for cancer
Model delivery: nomogram
Parameters:
(1) absolute lymphocyte count in 10^9/L
(2) serum total bilirubin in µmol/L
(3) Karnofsky Performance Status (KPS), from 50 to 100
(4) heart disease
(5) number of metastatic sites
(6) surgery <= 4 weeks prior to chemotherapy
(7) alkylating agents
points for Karnofsky Performance Status =
= 200 - (2 * (KPS))
|
Parameter
|
Finding
|
Points
|
|
absolute lymphocyte count
|
>= 0.7 * 10^9/L
|
0
|
|
|
< 0.7 * 10^9/L
|
18
|
|
serum total bilirubin
|
< 25 µmol/L
|
0
|
|
|
>= 25 µmol/L
|
29.5
|
|
heart disease
|
no
|
0
|
|
|
yes
|
18
|
|
number of metastatic sites
|
< 3
|
0
|
|
|
>= 3
|
22.5
|
|
surgery
|
no
|
0
|
|
|
yes
|
26
|
|
alkylating agents
|
no
|
0
|
|
|
yes
|
18
|
total score =
= SUM(points for all of the parameters)
Interpretation:
• minimum score: 0
• maximum score: 232
• The higher the score the greater the risk of neutropenia.
value of X =
= (0.08223 * (score)) - 7.123
probability of neutropenia (including febrile neutropenia) =
= 1 / (1 + EXP((-1) * X))
Performance:
• The area under the ROC curve was 0.93 for the derivation and 0.90 for the validation cohorts.
