Page 496 - Clinical Hematology_ Theory _ Procedures ( PDFDrive )

480 PART 6 ■ Neoplastic Disorders

v lue (gre ter th n 1%) in cytopenic p tient woul suggest

i gnosis o MDS.

Additional Hem atological Features

Nu erous orphologic l e tures h ve been observe in the

bone rrow n peripher l bloo o p tients with MDS.

In ition, subtle orphologic l e ture, internuclear

bridging (INB), w s recently recognize in MDS. T e occur-

rence o INB in MDS suggests n un erlying bnor lity o

itotic ivision th t coul expl in the i p ire pro uction

o he topoietic cells, the cytogenetic ch nges o ition

n eletion, n the stepwise ise se progression n cyto-

genetic progression ch r cteristic o MDS. L ck o w reness FIGURE 24.2 Re r ctory ne i with ring si erobl sts (Prussi n

th t INB occurs in MDS y c use con usion o MDS with blue st in ×1,250). (Reprinte ro Greer JP, Foerster J, Ro gers

congenit l yserythropoietic ne i type I, congenit l GM, et l. Wintrobe’s Clinical Hematology, Phil elphi , PA:

process lso ch r cterize by INB. Lippincott Willi s & Wilkins, 2004, with per ission.)

Intr cellul r lk line phosph t se ctivities in peripher l

neutrophils re ecre se in MDS co p re with he lthy

controls. T e e sure ent o intr cellul r lk line phos- the nucle te erythroi cells o the bone rrow, re or e

ph t se ctivity is use ul or supporting i gnosis o MDS. when iron eposits encircle the nuclei o erythroi precur-

Ly phoi gglutin tion or cell clusters o bl st cells re sors. Over ti e, the nu ber o yspl stic si erobl sts n the

lso seen in biopsy speci ens ro p tients with MDS. e ull ry iron levels incre se in p r llel, n seru erritin

levels ste ily rise. A s ll nu ber o p tients eventu lly

Features of Selected Types of evelop he ochro tosis. In these p tients, the inci ence

Myelodysplastic Syndromes o HLA-A3 is signif c ntly higher (71%) th n in the gener l
popul tion, which suggests th t p tients in this subgroup

Refractory anemia (RA), one o the re r ctory cytopeni s with inherite gene or he ochro tosis n l ter cquire

uniline ge yspl si , is the il est or o ll types o MDS. ut nt one or RARS.

Approxi tely 20% o p tients h ve this type o MDS. Most Te percent ge o reticulocytes n the tot l peripher l

p tients exhibit p ncytopeni . T e percent ge o reticulo- RBC count re typic lly ecre se , lthough ew p tients

cytes n the tot l peripher l re bloo count re typic lly ni est leukocytopeni or thro bocytopeni . Erythroi

ecre se . Peripher l erythrocytes h ve ten ency to be i orphis is present, with crocytosis pre o in ting.

crocytic. Decre se he oglobin levels re c use by n It is i port nt to note th t RARS is not rel te etio-

i p ire rele se o erythrocytes ro the bone rrow. logic lly to congenit l or s o si erobl stic ne i or to

T e tot l peripher l bloo leukocyte n pl telet counts re cquire , secon ry si erobl stic ne i s.

either nor l or ecre se . So e neutrophils re gr nul r Refractory anemia with excess blasts (RAEB-1 and RAEB-2) is

or tetr ploi . Gi nt pl telets re co on. T e level o bone the f rst MDS type to e onstr te n overt cl ssic rel tionship

rrow stor ge iron is incre se . to AML, th t is, n elev te percent ge o type I n type II

Refractory anemia with ring sideroblasts (RARSs) is si il r yelobl sts in the bone rrow n the presence o yelo-

to RA but i ers bec use o the presence o ring si erobl sts bl sts in the circul ting bloo . RAEB is the ost requent o

(Figs. 24.1 n 24.2). Ring si erobl sts, which excee 15% o the MDS types, representing 40% to 50% o ll new c ses.

Dyserythropoiesis, ysgr nulocytopoiesis, n ys eg -

k ryocytopoiesis re co on. Ane i is usu lly crocytic

n o en i orphic, n ov l crocytes y be present.

A v ri ble nu ber o ring si erobl sts re lso present.

Gr nulocytic bnor lities c n inclu e pseu o–Pelger-Huët

no ly, ring-sh pe nuclei, n gr nul r or hypergr nu-

l r or s. About h l o RAEB p tients exhibit gi nt pl telets

n icro eg k ryocytes.

Te percent ge o reticulocytes n the tot l periph-

er l RBC count, white bloo cell (WBC) count, n pl telet

count re typic lly ecre se . T e presence o cytopeni s n
FIGURE 24.1 Ring si erobl sts. T e l rge gr nules with st in ble
iron, ter e iseroso es, ppe r in the bnor l erythrobl sts sur- yspoiesis istinguishes RAEB ro chronic yelogenous

roun ing the nucleus o the cells like ring. (Prussi n blue st in.) leuke i .

(Reprinte ro H n in RI, Lux SE, Stossel P. Blood: Principles Idiopathic cytopenia of undetermined signi cance (ICUS).
and Practice o Hematology, 2n e , Phil elphi , PA: Lippincott T is c tegory escries p tients in who MDS is possible

Willi s & Wilkins, 2003, with per ission.) but not proven. Age-rel te he topoietic clones riven