The document discusses various types of cutaneous lymphomas, focusing on primary and secondary forms, and the distinct behaviors and characteristics of T-cell and B-cell lymphomas. It elaborates on diagnostic criteria, clinical features, and histopathologic presentations for conditions like mycosis fungoides and Sezary syndrome. Additionally, it outlines the immunological responses and migration patterns of lymphocytes within the skin, highlighting the complex nature of these diseases.

1. By- Dr. Kanwalpreet Kaur
Moderator- Dr. Karuna Gupta

2.  PRIMARY LYMPHOMAS- that present in the skin
with no evidence of extracutaneous disease at the time
of diagnosis
 SECONDARY LYMPHOMAS- systemic lymphomas
that secondarily involve the skin.

3.  Differences in adhesive ligands between T and B
cells
 Differential affinity for different compartments
• Benign and malignant T cells migrate to
epidermis and its adnexa.
• This phenomena is known as
EXOCYTOSIS in BENIGN CONDITIONS;
EPIDERMOTROPISM in MALIGNANT
CONDITIONS.
• This pattern may be blunted as tumour
evolves into more aggressive and poorly
differentiated state.
• B cells spare epidermis and
papillary dermis
• Sparing of papillary dermis produces
grenz zone
• innate proclivity of B cells to
aggregate into follicular structures, B-
cell infiltrates in the skin often (but
not invariably) show a nodular
architecture

4. T CELL PATTERN
B CELL PATTERN- GRENZ ZONE
AND GERMINAL CENTRE
FORMATION

5.  In both T- and B-cell responses in skin
circulating lymphocytes initially adhere to activated
endothelium lining dermal postcapillary venules.
PERIVASCULAR/
ANGIOCENTRIC DERMATITIS
Further migration may be
Stunted
e.g. erythema chornium migrans

6.  Migration away from the vessel wall is presumably swift
enough that in the case of T cells
papillary dermal accumulation and epidermotropism, in addition
to a persistent angiocentric pattern
IMMUNOLOGICALLY ACTIVE
T CELLS
1.Produce cytokines and growth factors
so T cell exocytosis is associated with
epithelial spongiosis, acanthosis or
apoptosis
2. seen in contact hypersensitivity,
psoriasis, cytotoxic dermatitis
MALIGNANT EPIDERMOTROPIC
T CELL INFILTRATE
1.Epidermis is passive
2.No reactive epithelial alteration
3.No spongiosis or apoptosis
4.However, epidermal injury in the form
of mucinous degeneration may occur.
5.The epidermis becomes more
extensively infiltrated, impaired
maturation often manifests as clinical
abnormalities in scale production

7. A: Abnormal epidermotropism into a “passive” epidermis.
B: Scaling patches and plaques as a consequence of altered epidermal maturation
associated with T-cell epidermotropism (MF).

8. REACTIVE B CELLS
1) perivascular accumulation of
cells
2) No significant involvement of
papillary dermis or epidermis
3) Grenz zone of papillary
sparing
4) Preservation of archietecture
MALIGNANT B CELLS
1) Destructive relationship to
pre-exsisting structures
2) Infiltatre in interstitial pattern
causing
3) Splaying of collagen bundles
and mesenchymal cells within
reticular dermis
4) This progressive dermal
infiltration+ epidermal
sparing red to plum colored
nodules covered by
nonkeratotic epidermis

9. Normal and abnormal trafficking patterns. A: B-cell pattern showing nondestructive infiltration
of superficial and deep dermis.
B: B-cell lymphomas showing vascular invasion , replacement of subcutis , and diffuse
interstitial pattern .
C: Plum-colored nodule covered by thinned, glistening epidermis due to B-cell dermal
infiltration.

10.  Heterogenous spectrum of lymphoid infiltrates that can
be similar histologically to malignant lymphomas but do
not have clinical presentation or biological outcome of
lymphoma.
 Inflammatory infiltrate is band like, nodular or diffuse
and composed of lymphocytes predominantly, but other
inflammatory cells are also present.
 Depending on the predominant cell type in the infiltrate,
they are divided into T and B cell types.

