Pathology of Lymph Nodes Norman Levy, MD Big Picture As with other organs, lymph nodes, and more globally, the immune system, can.
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Transcript Pathology of Lymph Nodes Norman Levy, MD Big Picture As with other organs, lymph nodes, and more globally, the immune system, can.
Pathology of Lymph Nodes
Norman Levy, MD
Big Picture
As with other organs, lymph nodes, and more globally, the
immune system, can be the site of infectious, immune and
neoplastic disease, the latter either primary or metastatic
The clinical manifestations of diseases of the lymph nodes
are:
Local enlargement, tender on nontender, +/_
Compression of adjacent structures +/_
Release of cytokines producing "systemic" symptoms
of fever, weight loss and night sweats
Infectious organisms can stimulate the same acute, chronic
or granulomatous reactions in the draining lymph nodes as
they characteristically stimulate at other sites
Big Picture 2
Several types of immune stimuli can cause "reactive"
enlargement of the entire lymph node, or selective
expansion of cortical, paracortical or medullary regions
Metastatic tumors spread to the lymph nodes primarily via
lymphatic drainage from adjacent solid organs
Primary neoplasms of the lymph nodes are all malignant
They are divided into malignant non-Hodgkin's
lymphomas (NHL), and Hodgkin lymphoma
Big Picture 3
NHL's are more common, and can be simply divided into
indolent, or slow growing types, and aggressive types
Malignant lymphomas represent clonal malignancies in
which mutational events have caused the majority of
progeny cells to freeze at a single stage of normal
lymphocyte differentiation
Lymphomas frozen at a stage associated with high
replication --> aggressive lymphomas;
Lymphomas frozen at stages associated with
recirculation or final function --> indolent lymphomas
Big Picture 4
The diagnosis of malignant lymphomas is based on the
microscopic recognition of the dominant cytologic cell
type, supplemented by immunologic and molecular
techniques
The treatment and prognosis of lymphomas are based on
The dominant cell type (and it's inherent biologic
behavior),
The extent of spread (Stage)
The underlying health of the patient
All of the previous statements are complicated by the fact
that indolent lymphomas can further mutate and transform
to aggressive types
Big Picture 5
Hodgkin lymphoma is a less common nodal disease
whose diagnosis is based on the detection of a
characteristic cell, the Reed Sternberg cell, in the
appropriate histologic setting
There are several (five) histologic subtypes, but prognosis
is based primarily on extent of disease
Hodgkin lymphoma is a more curable disease than nonHodgkin lymphomas
Now watch me confuse this relatively straightforward
information with the details.
Overview of the lymphoid
immune system
Lymphocytes evolve from pluripotent stem cells --> two
major functional cell types:
B lymphocytes, comprising the humoral immune -->
production of antibodies
T lymphocytes, comprising the cellular immune
system, -->
• Direct killing of foreign or intracellularly infected
cells, cytotoxic T cells
• Fine control of the immune response through the
secretion of cytokines, helper and suppressor T
cells.
Anatomical organization
The anatomic organization of the lymphoid immune system
divided into two major functional regions:
The primary immune organs, sites of initial maturation -->
immune competent cells:
• B cells- bone marrow
• T cells- thymus
The secondary immune organs, sites of antigen driven
replication and differentiation into committed effector cells
• Lymph nodes
• Spleen
• Mucosal Associated Lymphoid System (MALT)- lymphoid
cells lining the respiratory and gastrointestinal tracts
• Everywhere else
The lymph nodes, in their totality, represent the largest secondary
organ, and the major site of lymphoid pathology
Lymph node anatomy
To recognize
lymph node
pathology,
one has to
be familiar
with normal
lymph node
anatomy
and cytology
Lymph node histology
Lymph node variation
Lymph node histology
is dynamic: follicles
In the absence of
immune stimulation,
primary follicles
In the presence of
immune stimulation,
secondary follicles or
germinal centers
Lymphocyte homing
After initial maturation in the primary
immune organs, "virgin" B and T
lymphocytes --> peripheral blood -->
home to specific sites within the lymph
node (and the other secondary
organs),
The sites of B cell homing include:
The primary and secondary
follicles of cortex-the sites of
• antigen presentation
• proliferation and
differentiation in response to
same
The medullary cords -->plasma
cells aggregate--> release their
immunoglobulins into the efferent
lymph
The site of T cell homing is the
paracortex
The separation of B and T lymphocytes
not absolute,
Both cell types present throughout
lymph node, necessary for coordinated
lymphoid immune response.
Lymphocyte recirculation
Normal lymphocytes recirculate, passing from blood -->
lymph nodes --> efferent lymphatics
Allows constant surveillance for the presence of the
antigen for which the lymphocyte has a unique and
specific receptor on it's surface.
