Internal Medicine

0521779407-01 CUNY1086/Karliner 0 521 77940 7 June 4, 2007 20:45

32 Acute Lymphoblastic Leukemia

■Flow Cytometric Analysis of ALL: Precursor B cell (CD19, CD22,

CD79a, CD10+/−): These cells are Tdt positive, in contrast to mature

B-ALL.

■Mature B cell (correlates with former L3 classification): CD19+;

CD20+; CD22+; CD79a+;sIg+; Others: Tdt-; CD34-; CD10+/−

■Precursor T cell: CD7+; cCD3+; CD5+; CD4+/−; CD8+/−; CD34+;

TdT+

■Critically important decisions will be based upon subtype charac-

terization, but essential to confirm that this is ALL.

Other Critical Initial Testing

■Send blood for basic assessment of hematologic and metabolic sta-

tus including CBC with differential, coagulation profile; chemistries

including electrolytes; renal and liver function, uric acid, calcium,

phosphate, and magnesium; HLA typing for potential stem cell trans-

plantation including patient, siblings, and parent

■Chest x-ray PA & lateral to evaluate for infection and/or a mediastinal

mass

Other Laboratory Tests

■Molecular and immunophenotypic characterization of leukemic

cells specifically to monitor disease (e.g., search for minimal resid-

ual disease following therapy and potentially useful in follow-up for

early relapse)

■Immunophenotypic analysis searching for monoclonal population

of leukemic cells as well as RT-PCR important for quantitating min-

imal residual disease at time of remission (and may be helpful with

relapse surveillance)

■Imaging studies to assess bulk disease (e.g., CT scan of chest &

abdomen)

■Lumbar puncture to assess for CNS disease: Prophylactic treatment

essentially required in every case. If the patient has symptoms at

presentation, CSF exam is essential. Therapy should also be admin-

istered intrathecally along with diagnostic studies. However, in the

asymptomatic patient, CNS examination may be accomplished after

the patient is stabilized on systemic therapy because of requirement

for serial treatment of the CNS compartment. Recent data show that

traumatic lumbar puncture may have an adverse impact on survival,

necessitating an experienced person to do the initial lumbar punc-

tures, and rationalizes the introduction of prophylactic chemother-

apy with initial diagnostic tap.