12. CUTANEOUS T- cell and NK- cell Lymphomas
1. MYCOSIS FUNGOIDES (MF)
2. MYCOSIS FUNGOIDES VARIANTS AND SUBTYPES:
a) Folliculotropic MF
b) Pagetoid reticulois
c) Granulomatous slack skin
3. SEAZARY SYNDROME
4. ADULT T- cell LYMPHOMA
5. PRIMARY CUTANEOUS CD30+ LYMPHOPROLIFERATIVE DISORDERS
a) Primary cutaneous anaplastic large cell lymphoma (cALCL)
b) Lymphomatoid papulosis
6. SUBCUTANEOUS PANNICULITIS LIKE T CELL LYMPHOMA
7. EXTRANODAL NK/T- cell LYMPHOMA, NASAL TYPE
8. PRIMARY CUTANEOUS PERIPHERAL T- cell LYMPHOMA, UNSPECIFIED
a) Primary Cutaneous Aggressive Epidermotropic CD8+ T- Cell Lymphoma
b) Cutaneous γ/ δ T- Cell Lymphoma
c) Primary Cutaneous CD4+ Small/Medium Sized Pleomorphic T- Cell Lymphoma

13. CUTANEOUS B-cell LYMPHOMAS
1. Primary cutaneous follicle centre lymphoma
2. Primary cutaneous marginal zone B-cell lymphoma
3. Primary cutaneous diffuse large B-cell lymphoma, leg type
4. Primary cutaneous diffuse large B-cell lymphoma , other
5. Intravascular large B-cell lymphoma
PRECURSOR HEMATOLOGIC NEOPLASM
CD4+/CD56+ hematodermic neoplasm (blastic NK cell lymphoma)

14.  Low grade epidermotropic T-cell lymphoma
 Mycosis fungoides is relatively rare, accounting for less than
1% of non-Hodgkin lymphomas. However, of lymphomas
that arise primarily in skin, it is the most common
 Peak age 55-60
 Male: female 2:1

15.  Typically begins as slowly progressive dermatitis-like patches
and plaques on non sun-exposed skin, and when untreated
evolves to nodules and eventual systemic dissemination
Lesions initially -erythematous scaling
patches and plaques that typically are
resistant to antiinflammatory therapy;
Large with polygonal or arcuate
configurations;

16. Plaques and nodules of
advanced disease which may
eventually ulcerate

17. • When extracutaneous spread eventuates, lymph nodes, spleen, liver,
and lungs are often involved, in addition to the peripheral blood.
• Bone marrow involvement is rare
• Lymph node enlargement at such advanced stages must be
differentiated from nodal hyperplasia resulting from chronic
drainage of involved sites (dermatopathic lymphadenopathy)
• Progression to Extracutaneous disease correlates with extent of skin
disease
• A) Limited patch or plaque- very rare
• B) Generalized plaque- 8 %
• C) Tumorous or generalized erythroderma-30-40% Hence,
extracutaneous is more commonly seen in Sezary syndrome.

18.  Atypical SMALL to MEDIUM sized mononuclear
neoplastic T cells with cerebriform nuclei infiltrating the
upper dermis among epidermal keratinocytes
(epidermotropism) forming intra epidermal aggregates
(Pautrier microabscesses), or arranged in linear fashion
just above the basement membrane.
 Pautriers abscesses – pathognomonic but present only in
38 % cases of MF
 Minimal epidermal spongiosis typically present
 Lymphocytes aligned within the basal layer

19. 1.Patch stage: superficial band-like or lichenoid infiltrate,
mainly lymphocytes and histiocytes, but also a few atypical cells
(small/medium-sized, cerebriform nuclei, halo) usually confined
to the epidermis (basal layer)= EPIDERMOTROPISM
2.Plaque stage: more pronounced epidermotropism with
occasional characteristic intraepidermal collections of atypical
cells (Pautrier microabscesses)
3. Tumor stage: more dense nodular or diffuse dermal infiltrate,
may lose epidermotropism, more size and shape variability of
tumor cells, histologic transformation to large cell phenotype
may occur (>25% large lymphoid cells in the dermal infiltrate)