If antigen not present, lymphocytes leave the node and
recirculate
Virgin lymphocytes have a finite lifespan, numbered in
weeks, unless they come in contact with antigen
Cytology of the lymph node
The normal or reactive lymph node is thus a dynamic organ
Composed of
Transient B and T lymphocytes
Antigen processing and presenting cells
Replicating B and T lymphocytes (in response to antigen)
Persistent and transient final effector cells
Macrophages
Some of these functional subgroups are cytologically unique,
others cytologically indistinguishable
The ultimate microscopic impression, with practice, is one of
cytologic heterogeneity, and histologic organization
Cell types I
Small lymphocytes
Small round dark blue dots. Round
nucleus, clumped chromatin, small or
absent nucleolus.
The dullest looking cells hiding the
greatest level of functional
heterogeneity.
• Can be T or B cell, virgin
(unexposed to antigen) or
differentiated effector/memory cell.
• Most likely lineage, B or T,
guessed by location within the
node, but lineage and state of
differentiation must be confirmed
by immunologic/molecular
techniques
Locations:
• B cells- primary follicles,
mantle zone of secondary
follicles, medullary cords
• T cells- paracortex, minor
population within germinal
center.
Kinetically, clumped
chromatin tells us that the cell is
not proliferating- not activated
to enter the cell cycle and
replicate
Cell types 2:Follicular (germinal)
center cells
Replicating and post-replicating B cells
Noncleaved cells, small and large
• Replicating populationsexpanding antigen responsive
cells.
• Round nuclei but larger than
resting small lymphocyte
• Open or vesicular chromatin
• Recognizable nucleoli.
– Nucleus clear -->genetic
material unwound for
replication.
• Size, large or small compared
nucleus of macrophage.
Small cleaved cells• Nonreplicating population
• Post mitotic memory or plasma
cell precursors
• Clumped chromatin
• Irregular folded and cleaved
nuclear profiles
Reactive germinal center
MZ
LZ
DZ
Cytology of lymph node 3
Immunoblasts
Accessory cells
Replicating large cells found
Antigen processing cells
outside the germinal centers.
• Interdigitating reticulin cells- T cell
May be of B or T cell type
paracortex
Have nuclear characteristics of
• Dendritic reticulin cells- B cell germinal
replicating lymphocytescenters
• Vesicular chromatin
• Process and present antigen to B and T
lymphocytes
• Nucleoli
• Invisible in normal lymph node
Macrophages (histiocytes)• Phagoctytic cells of lymph node
• Tingible body macrophages of germinal
centers
• Medullary and subcapsular sinus
macrophages• Abundant pale cytoplasm
• Oval nucleus, single small nucleolus
Pathology of lymph nodes 1
Infections
Reactive hyperplasias
Sarcoidosis
Metastatic tumors
Malignant lymphomas
Non-Hodgkin’s lymphoma-NHL
Hodgkin’s lymphoma
Pathology of lymph nodes 2
Infections
Bacterial
• Acute inflammation, abscess formation
Granulomatous, caseous and noncaseous
Diagnosis by culture, serologies, and/or special stains
Reactive hyperplasias
Exaggerations of normal histology.
Expansion of all regions or selective expansion
Some types characteristic of certain diseases, but most not
Follicular hyperplasia- increase in number and size of germinal centers,
spread into paracortex, medullary areas
Collagen vascular diseases
Systemic toxoplasmosis
Syphillis
Interfollicular hyperplasia- paracortex
Skin diseases
Viral infections
Drug reactions
Sinus histiocytosis- expansion of the medullary sinus histiocytes
Adjacent cancer
Infections
Malignant lymphomas
(Non-Hodgkin's lymphomas-NHLs)
Malignancies of the lymphoid system which primarily
manifest themselves outside the bone marrow, at the sites
of normal lymphoid homing
Lymph nodes
Spleen
M.A.L.T.
Anywhere
(Lymphomas outside lymph nodes and spleen are
referred to as extranodal lymphomas)
Approximately 40, 000 cases per year, 20,000 deaths
Clinical presentation
Enlarging mass(es), typically painless, at sites of nodal tissue
Compression, infiltration of hollow organs
Pain, obstruction, perforation
Interference with normal organ function
Solid organ infiltration- kidneys, liver, bone marrow
Systemic symptoms
Fever
Night sweats
Weight loss
If marrow infiltrated, can have leukemic component
NHL 2
Composed of cells that have lost the ability to pursue the full
range of lymphoid differentiation, and are frozen at a single
stage of the normal maturation/differentiation sequence
Recapitulate the biology and immunophenotype of normal cell
counterpart
Several cytologically and immunologically recognizable stages
of normal lymphoid maturation --> several subtypes of
lymphoma
Clonal malignancies, derived from a single cell that has
undergone a malignant transformation, mutation
Best initially conceptualized as two major clinical types
Indolent lymphomas
Aggressive lymphomas
NHL 3 Indolent lymphomas
Lymphomas frozen at stages not normally replicating, but
may be circulating
Diseases of slow accumulation, due to defective apoptosis
Often widespread at diagnosis
Prolonged natural history, median survivals >5 years
Will usually respond to chemo- or radiation therapy
Will usually relapse, but respond to same or alternative tx
Currently incurable unless
Localized disease or
Marrow ablation with some type of stem cell transplant
Classification of indolent lymphomas- later
Aggressive lymphomas
Lymphomas frozen at stages characterized by replication and
accelerated growth
Diseases of defective cell cycle control
More often localized at presentation than indolent lymphomas
More often extranodal
Shorter natural history; median survival </= 2 years
Require more aggressive therapy to achieve "clinical
remission"- disappearance of all detectable disease
Despite short natural history, curable disease in some with
aggressive therapy
Approximately 30-40% of adults
50-80% children
All childhood lymphomas of this type
Classification of lymphomas
Subtyping or classification within the two groupings necessary,
because different subtypes have
Distinct clinical presentations
Can require different therapy
Have differing prognoses, reflecting different mechanisms of
molecular pathogenesis.
