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Chapter 12: Leukaemia and lymphoma 487

recurrent infections and/or easy bruising and mucosal
bleeding. Other presentations include lymph node en-
largement, bone and joint pain. On examination there
Proerythroblast Myeloid Stem cell Megakaryoblast may be pallor, bruising, hepatosplenomegaly and lym-
phadenopathy.
Myeloblast
Erythrocyte Platelet
Microscopy
Monoblast Promyelocyte Abnormal leukaemic cells of the myeloid cell line replace
the normal marrow. Morphologically the blast cells in
AML may contain a stick like inclusion – Auer rods.
Monocyte Myelocyte
The leukaemia is typed by cytochemical staining and
Granulocyte monoclonal antibodies to look for cell surface markers.

Figure 12.11 Myeloid haemopoesis. Investigations
Blasts are seen in a peripheral blood film. Full blood
count shows a low haemoglobin, variable white count,
M2 Myelocytic leukaemia with differentiation
low platelet count. Bone marrow aspiration shows in-
M3 Acute promyelocytic leukaemia
creased cellularity with a high percentage of the abnor-
M4 Acute myelomonocytic leukaemia
mal cells. Bone marrow cytogentic studies allow classi-
M5 Acute monocytic leukaemia proliferation of mono-
fication into prognostic groups (e.g. t(8:21) and inv 16
blasts
are good prognostic indicators, whereas −7 and −5 and
M6 Acute erythroblastic leukaemia (myeloblasts &
poor prognostic indicators).
proerythroblasts)
M7 Acute megakaryocytic leukaemia – myeloblasts &
Management
megakaryoblasts (uncommon)
High dose cytotoxic drugs doxorubicine, cytosine,
PatientswithM3(acutepromyelocyticleukaemia)are

etoposide are given cyclically. Supportive treatments in-
particularly prone to disseminated intravascular co-
clude red blood cell transfusions, platelet transfusions
agulation due to the presence of procoagulants within
and broad-spectrum antibiotics. Bone marrow trans-
the cytoplasmic granules of the promyelocyte. In M3
plantation may be used.
there is a characteristic chromosomal translocation
t(15:17), the promyelocytic leukaemia (PML) gene
and the retinoic acid receptor come to lie next to Prognosis
each other and are therefore deregulated. Ninety-five 70% of those under 60 years will achieve remission with
percent of patients with M3 are induced into remis- combination chemotherapy although the majority re-
sion by treatment with high dose retinoic acid. This lapse within 3 years.
is not sustained and chemotherapy should also be
used.
Cells in M5 (acute monocytic leukaemia) secrete
Chronic leukaemia
lysozyme (an antibacterial enzyme) which can dam-
age the renal tubules causing hypokalaemia. Gum Chronic lymphocytic leukaemia
hypertrophy and hepatosplenomegaly is common
Definition
within this subgroup.
Chronic lymphocytic leukaemia (CLL) is a leukaemic
proliferation of mature B lymphocytes.
Clinical features
Often there is an insidious onset of anorexia, malaise Incidence
and lethargy due to anaemia. There is often a history of 1.8–3 per 100,000 per year