20. Papillary dermal interstitial
infiltrate associated with
linear aggregation of
neoplastic lymphocytes
along the dermal-epidermal
junction
CD4 Staining
emphasizing this linear
pattern of early
epidermotropism

21. Plaque-stage disease -prominent clusters of
atypical lymphocytes within the epidermis
(Pautrier microabscesses)

22.  CD2+, CD 3+ , CD 5+, CD4+, CD8-, CD 7- and usually
CD 30-

CD 4 STAINING CD 8 STAINING

23.  Clonal T-cell receptor( TCR) gene rearrangements
have been detected (mostly alpha/beta, rarely
gamma/delta receptors)
 Increased rate of aberrations involving multiple
chromosomes 1,6,11,8,17,15,13, and 9 in advanced
stage disease

25.  ISCL/EORTC Diagnostic algorithm :
 Point based system
 A total of 4 points is required for the diagnosis of
MF based on any combination of points from the
clinical, histopathologic, molecular biological, and
immunopathologic criteria.

26. CRITERIA MAJOR
(2points)
MINOR
(1 point)
CLINICAL
Persistent and/or progressive patches and plaques
plus
Any2 Any 1
a) Non sun exposed areas
b)size/shape variation
c)Poikiloderma
HISTOPATHOLOGIC
Superficial lymphoid infiltrate plus Both Either
a)Epidermotropism without spongiosis
b) Lymphoid atypia
MOLECULAR BIOLOGICAL:
clonal TCR gene rearrangement
present
IMMUNOPATHOLOGIC:
a) CD 2,3,5 < 50% of T cells Any one
b) CD7< 10% T cells
c) Epidermal discordance from expression of
CD2,3,5 or CD 7 on dermal T cells

27. SKIN
T1- limited patches, plaques and /or plaques covering < 10% of skin surface
T2- patches, papules or plaques covering 10% or more skin surface
T3- one or more tumours (>1cm)
T4- confluence of erythema covering 80% or more of body surface area
NODE
N0- no clinically abnormal peripheral lymph nodes
N1- clinically abnormal peripheral lymph nodes; histopathologically Dutch
grade 1 or NC1 LN0-2
N2- clinically abnormal peripheral lymph nodes; histopathologically Dutch
grade 1 or NC1 LN0-2
N3- clinically abnormal peripheral lymph nodes histopathology dutch
grades 3-4

28. VISCERAL
M0- no visceral organ involvement
M1- visceral involvement
PERIPHERAL BLOOD INVOLVEMENT
B0- absence of significant blood involvement:5% or less of peripheral
blood lymphocytes are atypical
B1- low blood tumour burden:>5% of peripheral blood lymphocytes are
atypical
B2- high blood tumour burden: 1000/microl sezary cells

29.  It is characterised by – usual type of cells seen in
epidermotropic forms of mycosis fungoides but is
confined to hair follicles and is associated with
follicular mucinosis.
 CLINICAL FEATURES- slowly enlarging follicular
patches or plaques on head and neck ; may be associated
with alopecia
 WORSE PROGNOSIS compared to other variants and
require aggressive therapy

30. Folliculocentric infiltrate with
mucinous expansion of the follicle.
Infiltrate is usually monomorphic containing cerebriform CD4+ Lymphocytes

31.  Rare and peculiar form of mycosis fungoides
 CLINICAL FEATURES- solitary acral lesion in the
form of verrucous plaque that does not progress
clinically
 If multiple lesions are present / widely disseminated in
skin- KETRON-GOODMAN type  should not be
considered pagetoid reticulosis but primary cutaneous
aggressive epidermotropic CD8+ cytotoxic T-cell
lymphoma

32. -exclusively epidermal
infiltration
-INFILTRATE-
mononuclear convoluted T
cells
-pagetoid pattern with or
without intraepidermal
nests
- Epidermal hyperplasia
- hyerkeratosis
Mixed infiltrate of non neoplastic lymphocytes and histiocytes may be seen in
superficial dermis

33.  CD3+, CD4+, CD8- or CD3+, CD4-, CD8+
 MOLECULAR GENETICS
 Clonal TCR gene rearrangements

34.  Extremely rare subtype
 CLINICAL FEATURES- slowly developing zones
of lax skin in the axillae and inguinal regions;
occurs predominantly in men
 Good prognosis

35. Diffuse mononuclear infiltrate+
macrophages+multinucleate giant
cells+ T cells with convoluted
nucleus. Elastolysis seen in
dermis.