Unfortunately, rarely unanimous acceptance of any one
classification scheme.
Intermittent upgrading of classification, with new terminology,
reflecting new information and classifier bias
Classification often lags behind advances in immunology, research
pathology
Final result:
Difficult area to teach
Difficult to remember
Job security for me
WorkingFormulation for
Clinical Usage
• Low grade
From 1982-1994, the classification used
in the United States
Based on:
The observed clinical history of
1200 patients classified according to
the terminology to right
Microsopic examination alone,
utilizing
• Loss of normal nodal
architecture
• The dominant cytologic cell
type observed under the
microscope
• Presence or absence of
"follicularity" - mimicking of
normal lymphoid follicle
formation
• ML, small lymphocytic
• ML, follicular small cleaved cell
• ML, follicular, mixed small and large
cell
• Intermediate grade:
•
•
•
•
ML, follicular, large cell
ML, diffuse, small cleaved cell
ML, diffuse, mixed small and large cell
ML, diffuse, large cell
• High grade
• ML, immunoblastic
• ML, lymphoblastic
• ML, small non-cleaved cell (Burkitt's vs
non-Burkitt's)
• Miscellaneous (mycosis fungoides,
true histiocytic, etc.)
Working Formulation
Divided into three "grades" of lymphoma- low, intermediate and
high. As stated above,
Low grade = indolent
Intermediate and high = aggressive
Limitations
Purely morphologic classification mixed T and B cell
lymphomas together
Lumped distinct subtypes of B cell lymphomas together
Obscured the biologic, clinical and therapeutic differences
Distorted interpretation of clinical trials
R.E.A.L./W.H.O. Classification
WF replaced in 1994 by the Revised European American Lymphoma
(REAL) classification, now being modified by the World Health
Organization (WHO)
REAL/WHO is a "disease” oriented rather than purely morphology
oriented classification, based on:
Cell lineage: B v T v NK v Histiocytic
Stage of maturation of the presumed normal counterpart.
Includes immunologic and molecular criteria in addition to purely
morphologic criteria of WF
Each disease entity may have differing grades of aggressiveness
Greatly expanded the list of entities; includes leukemias of
lymphoid origin
Made teaching to medical students (and in fact all physicians) even
more difficult than WF
REAL contained a number of “provisional entities” which have been
clarified in the upcoming W.H.O. revision.
B-C ell N e op lasms
P recu rso r B -ce ll ly m phob last ic
T /NK-C ell N e op lasms
P recu rso r T ce ll ly m phob last ic
Hodg ki n' s L ym pho ma
Ly m phocyte p redo mi nance,
leuke mi a/ ly m pho m a
leuke mi a/ ly m pho m a
nodu la r
Pe ri phe ra l B -ce ll neop las m s
Pe ri phe ra l T- ce ll and N K -ce ll
neop las m s
Pre do mi n a nt ly
le u kemic/ d issemi n a te d
T- ce ll p ro ly m phocyt ic leuke mi a
T- ce ll l a rge g ranu la r ly m phocyt ic
Cl ass ica l H L
B -ce ll C LL/SLL
B -ce ll p ro ly m phocyt ic leuke mi a
Ly m phop las m acyt ic ly m pho m a
M ant le ce ll l y m pho m a
F o lli cu la r l y m pho m a
Ext ranoda l m a rg ina l zone B ce ll l y m pho m a, M AL T type (+ /m onocyto id B ce ll s )
N oda l m a rg ina l zone B -ce ll
ly m pho m a (+ /-m onocyto id B
ce ll s )
Sp len ic m a rg ina l zone B -ce ll
ly m pho m a (+ /-v ill ous
ly m phocytes )
H a ir y ce ll l euke mi a
Di ffuse la rge B -ce ll l y m pho m a
Bu rk itt ly m pho m a
P las m a ce ll m ye lo m a
P las m acyto m a
(LGL ) l euke mi a
N K ce ll l euke mi a
Adu lt T- ce ll l euke mi a/ ly m pho m a
Pre do mi n a nt ly nod al
Ang io imm unob last ic T- ce ll
ly m pho m a
Pe ri phe ra l T- ce ll l y m pho m a
unspec ified
Anap last ic la rge ce ll l y m pho m a,
T /nu ll- ce ll
Pre do mi n a nt ly ex tra nod al
M ycos is fungo ides
Seza ry synd ro m e
P rim a ry cutaneous
(CD 30 + T- ce ll
ly m phop ro li fe rat ive d iso rde rs )
Subcutaneous
pann icu li tis -li ke Tce ll l y m pho m a
N K/ T ce ll l y m pho m a, nasa l and
nasa l- type
Ente ropathy -type intest ina l T- ce ll
ly m pho m a
H epatosp len ic T- ce ll l y m pho m a
g/d (ga mm a/de lta )
a /b (a lpha/beta )
Ly m phocyte
ri ch c lass ica l H L
N odu la r sc le ros is
