Johnson et al developed a model for predicting survival in an elderly patient with acute myeloid leukemia (AML). This can help identify a patient who may benefit from more aggressive management. The authors are from the Manchester Royal Infirmary in England.
Patient selection: non-bedridden patient (pretreatment WHO performance scale 0 to 3) >= 60 years of age with untreated AML
Parameters:
(1) pre-treatment performance status (WHO grade = ECOG grade)
(2) absolute blast count in the peripheral blood
(3) hepatomegaly
(4) urea in mmol/L
|
Parameter |
Finding |
Points |
|
performance status |
WHO grade 0 to 2 |
0 |
|
|
WHO grade 3 |
1 |
|
absolute blast count |
< 200 per µL (< 0.2 * 10^9/L) |
0 |
|
|
>= 200 per µL (>= 0.2 * 10^9/L) |
1 |
|
hepatomegaly |
absent |
0 |
|
|
present |
1 |
total score =
= SUM(points for all 3 parameters)
Interpretation:
• minimum score: 0
• maximum score: 3
• Patients were divided into 4 groups based on the number of findings present (0, 1, 2, 3).
• Each group's survival was then plotted vs the serum urea (Figure 2, page 303) over the range of 3-16 mmol/L (8.4 to 44.8 mg/dL BUN)
• The survival can be approximated by curves generated in Minitab.
|
Group |
Urea |
Estimated Median Survival In Weeks |
|
0 |
3-16 |
(0.4444 * ((urea)^2)) - (14.58 * (urea)) + 150.6 |
|
1 |
3-16 |
(0.3986 * ((urea)^2)) - (12.92 * (urea)) + 118.3 |
|
2 |
3-9 |
(0.9762 * ((urea)^2)) - (19.49 * (urea)) + 113.2 |
|
2 |
9-16 |
(0.1131 * ((urea)^2)) - (3.808 * (urea)) + 39.09 |
|
3 |
3-8 |
(0.8536 * ((urea)^2)) - (15.70 * (urea)) + 78.53 |
|
3 |
8-16 |
(0.08431 * ((urea)^2)) - (2.675 * (urea)) + 24.82 |
Limitations:
• The study was published in 1993 and survival has improved since then.
Specialty: Hematology Oncology
