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Abstract
rephine biopsies of the bone marrow should be carried out,
when clinically indicated, by trained individuals following
a standard operating procedure. A bone marrow aspiration
should be performed as part of the same procedure. For patient
safety and convenience, biopsies are usually performed on the
posterior iliac crest. The biopsy specimen should measure at
least 1.6 cm. If bone marrow aspiration is found to be
impossible, imprints from the biopsy specimen should be
obtained. Otherwise, the specimen is placed immediately into
fixative and after fixation is embedded in a resin or, more
usually, decalcified and embedded in paraffin wax.
Thin sections are cut and are stained, as a minimum, with
haematoxylin and eosin and with a reticulin stain. A Giemsa
stain and Perls’ stain are also desirable. The need for other
histochemical or immunohistochemical stains is determined by
the clinical circumstances and the preliminary findings.
Trephine biopsy sections should be examined and reported in a
systematic manner, assessment being made of the bones, the
vessels and stroma, and the haemopoietic and any lymphoid or
other tissue.
A variety of fixative and decalcification procedures are
routinely used for BM trephines in different parts of the world.
Many, but not all of them, are well suited for
immunohistochemical stains. Fixation in buffered formalin,
decalcification in EDTA, and embedding in paraffin is a good compromise, because it not only provides good morophology
and excellent condition for immmunohistochemistry but also
allows DNA- and RNA-based molecular studies. Acceleration
of decalcification can be achieved by ultrasound up to 6-12 h.
In general, patients who have a hypocellular bone
marrow or bone marrow fibrosis are likely to need a trephine
biopsy for adequate assessment. In such patients, an aspirate
will probably be inadequate or even impossible. Also, trephine
biopsy permits the detection of a bone marrow granulomas, and
focal lymphoid infiltrates. There is also a greater likelihood of
detection of infiltration by non-haemopoietic neoplasms.
Unexplained pancytopenia and an unexplained
leucoerythroblastic blood film are indications for a trephine
biopsy because they are likely to indicate bone marrow
infiltration or fibrosis.
Pathomorphological examination of trephine biopsies of
the bone marrow represents a standard method for the diagnosis
and staging of haematologic neoplasms and other disorders
involving the BM as in patients with malignant lymphoma,
plasma cell dyscrasias, chronic myeproliferative syndrome,
myelodysplastic syndrome, acute leukaemia and metastatic
tumors. BM has main role in B cell lymphoproliferative
disorders diagnosis, staging and classification.
Not all patients with chronic lymphocytic leukaemia
require bone marrow examination because the disease can
usually be diagnosed without difficulty from peripheral bloodcytology and immunophenotyping. Patients with early stage
disease do not require active treatment and bone marrow biopsy
is not essential for management. However, a bone marrow
trephine biopsy is indicated in patients in whom treatment is
necessary, either those with more advanced disease or younger
patients in whom intensive treatment is planned. A trephine
biopsy is essential for follow up of intensive treatment because
it may show residual focal disease when a bone marrow aspirate
is normal. In fact, a bone marrow aspirate is of little value in
chronic lymphocytic leukaemia; it is peripheral blood
examination and trephine biopsy that are important.
A trephine biopsy may permit a diagnosis of non-
Hodgkin’s lymphoma, particularly low grade lymphoma in
which the marrow is often infiltrated. It is also of some use in
classification if a lymph node biopsy is not available because
paratrabecular infiltration is much more common in follicular
lymphoma than in other categories. Biopsy can also be required
for staging purposes .