Mi xed ce ll u la ri ty
Ly m phocyte dep
let ion
U nc lass ifiab le c lass ica l H L
REAL/WHO classificationbackbone
B cell neoplasms
Precursor B cells-related to acute leukemia
Peripheral B cell lymphomas- the majority of B
cell lymphomas
T cell and Natural Killer cell neoplasms
Precursor T cells
Peripheral T cell and NK neoplasms
Hodgkin’s lymphoma
Frequency of lymphomas
Indolent versus aggressive
Indolent
Small lymphocytic
lymphoma/CLL
Follicular lymphoma, Grades
1/2
Extranodal Marginal zone
lymphoma of MALT type
Nodal marginal zone
lymphoma
Splenic marginal zone
lymphoma
Hairy cell leukemia
Lymphoplasmacytic
lymphoma
Plasma cell myeloma
Plasmacytoma
Cutaneous T cell lymphoma
Cutaneous CD30+ anaplastic
large cell lymphoma
Aggressive
Prolymphocytic
leukemia
Large B cell lymphoma
Burkitt lymphoma
Mantle cell lymphoma
Anaplastic large cell
lymphoma
All peripheral T cell
lymphomas
Divides B and T
B cell neoplasms- Precursor B
Precursor B cell lymphoblastic leukemia/lymphoma
Frozen at lymphoblast cell stage of antigen
independent B cell differentiation- normally restricted
to bone marrow
Usually present as acute leukemia +/- lymph node
involvement
Can initially present as node or skin disease, with later
progression to bone marrow
Treated as acute leukemia
• 80% cure rate in children
• 20-30% in adults because of "bad" cytogenetics:
frequent presence of Philadelphia chromosome
t(9;22)
Peripheral B-cell lymphomas
Lymphomas frozen at various stages of antigen dependent B cell maturation and
differentiation
Peripheral B-cell neoplasms
Frozen at various stages of antigen dependent B cell maturation and
differentiation
Small lymphocytic/CLL- the virgin B cell fresh from the marrow
Prolymphocytic leukemia- a more clinically aggressive variant of above
Lymphoplasmacytic lymphoma- the primary immune response
Mantle cell lymphoma- the mantle region surrounding the follicle
Follicular lymphoma- the follicle- grades 1-3
Extranodal marginal zone lymphoma- cells at the periphery of the follicle in
extranodal sites of lymphoid tissue- Mucosal Associated Lymphoid tissuesuch as G.I. tract
Nodal marginal zone lymphoma
Splenic marginal zone lymphoma- immunologically distinct
Hairy cell leukemia- pre-plasma cell
Diffuse large B-cell lymphoma- this breaks the ideal of specific cell stage
but all represent lymphomas with high replication rate
Burkitt lymphoma- very aggressive
Plasma cell myeloma- diffuse bone marrow proliferation of plasma cells
Plasmacytoma- solitary focus of monoclonal plasma cells, with variable
risk of progression to myeloma, depending on site
Example Indolent Lymphoma:
Follicular lymphoma Grade I
Clinical
Most common type of indolent lymphoma in
US; second most common type lymphoma
overall
Disease of adults >40 (median age 59)
Usually widely disseminated at diagnosis,
incl. bone marrow
Will respond to “gentle chemotherapy” but
will relapse
• Incurable short of bone marrow
transplant unless rare limited disease
Overall 5 yr survival 72%
Over time, additional mutations -->
progression (“transformation”) to large cell
lymphoma --> aggressive clinical course
Although Gr.1 is most common presentation,
some patients present with predominance of
large cells within follicles -->more aggressive
clinical course
Pathogenesis:
Due to t(14;18)(q32, q21)
• Upregulates expression of an antiapoptotic protein Bcl2
• Immortalizes lymphoma cells
Follicular lymphoma Grade I
Pathology/diagnosis
Benign equivalent: small cleaved cell
of germinal center
Clumped chromatin and infrequent
nucleolus like small lymphocyte
Irregular nuclear profile, with nuclear
folds or "cleavages"
Retain follicular structure, but
monotonous accumulation of single
cell type
Characteristic immunophenotype:
• Positive:Monoclonal light chain,
CD19, CD10, Bcl2
• Negative: CD5, Cyclin D1/Bcl1
Can also detect translocation by
cytogenetics and/or polymerase chain
reaction
T a b le X : Ind o le n t B ce ll ly m p ho mas
F ol licu lar
L ym phom a
(G rade I)
22 %
M arg ina l zo ne
L ym phom a
S ma ll ly mp ho cy tic
ly mp homa/ CL L
8
7
A ge of on s et
m ed ian
59
61
65
S tage at
P re s e ntat ion
S tage III/I V
Diss em in ated
S tage I
S tage IV
R e s po ns e to
T hera py