36.  Potentially aggressive form
 These malignant T cells have phenotypic and antigenic
overlap with those of mycosis fungoides, Sezary
syndrome is sometimes regarded as a mycosis fungoides
variant. However, important clinical and
histopathologic differences exist between classical
mycosis fungoides and Sezary syndrome
Generalized redness and scaling of the skin (erythroderma)
+lymphadenopathy + presence of malignant convoluted T cells
(sezary cells) in the skin, lymph nodes and peripheral blood

37.  Diffuse skin erythema and lymphadenopathy. There may also
be itching, hair loss, nail dystrophy, and hyperkeratosis
affecting the skin of palms and soles

 In addition to lymph node, skin, and blood involvement,
malignant T cells may also infiltrate viscera in late stages,
although bone marrow is often spared

38. band-like papillary dermal
lymphoid infiltrate;
Lack epidermotropism:
More monomorphic cells

39. dense perivascular and superficial
dermal atypical lymphoid
infiltrate with minimal focal
epidermotropism.

40.  LYMPH NODES- effacement of their architecture by
atypical cells infiltrates
 PERIPHERAL BLOOD-atypical lymphocytes with
cerebriform nuclear contours, with smaller versions
referred to as Lutzner cells, and larger ones as classical
Sezary cells.
 Diagnosis of Sezary syndrome requires at least 1,000
such cells per square millimeter with positive clones

41. A mixed population of small
and large tumor lymphocytes
with cerebriform nuclear
morphology are noted (arrow
on typical Sèzary cell).
Eosinophilia (top cell) is also
frequently present in Sezary
Syndrome and may contribute
to the pruritus and atopy.

42.  * Diagnosis is made when there is a clonal rearrangement
of the T-cell receptor (TCR) in the blood (identified by
PCR or southern blot analysis) plus
 *either
 an absolute Sezary cell count of at least 1000 cells/microL
 *or
one of the following two criteria
 1) Increased CD4+ or CD3+ cells with a CD4 to CD8
ratio of 10 or more.
 2) Increased CD4+ cells with an abnormal phenotype
(such as a CD4+ to CD7- ratio ≥40 percent or a
CD4+ to CD26- ratio ≥30 percent)

43. 1)Other causes of erythroderma: atopic dermatitis,
seborrheic dermatitis, pityriasis rubra piliaris, psoriasis
2) Advanced mycosis fungoides
3) Adult T cell lymphoma/leukemia

44.  Spectrum of related, relatively low-grade disorders that
primarily affect skin and develop from an activated or
transformed large T cell that expresses the CD30 antigen.
 CD30 antigen is a cytokine receptor belonging to the
tumor necrosis factor receptor superfamily
 Second most common form of cutaneous T-cell lymphomas
 It includes:
a)primary cutaneous anaplastic large cell lymphoma (cALCL),
 b)lymphomatoid papulosis and
 c)borderline cases

45.  CLINICAL FEATURES – solitary or localised tumours
or nodules, large > 2cm, often ulcerated, red brown
tumours.
 Age- 60 yrs
 M:F- 2-3:1
 Partial regression is common

46. Nodular or diffuse dermal infiltrate
sheets of cohesive CD30+
atypical cells; may also involve
superficial cutis
A non neoplastic mixed
inflammatory infiltrate of small
reactive lymphocytes, macrophages,
eosinophils is present

47. ATYPICAL CELLS- large
rounded or irregular
vesicular nuclei; prominent
centrally placed nucleoli;
ample clear to amphophilic
cytoplasm

48. CD 30 IMMUNOSTAINING : strong
cytoplasmic membrane staining of tumor cells
According to the WHO-
EORTC system, cALCL is
classified by the expression of
CD30 in more than 75% of
large atypical cells
Cells may also be CD4+;
LOSS OF PAN-T MARKERS
(CD2,CD3,CD5) may occur
EMA and ALK are not
expressed in C-ALCL, but
these two markers are positive
in systemic (nodal) anaplastic
large cell lymphoma
(ALCL).

