Page 497 - Clinical Hematology_ Theory _ Procedures ( PDFDrive )

CHAPTER 24 ■ Myelodysplastic Syndromes and Myelodysplastic/Myeloproliferative Neoplasms 481

by ut tions o genes th t re ut te recurrently occur. A T e e i n surviv l ti e or ll p tients with MDS is
subset o ut te genes re likely to initi te lesions th t pro- bout 2 ye rs. In the types o MDS with 5% to 30% or ore

ote exp nsion o s ll lign nt clone. bone rrow bl sts, the risk o progression to AML is high,

especi lly in chil hoo , n usu lly le s to e th.

RELATIONSHIP OF CYTOGENETICS TO T e e i n surviv l is 20 to 40 onths. Progression to

PROGNOSIS AML occurs in bout 15% to 30% o p tients. T e percent-
ge o peripher l bloo n bone rrow bl sts is the ost

MDS p tients with ultiple cytogenetic no lies h ve i port nt ctor in eter ining surviv l. Co plic tions o

shorter surviv l ti e ( ver ge, 8 onths) th n o p tients with bone rrow ilure, inclu ing in ections n he orrh ge,

single no lies ( ver ge, 18 onths) or those with nor l re jor c uses o e th.

k ryotype ( ver ge, 36 onths). r ns or tion to AML c n

be observe in pproxi tely 25% o p tients with nor l

k ryotype, n ver ge o 40% o p tients with single no - TREATMENT STRATEGIES

lies, n 50% o p tients with ultiple ch nges. T ere ore, n Gener l tre t ent or MDS n MPN is RBC or pl telet

unst ble k ryotype c n be ssoci te with poor prognosis. tr ns usion to control ne i or blee ing. Vit ins or other

P tients with MDS n p tients with AML sh re cert in rugs y lso be given s supple ent. Che other py n

specif c k ryotypes. P tients with un vor ble k ryotypes biologic l ther py re being teste in clinic l tri ls. Biologic l

h ve si il rly short surviv l ti es. P tients with iploi ther py is so eti es c lle biologic l response o if er

k ryotypes survive signif c ntly longer but with rel tively ther py or i unother py. Bone rrow tr nspl nt tion is

inor i erences between p tients with v rious i gnoses. newer tre t ent ppro ch.

Cl ssif c tion o p tients with excess yelobl sts in the r- T e choice o tre t ent epen s on the type o MDS s

row ight ore ppropri tely be b se on cytogenetics th n well s the p tient’s ge n over ll he lth. St n r proto-

on the istinction between MDS n AML. col tre t ent y be consi ere bec use o its e ectiveness

T e bsence o cytogenetic lly nor l cells in ic tes in p tients in the p st, but ost p tients with MDS re not

poor prognosis with requent progression to AML, which is cure with st n r ther py. P rticip tion in clinic l tri l

resist nt to che other py. Progression to AML epen s not o n experi ent l rug y be better option.

only on chro oso l bnor lities but lso on FAB sub- I p tient h s MDS with no previous history o ise se

type. P tients with onoso y 7, el(7q), triso y 8, or i(17q) ( e novo present tion), tre t ent y t ke the or o one

h ve shorter surviv l ti es, ore requent progression to o the ollowing:

leuke i , n less response to tre t ent with 13-cis retinoic

ci th n o p tients with el(20q) or t(2;11). 1. Supportive c re to relieve sy pto s o the ise se, such

One o the ost wi ely use prognostic syste s or MDS s ne i or blee ing

p tients is the Intern tion l Prognostic Scoring Syste 2. I unother py (e.g., gr nulocyte colony-sti ul ting

(IPSS) ( ble 24.4). P tients with ewer bone rrow bl sts ctor [G-CSF], gr nulocyte- croph ge colony–sti u-

n with better cytogenetics (nor l, 5q, 20q, Y) h ve l ting ctors [GM-CSF], n erythropoietin)

prolonge e i n surviv l, n those with ore bl sts n 3. Che other py (e.g., i rubicin, itox ntrone, cytosine,

worse cytogenetics (co plex or bnor lities o chro o- n unorubicin)

so e 7) h ve shorter surviv l. 4. Allogeneic bone rrow/ste cell tr nspl nt tion

TABLE 24.4 International Prognostic Scoring System

Prognostic Variables 0 1 2 3 4

Very Good Good Intermediate Poor Very Poor

% Blasts in bone ≤2% >2%–5% 5%–10% >10% –

marrow

Hemoglobin (g/dL) ≥10 8–<10 <8 – –

Platelet count (×10 /L) ≥100 <50 – – –
9

Cytogenetics −Y del(11q) Normal, −Y del(5q), del (7q), +8, +9, −7, inv(3)/t(3q)/del(3q), Complex: >3
,
,
del(12p), del(20q), +19, i(17q), any other double including −7/ abnormalities

double including del(5q) single or double del(7q), complex:

abnormalities or chro- independent clones 3 abnormalities

mosome 7 anomalies