Goo d to m o s t
tr eatme nts ,
but inc ura bl e
s ho rt of
tr an s p lant
72 %
F requ ent ly
c u rab le
Si m ilar t o
F ol licu lar
ly mp homa
74 %
51 %
P red om inan t si te
p re s enta tion
N oda l
Ex tran o da l
M arro w /noda l
P atte rn of noda l
Inf iltrat ion
F ol licu lar
Di ffu s e
Di ffu s e
B en ign cel l
E qu iv a len t
Ge rm ina l
c ent e r
s m all cle a v ed
c e ll
S ma ll cl ea ve d
c e ll i n m o s t
c a s e s , but c a n
be la rge cel l
P o si tiv e: CD 19
CD 10 , Bcl 2 +
N ega tive : CD 5 -
M arg ina l zo ne
L ym pho cy te
Vi rg in B c e ll
M ix o f s ma ll
ly mp ho cy te s ,
p la sm a c e lls
t( 14;18 )
Bcl 2/ JH
t( 11;18 ),
T ris om y 3
S ma ll
ly mp ho cy te s
wi th round
nu cl e us
P o si tiv e:
CD 19, CD 5
CD 23
N ega tive :
CD 10
T ris om y 1 2
F requ en cy (%
a ll ly m phoma s
5 y r s u rvival
D om inant c e ll
ty pe
Im m uno pheno
-t yp e
M olec u lar
P atho gene sis
P o si tiv e:
CD 19, Bcl 2
N ega tive :
CD 10, CD 5
Examples: aggressive B cell lymphomaDiffuse large B cell lymphoma
Clinical
Most common lymphoma- 30% NHL
Disease of adults and children, but median age 64
Limited versus widespread disease ~1:1
Presents with rapidly enlarging masses
Approximately 40% curable with aggressive chemotherapy/
stem cell transplant
• Partially predictable by International Prognostic Index
(later)
Pathogenesis
Not as clearly defined as previous examples- several
cytogenetic abnormalities associated with large cell
lymphoma, but no defining one
Diffuse Large B cell lymphoma
Pathology
Benign equivalent- large replicating B
cells of germinal center and
paracortex
Diffuse infiltration of lymph node
Often necrosis; increased mitotic rate
Cytology: Oval or cleaved nucleus with
vesicular chromatin and 1-3 nucleolus
Nucleus larger than that of reactive
macrophage
Several cytologic subtypes initially felt
to have differing clinical behavior.
Yielded division into intermediate
versus high grade types- now not felt
valid or significant without
immunologic/molecular evidence
Immunophenotype characterized by
monoclonal light chain, CD19
expression,with variable expression of
other B cell associated antigens
Burkitt's lymphoma
Clinical
3% lymphomas
Disease of adults and childrenmedian age 31
Initially recognized in Africa by
Thomas Burkitt
• Association with Epstein Barr
virus infection
• Localization in jaw
In US, usually presents in ileocecal
region of children
1/3 of all childhood lymphomas
Earlier eras, very aggressive and
rapidly fatal
• Now, ~70-80% children curable
• 40% of adults
Pathogenesis:
t(8;14), producing upregulation of
myc oncogene, a cell cycle
regulation gene
Burkitt's lymphoma
Pathology
Benign equivalent is replicating small
noncleaved cell of germinal center:
Diffuse infiltration of lymph node
Very high mitotic rate, lot of
ineffective proliferation;
Attracts macrophages to
phagocytize> starry sky pattern at
low power
Cytology: round nucleus, smaller
than that of reactive macrophage
Vesicular chromatin and 2-5 nucleoli
Immunophenotype:
• Positive: Monoclonal light chain,
CD19, CD10
• Negative: CD5
Mantle cell lymphoma
Clinical
6% lymphomas
Disease of adults (median
age 63)
Usually widely disseminated
Poor response to all
attempted therapies,
? curable with transplant
5yr survival 27%
Pathogenesis
Due to t(11;14)
Upregulates Bcl1 (cyclin
D1), a cell cycle regulator
Mantle cell lymphoma
Pathology/Diagnosis
Benign equivalent is lymphocyte of
inner mantle zone
Cytology similar to cleaved cell, but
nuclear irregularities not as
prominent
Nodal infiltration diffuse, vaguely
nodular or "mantle zone" around
residual benign follicles
Large cell progression infrequent
Immunophenotype:
• Positive: monoclonal light
chain, CD19, CD5, Bcl1 (and
Bcl2)
• Negative CD10, CD23
Follicular lymphoma
Mantle cell lymphoma
CyclinD1
Bcl2
T a b le X : Ind o le n t B ce ll ly m p ho mas
F ol licu lar
L ym phom a
(G rade I)
22 %
M arg ina l zo ne
L ym phom a
S ma ll ly mp ho cy tic
ly mp homa/ CL L
M ant le c e ll
L ym phom a
8
7
6
A ge of on s et
m ed ian
59
61
65
63
S tage at
P re s e ntat ion
S tage III/I V
Diss em in ated
S tage I
S tage IV
S tage III/I V
R e s po ns e to
T hera py
Goo d to m o s t