49.  Clonal rearrangement of TCR genes is detected in
90% of cases
 Translocation (t2;5) (p23;q35) charateristic of
systemic ALCL is rarely, if ever, found in primary
cALCL

50.  CLINICAL FEATURES- presence of a
self-healing skin eruption of erythematous
papules and nodules that may become
haemorrhagic, necrotic, and/or ulcerative
 While individual lesions take weeks to
several months to resolve, the disease may
recur for decades and is highly variable
 Patients should be monitored lifelong since
2-25% of patients develop second
lymphoma such as Hodgkin lymphoma or
anaplastic large cell lymphoma

52. Type A lymphomatoid papulosis

53.  Borderline cases- those in which a difference between the
clinical and histologic appearance exists.
 Include cases with the clinical presentation of a
CD30+ CALCL but histologic features suggestive of LyP,
and, conversely, cases with a recurrent, self-healing skin
eruption that shows histologic features characteristic of a
CD30+ CALCL.
 The distinction between LyP and CD30+ CALCL is not
always possible based on histologic criteria.
 LyP type C has been described as a borderline lesion of
CD30+ CALCL.
 Thus, the clinical appearance and the clinical course over
time are used as decisive criteria for the definitive diagnosis
and choice of treatment.

55.  Provisional category in WHO-EORTC clasification
 Characterised by CD8+ cytotoxic epidermotropic T
cell infiltrates
 CLINICAL FEATURES- mean age- 53 yrs
 ulcerated and necrotic eruptive papules, nodules, and
tumors with frequent dissemination to other visceral
sites- lungs,testis,CNS,oral mucosa
 Lymph nodes – typically spared
 Aggressive course. Mean survival – 32 months

56.  MICROSCOPIC FEATURES- Medium to large
pleomorphic cells; pronounced epidermotropism.
 Epidermis often ulcerated + necrotic keratinocytes+
spongiosis
 IMMUNOPHENOTYPICALLY- βF1+, CD3+,
CD8+, granzyme B+, perforin+,TIA-1+ and CD4-.
 MOLECULAR GENETICS-clonal TCR gene
rearrangements are present in most of cases

57.  Provisional category
 Small to medium sized pleomorphic CD4+ CTCL
without a history of classic patches and plaques of MF
and a favorable clinical course
 CLINICAL FEATURES-mean age- 69 yrs
solitary nodule on the face, upper arms, or trunk is
common. Patients may also present with multiple papules
or nodules, but lack patches or plaques.

58.  MICROSCOPIC FEATURES- diffuse growth
pattern in dermis or subcutis; epidermotropism focal
and inconspicous; neoplastic infiltrate is
accompanied by mixed inflammatory infiltrate.
 IMMUNOPHENOTYPICALLY- CD4+ CD8-
Loss of CD2, CD3, CD5. CD30-

59.  Subcutaneous panniculitis-like T-cell lymphoma
(SPTCL) is defined as a rare lymphoma that
(a) primarily infiltrates subcutaneous tissue;
(b) shows high-grade cytologic features;
(c) is composed of T cells with a cytotoxic phenotype
It only consists of cases with α β + T cell phenotype; cases
with γδ T cell phenotype are included in separate category

60.  CLINICAL FEATURES- subcutaneous nodules
 and plaques, usually on the legs or trunk.
 Systemic symptoms and signs, when present, may relate to
hemophagocytic syndrome with pancytopenia, fever, and
hepatosplenomegaly usually in the absence of
lymphadenopathy

61. diffuse, variably cellular infiltrate
involving both septae and lobules
within the subcutis; sparing of
dermis; INFILTRATE- smaller
lymphocytes with visible cytoplasm
admixed with larger transformed cells
with hyperchromatic nuclei
Rimming of individual adipocytes by neoplastic T cells -characteristic,
but not specific, feature

62. CD3+, CD4-, CD8+,CD5+,TIA+,granzyme B +
MOLECULAR GENETICS- clonal TCR rearrangement in 50%
cases
TIA-1 immunohistochemistry showing characteristic
rimming about individual adipocytes.

