| Syn:
SKIN PSEUDOLYMPHOMAS / BENIGN LYMPHOID HYPERPLASIA SIMULATING CUTANEOUS LYMPHOMA :
Heterogenous group of lymphoid
infiltrate which may be histologically similar to malignant lympoma . The
clinical presentation and biological outcome of these lesions are
different from lymphoma.
In benign lymphoproliferation there is no evidence of systemic spread for
5 years after the initial skin biopsy.
Visit:
PRIMARY CUTANEOUS LYMPHOMA
Lymphomatoid papulosis
regarded as a pseudo-malignant lesion in the past is now regarded as a
low grade lymphoma.
Cutaneous lymphoid hyperplasia mimicking lymphoma is divided into two main
types depending on the cell type and pattern of cellular infiltrate:
1. B- cell type (usually nodular or diffuse
pattern)
2. T- cell type (usually superficial band like infiltrate in the
superficial dermis, however nodular pattern of dermal infiltrate may be
present.
External Image Links:
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B- cell
lymphoid hyperplasia mimicking B-cell lymphoma:
Synonyms: Lymphocytoma cutis,
B-cell pseudolymphoma, lymphadenosis benigna cutis, Spiegler-Fendt
sarcoid.
Cause: 1) Mostly idiopathic 2) Induced by various stimuli
Stimuli include: Borrelia burgdorferi infection
(Borrelia
burgdorferi-associated lymphocytoma cutis: clinicopathologic,
immunophenotypic, and molecular study of 106 cases.Cutan
Pathol. 2004 Mar;31(3):232-40.)
,
other arthropod bite, ingestion of drugs (phenytoin sodium), tatoo
pigment, allergen injection for hyposensitization, gold injection or
contact with gold earrings, cutaneous vaccination.
Note: B- cell predominant lymphoid hyperplasia is also noted in
Angiolymphoid hyperplasia,
Kimura's disease
and Castleman's disease.
Gross:
- May be solitary and localized or multiple and widespread.
- 3mm to more than 5 cm in diameter.
- Reddish brown papule or nodule.
- Usually located on the head and neck, trunk or on the upper
extremities.
Microscopic features:
Image
The histological features are varied ; The apperances overlap with
those of cutaneous follicle cell
lymphoma and marginal zone B-cell lymphoma of MALT type. ; Dense iniltrate which may be nodular or diffuse in nature ; Inflammatory
infiltrate often noted around dermal appendages and blood vessels ; "Top heavy"
infiltrate (inflammatory infiltrate in the upper dermis) is more common
than "bottom heavy " infiltrate ; Epidermis is spared ; Infiltrate
may extend to the subcutis ; Eosinophils, histiocytes and plasma cells may
be present ; In a few cases lymphoid follicle with well formed mantles
are present separated by small T-cell lymphocytes and scattered T and B immunoblasts ; There may be proliferation of small blood vessels.
T- cell lymphoid
hyperplasia mimicking B-cell lymphoma:
Atypical lymphoid
infiltrates (T-cell pattern) :
- Idiopathic
- Lymphomatoid drug reaction
- Lymphomatoid contact dermatitis
- Viral infection including molluscum contagiosum & herpes simplex.
Image(Atypical
lymphoid cells are present in a patient with herpes simplex infection. The
atypical cells are CD30 positive)
- Arthropod bite reaction (scabies)
- Lymphoproliferative lesion related to EBV
- CD8 positive T cell infiltrate in HIV/AIDS
- Actinic reticuloid
| Lymphomatoid drug
reaction:
- Related to intake of
drugs (carbamazepine, cyclosporin, phenytoin sodium, griseofulvin etc)
- Lesions usually regress after withdrawal of drugs.
- Microscopic features:
Lymphocytic infiltrate in the dermis ; Consists of mostly T cells ;
May be band- like ; Atypical lymphoid cells are present ; There is a
prominent histiocytic component.
- Large CD30 positive T cells are present.
- T- cells are CD4 positive.
- D/D : Mycosis fungoides
|
| Jessner's Lymphocytic
Infiltrate:
Clinically presents as
erythematous plaques in the head and neck region and upper part of trunk.
Etiology is unknown.
Microscopic features: There is a dense perivascular infiltrate (superficial and
deep vessels) and infiltrate around pilo-sebaceous units. Predominantly
T-cells are present together with scattered B-cells.
D/D- Lupus Erythematosus
|
CD8 positive T cells in
AIDS:
Cutaneous
lesions related to AIDS
Presents as plaques or nodules on the face and extremities.
Microscopic features: The lymphoid cellular infiltrate together with some larger
atypical cells in the upper and mid dermis . Eosinophils are also present.
Pautrier's microabscess formation in some cases and mild epidermotropism.
Other changes include lichenoid reaction with vacuolar degeneration &
presence of apoptotic bodies.
The infiltrate consists of T- cells (CD2 , CD3 , CD5 and CD8 positive). |
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