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Overview :
Den Boer et al stratified children with acute lymphoblastic
leukemia (ALL) based on the in vitro resistance to prednisolone, vincristine
and asparaginase. This can identify patients who may benefit from more aggressive
management. The authors are from the Dutch Childhood Leukemia Study Group and
the German Cooperative Study Group for Childhood Acute Lymphoblastic Leukema
(COALL).
In vitro testing:
(1) prednisolone (P)
(2) vincristine (V)
(3) asparaginase (A)
|
Chemotherapeutic
Agent
|
In Vitro Response
|
Points
|
|
prednisolone
|
sensitive
|
1
|
|
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intermediate sensitivity
|
2
|
|
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resistant
|
3
|
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vincristine
|
sensitive
|
1
|
|
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intermediate sensitivity
|
2
|
|
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resistant
|
3
|
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asparaginase
|
sensitive
|
1
|
|
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intermediate sensitivity
|
2
|
|
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resistant
|
3
|
PVA (prednisolone-vincristine-asparaginase) score =
= SUM(points for all 3 drugs)
Interpretation:
• minimum score: 3
• maximum score: 9
• A highly sensitive leukemia has a score of 3.
• A highly resistant leukemia has a score of 9.
The high risk group had higher rate of:
(1) nonresponse (no remission at 56 days after starting
chemotherapy)
(2) relapse within 2.5 years of diagnosis
|
PVA Score
|
Risk Group
|
Rate of Nonresponse or Early Relapse
|
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3 or 4
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low
|
10%
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5 or 6
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intermediate
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15%
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7, 8 or 9
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high
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24%
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see Table 3, page
3265
The profile was not predictive of late relapse (relapse >
2.5 years after diagnosis).
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