Lymphoproliferative Disorders
Introduction
There are two basic categories of lymphoproliferative disorders:
- lymphomas — lymphoid tissue tumours
- leukemias — affect bone marrow, cancer cells are released into the peripheral blood
Lymphomas and leukemias often overlap, because lymphomas may undergo leukemisation and vice versa.
For example small lymphocytic lymphoma/chronic lymphocytic leukemia
or precursor lymphoblastic lymphoma/acute lymphoblastic leukemia:
they are the same disorders with different manifestation.
Lymphomas are detailed in the chapter
Pathology of the lymphatic nodes.
This chapter will focus on lymphoproliferative disorders of the bone marrow.
Histology
Types of tumorous bone marrow infiltration:
- intersticial: the tumour infiltration respects the original
architecture of the marrow and spreads through the intersticium
- nodular: the tumour infiltration forms vague, loosely defined nodules,
which are localized in the peritrabecular or non-peritrabecular spaces
- diffuse, concentrated (packed marrow): a massive
bone marrow affection, with an almost 100% cellularity,
malignant population is predominant, hematopoiesis is only residual
Types of malignant bone marrow infiltration:
- intersticial: the tumour infiltration respects the original
architecture of the marrow and spreads through the intersticium
- nodular: the tumour infiltration forms vague, loosely defined nodules,
which are localized in the peritrabecular or non-peritrabecular spaces
- diffuse, concentrated (packed marrow): a massive
bone marrow affection with an almost 100% cellularity,
malignant population dominates, hematopoiesis is only residual
