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Lymphoproliferative and myeloproliferative disorders Flashcards

1
Q

Jessner’s epidemiology

A
  • middle aged adults

- no gender predilection

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2
Q

Jessner’s pathogenesis

A
  • Controversial entity: some believe it is a variant of lupus or PMLE, versus pseudolymphoma
  • Co-occurrences with: lupus, PMLE, Lyme disease
  • Rarely: drug induced: ACEI, glatiramer acetat
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3
Q

Jessner’s Clinical

A
  • Distribution: head, neck, upper back (think acne)
  • Asymptomatic erythematous papules, plaques and nodules. Can have annular plaques with central clearing
  • No epidermal change
  • Last several weeks to months
  • No systemic involvement
  • Spontaneous resolution occurs, but can recur
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4
Q

Jessner’s Histology

A
  • Grenz zone
  • No, or very sparse, interface dermatitis
  • Superficial and deep peri-vascular lymphocytic infiltrate that may be peri-appendageal
  • Mildly increased mucin
  • Immunohistochemistry:
    • Mixed T-cell infiltrate with a predominance of CD8 lymphocytes
    • Mixed with CD123 plasmacytoid denritic cells
    • Distribution of the dendritic cells is identical to what is seen in LE tumidus
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5
Q

Jessner’s ddx

A
  • Infectious: borderline lepromatous leprosy
  • Immune: PMLE, lupus tumidus, granuloma faciale
  • Infiltrates: pseudolymphoma, REM
  • Neoplastic: cutaneous lymphoma
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6
Q

Jessner’s treatment

A
  • PAGED:
    • education: can resolve spontaneously within months to years, without scarring
  • TOPICAL
    • Topical steroids and calcineurin inhibitors
    • Oral systemic:
      • 50% improvement with plaquenil
      • 76% improvement with thalidomide compared to 16% placebo (crossover study)
    • Procedural:
      • excision
      • resistant to radiation therapy,
      • cases of PDL and chemo and PDT
      • Caution light as ??lupus/PMLE ddx
    • Intra-lesional steroids –> limited success
    • Camouflage and cosmetic
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7
Q

Pseudolymphoma epidemiology

A

Children and adults

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8
Q

Pseudolymphoma pathogenesis

A
  • Exaggerated local immunologic reaction to stimulus (often underrecognised)
  • Hapten driven immunologic response –> cells damaged by toxic effect of stimuli
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9
Q

Pseudolymphoma causative agents

A
  • Anything that externally compromises the skin barrier
    • Arthropod bites
    • Tattoos
    • Vaccinations
  • Contact allergens
    • Contact allergens
    • Metal implants
  • Infections
    • Lyme disease
    • Herpes Zoster
  • Medications - has a crossover with DRESS drugs. You can have DRESS patients who have atypical lymphocytes in the blood and skin
    • Anti-convulstants
    • Anti-arrhythmics
    • Antibiotics
    • Antidepressants
    • Anti-histamines
    • Antihypertensives
    • Anti-psychotics
    • Chemotherapy
    • Lipid lowering drugs
    • NSAIDs
    • Allopurinol, dapsone, etc
    • Benzos
    • Steroid hormones
  • Can also be unknown!
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10
Q

Pseudolymphoma clinical

A
  • Single, firm 1-3 cm erythematous to violaceous plaque or nodule
  • Head, neck or upper extremities
  • Can be multiple, clustered papules
  • Can be large panniculitis like nodules
  • Lacks scale
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11
Q

B cell Pseudolymphoma histology

A
  • Superficial and deep nodular or diffuse infiltrate of lymphocytes
  • Admixed histiocytes, and occasional plasma cells and eosinophils
  • When florid: germinal centres with prominent tingible body macrophages
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12
Q

T cell Pseudolymphoma histology

A
  • CD4 T helper lymphocytes are commonly observed within the dermis, admixed with a minority of CD8 cytotoxic/suppressor T cells
  • Drug induced - may have an MF-like pattern
  • May see: epidermotropism, spongiosis, vacuolar degeneration, papillary dermal oedema, red cell extravasation
  • There is no prominent papillary dermal fibrosis (which you see in MF), but T cell clonality may be present
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13
Q