tr eatme nts ,
but inc ura bl e
s ho rt of
tr an s p lant
72 %
F requ ent ly
c u rab le
Si m ilar t o
F ol licu lar
ly mp homa
P oor re s po ns e to
a ll th erap ie s
to date
74 %
51 %
27 %
P red om inan t si te
p re s enta tion
N oda l
Ex tran oda l
M arro w /noda l
N oda l
P atte rn of noda l
Inf iltrat ion
F ol licu lar
Di ffu s e
Di ffu s e
B en ign cel l
E qu iv a len t
Ge rm ina l
c ent er
s m all cle a v ed
c e ll
S ma ll cl ea ve d
c e ll i n m o s t
c a s e s , but c a n
be la rge cel l
M arg ina l zo ne
L ym pho cy te
Vi rg in B c e ll
Di ffu s e,
no du lar
or
Òm ant le zo neÓ
M ant le c e ll
M ix o f s ma ll
ly mp ho cy te s ,
p la sm a c e lls
S ma ll
ly mp ho cy te s
wi th round
nu cl e us
F requ en cy (%
a ll ly m phoma s
5 y r s u rvival
D om inant c e ll
ty pe
Im m uno pheno
-t yp e
P o si tiv e: CD 19 P o si tiv e:
CD 10 , Bcl 2 +
CD 19, Bcl 2
N ega tive : CD 5 - N ega tive :
CD 10, CD 5
M olec u lar
P atho gene sis
t( 14;18 )
Bcl 2/ JH
T ris om y 3
P o si tiv e:
CD 19, CD 5
CD 23
N ega tive :
CD 10
T ris om y 1 2
S ma ll c e ll
wi th irregu la r
nu cl e us ,
si m ila r to
cl ea v e d
P o si tiv e:
CD 19, CD 5 ,
Bcl 2
N ega tive :
CD 10
t( 11;14 )
Bcl 1/ JH
T cell lymphomas-Precursor T
Clinical
Disease of teenagers; boys>girls
Can present as acute leukemia or mediastinal mass+/- marrow
involvement
Aggressive lymphoma/leukemia, but curable: ~70% with
appropriate multiagent chemotherapy
Pathogenesis
No single gene culprit, but frequently involve translocation of
(onco)genes to site of T cell receptor genes, --> upregulation of
proteins
T cell lymphomas-Precursor T
Pathology
Benign equivalent
immature T cells of
thymus
Histology: Diffuse
infiltration of
thymus/adjacent lymph
nodes
Cytology: “Blast cells”
of intermediate size with
oval to “convoluted”
nuclear profiles, fine
chromatin and 0-1
nucleolus
Again need immunology
to distinguish from pre-B
Peripheral T cell lymphomas
Predominantly
leukemic/disseminated
T-cell prolymphocytic
leukemia
T-cell large granular
lymphocytic (LGL) leukemia
NK cell leukemia
Adult T-cell
leukemia/lymphoma
Predominantly nodal
Angioimmunoblastic T-cell
lymphoma
Peripheral T-cell lymphoma
unspecified
Anaplastic large cell
lymphoma, T/null-cell
Predominantly extranodal
Mycosis fungoides
Sezary syndrome
Primary cutaneous CD30+ Tcell lymphoproliferative
disorders
Subcutaneous panniculitislike T-cell lymphoma
NK/T cell lymphoma, nasal
and nasal-type
Enteropathy-type intestinal Tcell lymphoma
Hepatosplenic T-cell
lymphoma
Key points regarding T cell
lymphomas
Clinical
Pathology
Represent 20% all lymphomas
Cytologic features not as predictive of
behavior as B cell lymphomas
More often extranodal than B
• Anaplastic large cell lymphoma
• Can involve skin, midline facial
--> better prognosis than most
area, liver
indolent B cell lymphomas- 77% 5
• Very characteristic clinical
year survival
presentations
• Mycosis fungoides, indolent
Most diseases bad: high stage,
cutaneous lymphoma, incurable, but
and poorer response to therapy
with long clinical course
than B cell lymphomas of all
Immunophenotypic studies frequently
grades
demonstrate
Pathogenesis:
• Loss of normal T cell associated
Characteristic cytogenetic findings
antigens
associated with several types
• Antigens associated with Natural
• Anaplastic large cell
Killer cell function
lymphoma- t(2;5): ALK1 gene
• Immunology absolutely necessary to
• Hepatosplenic T cell
recognize
lymphoma- Isochromosome 7
Ancillary diagnostic studies
Use of immunologic/molecular techniques
Malignant lymphomas reproduce the immunobiology of their
benign counterparts
This reproduction may be aberrant, and hence distinguishable
from normal
Expression, normal and aberrant can be used to:
Determine lineage, B versus T versus NK
Detect clonality
Suspect malignancy- loss or aberrant expression of
expected antigens
Recognize characteristic patterns of antigenic expression
associated with certain subtypes of lymphoma
Normal lymphoid maturation
Requires two major activities
The production of a unique
antigenic receptor on it's
surface
The expression of several
surface proteins necessary for
antigen recognition, cell
activation, cell-cell
communication.