63.  Provisional category
 CLINICAL FEATURES- eroded to ulcerated patches,
deep tumours located on extremities of adults.
 Constitutional symptoms usually present
 Mucosal and extranodal sites frequently involved
 Bone marrow, lymph nodes, and spleen are spared
 Highly aggressive course

64.  MICROSCOPIC FEATURES-can be predominantly
epidermotropic, dermal, or subcutaneous.
 Subcutaneous infiltrates show rimming of neoplastic
cells around individual adipocytes, similar to
subcutaneous panniculitis–like T-cell lymphoma, but
dermis and/or epidermis also are involved
 IMMUNOPHENOTYPE CD3+, CD56+,
granzymeB+, TIA-1+, CD4 −, CD8−, CD5−, and βF1−
 MOLECULAR GENETICS- Clonal rearrangement of
the TCR-γ gene occurs

65.  Develops in a small minority individuals with prolonged
infection with human T-cell leukemia virus type 1
(HTLV-1)
 MICROSCOPIC FEATURES-a superficial or diffuse
infiltrate of pleomorphic multinucleate T lymphocytes
with prominent epidermotropism is seen.
 Lesion may be indistinguishable from mycosis
fungoides
 IMMUNOPHENOTYPE- CD3+,CD4+,CD8-, CD25+
 MOLECULAR GENETICS- Clonal rearrangement of
the TCR genes and clonal integration of HTLV-1 occur

66.  Rare variant
 Neoplastic cells are NK cell phenotype, can be cytotoxic T cell derived
and are always EBV positive.
 CLINICAL FEATURES-multiple ulcerated plaques and nodules typically
distributed on the trunk or extremities. Accompanying systemic
symptoms are common.
 MICROSCOPIC FEATURES-Medium-sized pleomorphic lymphocytic
infiltrates are present in the dermis and subcutis and show prominent
localization and destruction of blood vessels. Apoptosis and necrosis are
conspicuous.
 IMMUNOPHENOTYPE-CD2+, CD56+, surfaceCD3−, TIA-1+,
granzyme B+, perforin+, and EBV+

68. CUTANEOUS T- cell and NK- cell Lymphomas
1. MYCOSIS FUNGOIDES (MF)
2. MYCOSIS FUNGOIDES VARIANTS AND SUBTYPES:
a) Folliculotropic MF
b) Pagetoid reticulois
c) Granulomatous slack skin
3. SEAZARY SYNDROME
4. ADULT T- cell LYMPHOMA
5. PRIMARY CUTANEOUS CD30+ LYMPHOPROLIFERATIVE DISORDERS
a) Primary cutaneous anaplastic large cell lymphoma (cALCL)
b) Lymphomatoid papulosis
6. SUBCUTANEOUS PANNICULITIS LIKE T CELL LYMPHOMA
7. EXTRANODAL NK/T- cell LYMPHOMA, NASAL TYPE
8. PRIMARY CUTANEOUS PERIPHERAL T- cell LYMPHOMA, UNSPECIFIED
a) Primary Cutaneous Aggressive Epidermotropic CD8+ T- Cell Lymphoma
b) Cutaneous γ/ δ T- Cell Lymphoma
c) Primary Cutaneous CD4+ Small/Medium Sized Pleomorphic T- Cell Lymphoma

69. CUTANEOUS B-cell LYMPHOMAS
1. Primary cutaneous follicle centre lymphoma
2. Primary cutaneous marginal zone B-cell lymphoma
3. Primary cutaneous diffuse large B-cell lymphoma, leg type
4. Primary cutaneous diffuse large B-cell lymphoma , other
5. Intravascular large B-cell lymphoma
PRECURSOR HEMATOLOGIC NEOPLASM
CD4+/CD56+ hematodermic neoplasm (blastic NK cell lymphoma)

72. Neoplasm derived from follicular centre B cells including
centrocytes (cleaved follicular centre cells) and centroblasts
(non cleaved follicular centre cells)
Most common type
CLINICAL FEATURES – middle age men
one to several red- to plum-colored
plaques, nodules or tumours;
Head and neck or upper trunk;

73. cutaneous infiltrates are nodular or diffuse, usually sparing the epidermis.

