2. Learning Objectives
Know the concept of Lymphoma
Know the classification of
lymphomas
Know the most important
morphological changes on
lymphomas
3. What is Lymphoma?
Name for a group of cancers of the
lymphatic system, part of the body's
immune defense system.
It can occur when an error takes place in the
way a lymphocyte is produced. The
resulting abnormal cells accumulate either
by duplicating faster or living longer than
normal cells, and they displace normal
lymphocytes.
4. Like normal lymphocytes, cancerous
lymphocytes can grow in many parts of the
body, including the lymph nodes, spleen,
bone marrow or blood. Because there is
lymph tissue throughout the body, the cancer
cells may spread to other organs
6. Over the years, different classification systems
have been used to differentiate lymphomas
and several groups around the world are
continuing to work on the best way to classify
the various subtypes.
Depending on the classification system being
used, there are between 4 to 6 classes of HD
and anywhere from 15 to over 30 classes of
NHL
7. The simplest way to think of Lymphoma is to
look at whether :
It arises from a B- or T-cell lymphocyte (90%
of lymphomas are of B-cell origin)
it is a slow progressing lymphoma (indolent)
or a fast progressing lymphoma (aggressive)
All Hodgkin’s disease lymphomas are B-Cell
lymphomas, so they can be further classified
by “classic” or "lymphocyte predominant”
HD.
8. All Hodgkin's Disease lymphomas
are B-Cell malignancies
There are over 30 different NHL
subtypes, classified by a
combination of the two categories
described
9. Lymphoma accounts for about 3 percent of
all cases of cancer in the United States.
Unfortunately, while the incidence rate of
many other cancers is decreasing, the
incidence rate for lymphoma is rising.
Each year, 60,900 persons in the United
States learn they have lymphoma. This
figure includes approximately 7,000 new
cases of Hodgkin’s disease (HD) and 53,900
new cases of Non-Hodgkin’s Lymphoma
Incidence of Lymphoma
10. Facts about Lymphoma
Non-Hodgkin’s Lymphoma is a
much larger percentage of all
lymphoma cases than Hodgkin’s
Disease
The pattern by age group varies
for Hodgkin’s Disease vs. Non-
Hodgkin’s Lymphoma
11.
12. The incidence of Non-Hodgkin’s
Lymphoma increases dramatically
with age.
Hodgkin’s Disease peaks among
young adults
(people in their mid-20s)
falls to less than half that rate in
middle age and increases
infrequency in older adults
25. Within his category fall:
African (endemic) Burkitt Lymphoma
Sporadic (nonendemic) Burkitt Lymphoma
A subset of aggressive lymphomas occurring
in individuals infected with HIV.
26.
27. Burkitt Lymphomas occurring in
each of these settings are
histologically identical, but some
clinical, genotypic, and virologic
differences exist.
28. Morphology
Involved tissue are effaced by a diffuse
infiltrate of intermediate-sized
lymphoid cells, 10-25 µ in diameter,
containing round or oval nuclei, and
with coarse chromatin, several
nucleoli and moderate amount of
faintly basophilic or amphophilic
cytoplasm.
29. The nuclear size approximates that of
benign macrophages within the
tumor.
A high mitotic index is typical, as in
apoptotic tumor cell death,
accounting for the presence of
numerous tissue macrophages with
ingested nuclear debris.
Morphology
30. These benign macrophages are
diffusely ly distributed among the
tumor cells and have abundant clear
cell cytoplasm, creating a
characteristic “starry sky” pattern.
Morphology
31. In case with bone marrow involvement,
the tumor cells in marrow aspirates have
slightly clumped nuclear chromatin, two
to five distinct nucleoli, and royal blue
cytoplasm containing multiple, clear
cytoplasmic vacuoles.
Morphology
32. Immunophenotype
These are tumors of mature B cells
expressing surface IgM,
monotypic Ƙ or ƛ light chain,
CD19. CD20, and CD10, and BCl6,
a phenotype that closely
resembles that of rapidly dividing
B cells within the dark zones of
normal germinal centers.
33. Cytogenetic and molecular
Genetic Features
All forms of Burkitt lymphomas are
associated with translocations of the
c-MYC gene on chromosome 8.
The pattern in the translocation is
usually the IgH occurs (t(8;14)) but
may be also be the Ƙ )(t:2;8)) or ƛ
((t(8;22)) light chain locus.
34. Essentially all endemic tumors are
latently infected with EBV, which is
also present in about 25% of HIV-
associated tumors and 15% to 20%
of sporadic cases.
Cytogenetic and molecular
Genetic Features:
35. Molecular analysis has shown that
the configuration of the episomal
EBV DNA, is identically in all
tumors cells within the individual
cases, indicating that infection
precedes cellular transformation.
Cytogenetic and molecular
Genetic Features:
36. Clinical Features
Both endemic and sporadic cases
are found largely in children and
young adults, accounting for
approximately 30 % of childhood
NHLs in the United State
37. Most tumors manifest at extranodal
sites.
Endemic Burkitt Lymphoma most often
presents as an abdominal mass
involving the ileocecum and
peritoneum. Involvement of the bone
marrow and peripheral blood is
uncommon, specially in endemic cases.
Burkitt Lymphoma is very aggressive but
responds well to short-term high doses
chemotherapy
Clinical Features
38. Most tumors manifest at
extranodal sites.
Endemic Burkitt Lymphoma most
often presents as an abdominal
mass involving the ileocecum and
peritoneum.
Clinical Features
39. Involvement of the bone marrow and
peripheral blood is uncommon,
specially in endemic cases.
Burkitt Lymphoma is very aggressive
but responds well to short-term high
doses chemotherapy
Clinical Features
40. Patient and material collection In Uganda
Population
95 cases from Ugandan tribes
2-64 years (median age: 16)
Site of involvement:
- lymph node (34 cases)
- abdomen (26 cases)
- gonads (25 cases)
- jaw (10 cases)
(Formalin fixed paraffin embedded blocks punched and collected in 2 TMA
blocks (48 and 47 cases each)
International Conference 2008, Kampala
46. Next topics
• Non Neoplastic Disease of Bone
• Tumor of Bone
• Inflammatory disease of joint
• Synovial Sarcoma
• Tumour of skeletal muscle
• Tumours of smooth muscle
