A 4-year-old girl is brought by her parents to hospital with a history of pallor, bruising and lethargy. On examination, she has a temperature of 38 °C, heart rate 110 Beat per minute, BP 100/60. She is pale, and has multiple bruises over her arms and legs. She has extensive lymphadenopathy. Cardiovascular and respiratory examinations are within normal limits. She has 4 cm hepatomegaly, and 3 cm splenomegaly.

A full blood count shows:

Hb

6.9 g/dl

WCC

189 × 109/l

Neutrophils

1.3 × 109/l

Lymphocytes

185 × 109/l

Platelets

 28 × 109/l

The blood film shows blasts