74. nodules are similar to germinal centers
of lymph nodes; monomorphic
neoplastic cells; devoid of mantle zone;
no tingible body macrophages are
present
Early lesions are mostly centrocytic,
containing cells with small to large
cleaved nuclei, with fewer
centroblastic cells, which are large and
contain prominent nucleoli

75.  IMMUNOPHENOTYPING- CD20, CD79a, bcl-6
CD 20 STAINING BCL-6 STAINING NEGATIVE FOR MUM-1
Weak heterogeneous expression of Bcl-2 CD 21 highlighting FOLLICULAR
DENDRITIC CELLS meshwork

76.  Predominance of centroblasts and immunoblasts.
 CLINICAL FEATURES- usually women of 70 years
 Red to blue nodules on leg
 Has poor prognosis

77. Diffuse dense non epidermotropic monotonous infiltrates of predominantly
medium to large cells with round nuclei, prominent nucleoli and frequent
mitosis resembling centroblasts, large centrocytes, immunoblasts.

78. CD 20 STAINING IRF4/MUM1 STAINING + BCL2 STAINING +
These are in contrast to follicular centre cell
lymphoma of head and neck

79.  Lymphoma of small lymphoplasmacytoid cells, small
lymphocytes, and plasma cells with monotypic
cytoplasmic Ig.
 In 2008 WHO classification, marginal zone lymphomas
of skin are grouped into broader category of extranodal
marginal zone lymphoma of mucosa associated
lymphoid tissues(MALT lymphomas)
 CLINICAL FEATURES- solitary or multiple cutaneous
or subcutaneous tumors on the trunk and extremities

80. nodular or diffuse infiltrates of
small lymphoplasmacytoid
cells, small lymphocytes, and
plasma cells are present that
can be associated with
centrocytes and centroblasts.
Cell of origin – post germinal centre marginal zone B cell

81. Reactive B cells follicles
Neoplastic cells infiltration in
marginal zone distribution

82. Atypical neoplastic cells have irregular
nuclear contours and slightly dispersed
chromatin
Some proliferations are composed of
cells with abundant clear cytoplasm
imparting a monocytoid appearance

83. CD 20+ BCL 2+
NEGATIVE FOR CD5, CD 10 and BCL 6

84.  Intravascular B-cell lymphoma with a relatively poor
survival rate at 5 years, especially if sites other than skin
are involved.
 CLINICAL FEATURES-violet patches and plaques on
the legs and trunk, often thought to be subcutaneous
 MICROSCOPIC FEATURES-dermal and subcutaneous
blood vessels are dilated and stuffed with tumor cells
that are somewhat pleomorphic
 IMMUNOPHENOTYPICALLY-cells are CD20+ and
CD79a+, with monotypic surface Ig

86. Lymphoblastic lymphomas may be of either B or T cell
lineage
Although majority of systemic lymphoblastic lymphomas
are of T cell lineage, but its B cell lineage lymphomas
which show tendency for cutaneous involvement
CLINICAL FEATURES- <35 years
head and neck

87. Nodular or diffuse dermal
infiltrate; mitotically active
lymphoblasts with convoluted
nuclei containing finely
stippled chromatin and
inconspicious nucleoli

88.  Precursor B cell
 Neoplastic cells lack surface immnoglobulin expression
 May harbour cytoplasmic μ chain
 +  TdT, CD79a, CD19, CD 10

 MOLECULAR GENETICS
 Favorable prognosis: hyperdiploidy >50 chromosomes
 Unfavorable prognosis: hypodiploidy, t(9;22), t(4;11)
 t(1;19)