Antigen receptors are
generated through the process
of "genetic rearrangement"- the
random selection and
juxtaposition of discontinuous
genetic segments encoding the
antigen receptor genes
B cells
• Immunoglobulin receptor
composed of two heavy
and two light chains
– Select specific heavy
chain antigen
recognition sequence
– Select only one of two
light chains, kappa or
lambda
T cells
• Select one of two
heterodimeric receptors
– Alpha/Beta
heterodimer T cell
receptor
– Gamma/Delta
heterodimer T cell
receptor
Normal lymphoid maturation
Requires two major activities
The production of a unique antigenic receptor on it's surface
The expression of several surface proteins necessary for antigen
recognition, cell activation, cell-cell communication.
Antigen receptors are generated through the process of "genetic
rearrangement"- the random selection and then juxtaposition of
discontinuous genetic segments encoding the antigen receptor genes
B cells
• Immunoglobulin receptor composed of two heavy chains and
two light chains
– Select specific heavy chain gene sequences
– Select only one of two light chains, kappa or lambda
T cells
• Select one of two heterodimeric receptors
– Alpha/Beta heterodimer T cell receptor
– Gamma/Delta heterodimer T cell receptor
Antigen receptor selection- B cell
Surface antigen production
Immune cells require numerous surface molecules for
effective immune response, cell-cell communication and
regulation
Classified into B cell associated, T cell associated, activation
associated, cytokine receptors
Expression occurs in an orderly sequence in lymphoid
maturation
Antibodies to these molecules cataloged thru the CD clusters of differentiation - numerical system
Initially developed to characterize monoclonal antibodies
detecting proteins whose function was unknown .
Now up to CD166. You'll only be tested on 1-130 though
(- a joke for you paranoid types.)
B cell antigen expression
T cell antigen expression
Immunologic Techniques
Flow cytometry-automated
fluorescent microscopy
Immunohistochemistry- in situ
immunologic detection
through the use of enzyme
substrate color deposition
Both utilize monoclonal
antibodies to detect clonality
and unique antigenic patterns
Immunologic Techniques
Flow cytometry-automated fluorescent microscopy
Immunohistochemistry- in situ detection through the use of
enzyme substrate color deposition
Examples
B cell small lymphocytic lymphoma• Monoclonal light chain, CD19, CD20, CD5, CD23
positive, CD10 negative
B cell follicular lymphoma• Monoclonal light chain, CD19, CD20, CD10
positive, CD5 negative
Molecular techniques
Detection of antigen receptor clonality
Detection of unique cytogenetic
rearrangements/translocations
Examples
Clonal gene rearrangement by Southern blot
Bcl2/JH rearrangement by polymerase chain
reaction
Clinical presentation
Enlarging mass(es), typically painless, at sites of nodal
tissue
Obstruction, ulceration of hollow organs- pain, perforation
Interference with normal organ function
Solid organ infiltration- kidneys, liver, bone marrow
Systemic symptoms
Fever
Night sweats
Weight loss
If marrow infiltrated, can have leukemic component
Clinical staging of lymphomas
Defines extent of disease; determines therapy and prognosis
Based on physical, radiologic examination, bone marrow biopsy and
aspiration
Ann Arbor Staging system
B symptoms- fever, weight loss > 10% body weight, night sweats
Staging table
Prognosis
International prognostic index
Aggressive lymphomas
Cytogenetics
Oncogenes
International Prognostic Index 1
Clinical features
identifying prognostic
subsets of diffuse
large cell lymphoma
Identified through
retrospective
statistical analysis of
large set patients
Assigned 1 point for
each bad feature
Survival curves
Therapy I Indolent lymphomas
Seminar cases will also discuss
Limited stage (5-10% cases)
Radiation therapy
Can be curative
Disseminated indolent/low grade lymphomas (90%)
No therapy
Low morbidity limited chemotherapy
• Older patients
• No expectation of cure
• Most will respond totally or partially, with
months to years of disease free survival,
but will relapse
• Many will respond to additional rounds of
similar or alternative regimens
• Pts will die of disease, or interceding
disease of elderly
• Death from disease due to
– Immune suppression- infections
– Progression to aggressive lymphoma
"Bone marrow transplant"• Effort at cure
• Reserved for younger patients <60
• High dose chemotherapy and
allogeneic transplantation
• High dose chemotherapy and
autologous peripheral stem cell
collection/reinfusion