B cell Pseudolymphoma immunohistochemistry and clonality analysis

A

Immunohistochemistry
- Distinct B and T cell compartments
- CD35 or CD21 visualize networks of follicular dendritic cells within reactive germinal centres
- Germinal centre cells have a normal CD20, CD10, BCL6, BCL2
- High proliferative rate: MIB-1
Clonality analysis
- Clonality of IgH gene rearrangement or restricted kappa or delta expression is not seen in pseudolymphoma
- Detection of monoclonal expression of immunoglobulin light chains kappa or delta is a key diagnostic feature for primary cutaneous marginal zone B cell lymphoma. Monoclonaltiy is >10:1 ratio

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14
Q

How is Pseudolymphoma different to follicle centre B cell lymphoma?

A
  • It has a mixed cellular infiltrate such as eosinophils and plasma cells. B cell lymphoma is predominantly lymphocyte
  • It has a reactive germinal centre with a mantle zone and tingible body macrophages present
  • It has polarization of follicles with light and dark areas. B cell lymphoma has monomorphous appearance of follicles without polarization
  • Immunophenotypically it has:
    • T and B lymphocytes. B cell has CD20 B lymphocytes
    • Bcl-6 cells are restricted to lymph follicles. in B cell lymphoma the Bcl-6 cells are outside of lymph follicles
    • Bcl-2 are only on T lymphocytes.
    • High proliferation of germinal centres
    • Mixed kappa and delta expression (restricted in B cell lymphoma)
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15
Q

CD30 Pseudolymphoma histology

A
  • persistent arthropod bite reactions, drug reactions, atypical lymphoid infiltrates associated with cutaneous poxvirus infections.
  • Has polyclonal arrangement of TCR
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16
Q

Pseudolymphoma ddx

A 
External:
Trauma: arthropod bites, tattoo reaction
Infective: Lyme disease, Syphilis
Drug: eruptions
Internal:
Papulosquamous: lichen sclerosus, PLEVA, PPD, contact dermatitis
Immune: lupus
Infiltrates: pseulymphomatous folliculitis
  • Neoplastic:
    • Primary cutaneous marginal zone lymphoma
      • some argue that these are on the same spectrum
      • PCMZL has plasma cells at the periphery of lymphocyte infiltrate
      • Demonstration of monotypic palsma cells with either kappa or lambda light chains distinguishes PCMZL
    • Primary cutaneous follicle centre lymphoma
      • Presence of eosinophils favours pseudolymphoma
    • Secondary cutaneous follicular lymphoma

Rare: APACHE, IgG4, plasmacytosis, hydroa vaccinforme, Kikuchi Fujimoto

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17
Q

What is a tingible body macrophage

A
  • Type of macrophage in germinal centres that contains phagocytosed, apoptotic cells which are degrading
  • Tingible means: staining
  • May play a role in downregulating germinal centre reaction .–> released prostaglandins, and hence a reduced B-cell induction of IL-2
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18
Q

APACHE

A
  • Acral pseudolymphomatous angiokeratoma of children
    • Favours the extremities of children between 2-16 years
    • Unilateral grouping of small, red-violet angiomatous papules
    • Histologically: dermal infiltrates of lymphocytes, histiocytes and plasma cells with prominently thickened capillaries
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19
Q

Kikuchi-Fujimoto: histiocytic necroziting lymphadenitis

A
  • Idiopathic systemic inflammatory disease
  • Young adult women
  • Associations: viral (EBV, CMV), bacterial and autoimmune
  • Systemic: fevers, weight loss, GIT symptoms, cervical lymphadenopathy
  • Cutaneous: 40% of patients –> acneiform eruptions, urticaria, ulcers, indurated erythematous plaques
  • Histo:
    • Of skin: dense superficial and deep perivascular lymphohistiocytic infiltrates with nuclear debris (without neutrophils) and interface change
  • Histology of nodes: necrosis and histiocytic infiltration of the paracortical areas of involved lymph nodes (without identifiable pathogen)
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20
Q