89.  Most common mature B cell neoplasm to secondarily
involve skin- leukaemia cutis
 CLINICAL FEATURES- older adults; M:F- 2:1
 Leukaemia cutis occurs in patients with established
CLL/SLL
 May produce localized or disseminated erythematous
plaques, papules or nodules

90.  May be angiocentric pattern, interstitial pattern and
mixed nodular/diffuse pattern
 Epidermis and papillary dermis uninvolved- typical
grenz zone seen
Diffuse, cellular infiltrate
composed of uniform populations
of small lymphocytes containing
rounded, hyperchromatic nuclei
with inconspicuous nucleoli.

91.  + ve  CD 19, CD5, CD79a, CD23, CD43
 -ve  CD 10 , cyclin D1

92.  Low grade neoplasm of centrocytes and centroblasts
(follicular centre cells)
 CLINICAL FEATURES- >59 years
 head and neck

93. The dermis is replaced by nodules of neoplastic cells that resemble
germinal centers but lack mantle zones.

94.  Cell of origin – germinal B cell
 +  surface immunoglobulin, BCL2 , CD 10, CD 19,
CD 20, CD22
 -ve  CD5 , CD43

 MOLECULAR GENETICS-
t(14;18)

95. B cell neoplasm of uniform populations of small to
medium sized lymphocytes – resemble centrocytes
CLINICAL FEATURES- middle aged to older
 Disease is usually advanced at time of detection (stage III or
IV) and generally affects lymph nodes, spleen, bone marrow
with or without peripheral blood involvement, and
gastrointestinal tract
 Involvement of skin – rare
 Cutaneous MCL more aggressive than PCFCL or
plasmacytoid B-CLL/SLL . Median survival – 3-5 years

96. vaguely nodular to diffuse
infiltrate composed of small- to
medium-sized lymphocytes.

97.  Peripheral B cell of inner mantle zone
CD 20 +
+VE  CD5, CD43, BCL2, Cyclin D1
-ve  CD 10 , CD23
MOLECULAR GENETICS-
t(11;14) involving cyclin D1 gene and
immunoglobulin heavy chain locus

98.  Aggressive lymphoma
 Diffuse tissue infiltration by monotonous populations of
large histiocytoid malignant lymphocytes
 Associated with EBV
 CLINICAL FEATURES- median age 70 years
 occasionally children also affected
 red to purpuric nodules

99. Dermis is diffusely effaced by a
destructive infiltrate causing effacement
of pre-existing structures
Infiltrate is composed of large
neoplastic lymphocytes
resembling centroblasts

100.  Peripheral germinal centre or post germinal centre B
cell
 CD19, CD20, CD22, CD79a

101.  Considered rare subtype of DLBCL
 Intraluminal aggregates of large malignant B cells
within vessels of involved tissues
 CLINICAL FEATURES- adults
 Widely disseminated with involvement of extranodal
tissues including skin  red plaques and nodules

102. Superficial dermal vessels are
partially occluded by hyperchromatic
malignant cells.
malignant-appearing lymphocytes
partially adherent to the endothelial
surface of involved vessels.

103.  Peripheral germinal centre or post germinal centre
origindefective homing receptors CD11a/ CD18
impaired diapedesis  intravascular accumulation
 +ve  CD20, CD5, CD10


107.  Rare aggressive neoplasm
 Once thought to have an NK cell origin, but now it
is believed to be derived from plasmacytoid
dendritic cells.The neoplastic cells characteristically
coexpress CD4 and CD56 without B-, T-, and NK-
cell or myeloid lineage-specific markers
 CLINICAL FEATURES-cutaneous lesions that
typically are solitary or localized nodules or tumors
in elderly men.

108.  dermal infiltrate of monotonous medium-sized cells
with blastoid morphology is present regular nuclear
contours, dispersed chromatin, and small, distinct
nucleoli
 Mitoses are frequent, but angiodestruction and necrosis
are not seen

109. CD 4+ CD 56 + CD 123 +
MPO –ve
Also –ve for CD3, CD33

110. THANK
YOU….