• Increased morbidity
Therapy II- Aggressive
lymphoma
Limited disease localized disease treated with irradiation
plus limited cycles multiagent chemotherapy
More extensive disease with more cycles multiagent (>/= 4
drugs) chemotherapy
Complete remission rates 60-80%
30-40% cured
Newer therapies and their roles still being established
Bone marrow transplantation
• Allogeneic
• Autologous
Immunotherapy
Hodgkin's lymphoma
Less common than NHL; ~
10,000 cases per year
Age incidence bimodal, with one
peak in late adolescence, young
adulthood, second peak
beginning in sixth decade
Bimodal curve shifts to
younger ages in poorer
countries
Unlike NHL, HL diagnosed by
the presence of a minor cellular
component, the ReedSternberg cell, found in the
appropriate microscopic cellular
background
Hodgkin's lymphoma
classification
R ye C la s sifi c atio n
L y mpho c yt e pr e domi n ant -5 %
R E A L/W HO C la s sifi c ati o n
L y mpho c yt e pr e domi n anc e ,
nod u la r
N odu la r sc le ro s is -7 0 %
M ixed c e llu lar ity -20 %
L y mpho c yt e depl e ted -5 %
C la ss ic a l H L
L y mpho c yte rich cl a ss ic al H L
N od u la r sc le ro s is
M ixe d ce llu la rity
L y mpho c yte dep letio n
U n c la s sifiab le c la s sica l H L
Hodgkin's Histologic subtypes
Are characteristic patterns of
involvement, and characteristic
variants of Reed Sternberg cell
associated with different subtypes
Nodular sclerosing HL
Most common type Hodgkin's
lymphoma in US/Europe
Usually presents in the anterior
mediastinum and neck of young
adult females
Characterized by fibrotic capsule
and bands subdividing tissue and
Lacunar variant Reed Sternberg
cell
Histologic
subtypes 2
Lymphocyte predominant
Usually presents with limited disease in the
neck of young adults
Associated with L and H (lymphocytic and
histiocytic) or "popcorn cell" variant RS cell
Mixed cellularity
More extensive disease
Older patients than NS and LP
More R-S cells, eosinophils, plasma cells
Mononuclear variant R-S cells
Inherently more aggressive disease
Lymphocyte depleted
Often presents in retroperitoneum, older
patients
Accompanied by loss lymphocytes,
sclerosis and pleomorphic RS cell variants
Also more aggressive disease
Ancillary studies
Ancillary immunologic studies assist the dx of Hodgkins' lymphoma
Distinguish HL from
Immunoblast reactions
Unusual variants of NHL
CD15 and CD30 antigens in golgi and on cell membrane of R-S cells
most useful
Patterns of spread
Hodgkin's lymphoma spreads contiguously via
lymphatics
Staging as in NHL- may or may not include
laparotomy/splenectomy
Therapy
Limited stage, low bulk disease treated with
radiation therapy
Higher stage, B symptoms (IIB-IV) treated with
multi-agent chemotherapy+/- radiation therapy
Complications of therapy
Radiation effects to lungs, heart, bone marrow
Sterility
Splenectomy associated sepsis
Therapy associated second malignancies
Prognosis
Hodgkin's lymphoma is a curable malignancy
Overall cure rate approximately 80%
With modern therapy, prognosis based more on
staging, bulk of disease, than morphologic subtype
Not true in earlier era, where prognosis decreased
with number of lymphocytes; lymph depleted HL
had a terrible prognosis
Pathobiology
The etiology of HL is still unknown
The lineage of the R-S cell was also obscure until recently
The mixed cellular infiltrate, unusual large cells, clustered familial
cases, and early evidence of immune dysfunction suggest an infectious
etiology+/- an inherited predisposition
In approximately 30% of cases, Epstein Barr virus found within the RS
cells
Molecular studies, utilizing single cell dissection and PCR based
sequencing of the antigen receptor genes indicate that the R-S cell in
the majority of cases is an altered B cell.
Thus HL is a type of B cell lymphoma, but with a very different
biology from the other types of B cell lymphoma
Still deserves a separate category in the classification system
Molecular information
The molecular abnormalities within the different types of
R-S variants effect the expression of lineage associated antigens
L and H cells of lymphocyte predominant HL express B cell
antigens, and are clonal proliferations of this cell type
RS cells of other types may express T cell, B cell and macrophage
associated antigens, but usually fail to express antigen receptors
• At the molecular level, show B cell gene rearrangements with out of
frame mutations or.
• Mutations in transcription/translation systems so no antigen receptor
proteins transported to surface
The End!
Additional figures
Reed Sternberg cells
Large cells