Pseudolymphomatous folliculitis

A
  • Solitary facial nodule
  • Peri-follicular and peri-adnexal dermal infiltrate
  • Infiltrate is mixed, with T or B dominating. There may be cellular atypia and granulomas
  • Irregular hyperplasia and distortion of the follicular epithelium
  • Blurring of DEJ, CD1a/S100 mononuclear cells surround and infiltrate these distorted follicles
  • Needs to be distinguished from CD4 T cell lymphoproliferative disorder (has more pleomorphism, and has PD1 expresion)
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21
Q

Cutaneous and systemic plasmacytosis

A
  • Benign condition
  • Aetiology unknown - ?reactive dysfunction of plasma cells triggered by various stimuli
  • Similar to Castlemans: elevated IL-6 in blood and tissue, but no HHV-8 infection
  • Seen in Asians (particularly Japanese)
  • Multiple reddish-brown, infiltrated maculopapules and plaues
  • Distribution: commonly the trunk
  • Systemic: lymphadenopathy, hepatosplenomegaly, interstitial penumonia, mesangial proliferative GN
  • +/- anaemia, B symptoms, hypergammaglobulinaemia
  • Histology: dense superficial and deep peri-vascualr infiltrates of mature polyclonal plasma cells
    • To demonstrate polyclonality: kappa and lambda immunohistochemistry or FISH
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22
Q

Pseudolymphoma treatment

A
  • Benign –> treat conservatively
  • May resolve without scarring
  • Persistent lesions:
    • Topical steroids
    • Oral systemic: thalidomide for recalcitrant, or treat Lyme disease
    • Procedural:
      • simple excision
      • cryosurgery
      • laser ablation
      • radiation therapy
      • Biopsy –> can stimulate regression
    • Intra-lesional steroids
  • Camouflage
  • Monitor
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23
Q

Extramedullary Haematopoiesis epidemiology

A
  • Neonates

- Can occur in adults with myelofibrosis and less often myelodysplasia or after a splenectomy

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24
Q

Extramedullary Haematopoiesis pathogenesis

A
  • Reflects bone marrow dysfunction
  • Occurs during early embryogenesis and usually stops prior to birth
  • After that, it can occur as a secondary phenomenon when the bone marrow function is altered
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25
Q

Extramedullary Haematopoiesis clinical

A
  • Erythematous to violaceous papules and nodules, that may ulcerate
  • Blueberry muffin baby: widely disseminated. Can be seen in associated with congenital viral infections and prenatal anaemias
  • Dermal haematopoiesis is most commonly seen with:
    • Rubella
    • CMV
  • Associated cutaneous neoplasms: PPHIS
    • Pilomatricoma
    • Pyogenic granuloma
    • Haemangioma
    • Sebaceous naevus
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26
Q

Blueberry muffin baby syndrome Ddx

A
  • External
    • Infections:
      • Pre-natal
      • TORCH
      • Coxsackie
      • Parvovirus
  • Internal
    • Neoplastic
      • Myelodysplasias
      • Congenital Leukaemia
      • Congenital alveolar rhabdomyosarcoma
      • Congenital LCH
      • Neonatal neuroblastoma
      • Congenital leukaemia cutis
      • Vascular
        • Haemangiomatosis
        • Glomuvenous
        • Multifocal lymphangioendothleiomatosis
        • Disseminated extramedullary haematopoiesis
    • Metabolic
      • Anaemias: pre-natal, haemolytic, twin-twin transfusion
      • Haemorrhage
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27
Q

Extramedullary Haematopoiesis histology

A
  • Dermal infiltrate of immature red and white blood cell precursors and megakaryocytes, centred around vessels of the superficial vascular plexus
  • Can extend into the deeper reticular dermis and exhibit a diffuse pattern
  • All three haematopoietiic cell lines are present in varying ratios: erythrocytes, leukocytes, megakaryocytes
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28
Q

Extramedullary Haematopoiesis ddx

A
  • limited histologically
  • Distinguishing it from congenital leukaemia cutis and neonatal neuroblastoma is important –> leukaemia cutis has just leukocytes and not the others
  • Patients with overwhelming marrow involvement from leukaemia may have both EMH and leukaemic involvement of the skin which may make things confusion
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29
Q

Extramedullary haematopoiesis treatment

A
  • treat the underlying BM dysfunction

- if viral, can have spontaneous resolution

30
Q

Leukaemia cutis epidemiology

A
  • ALL –> kids
  • AML and CML –> adults
  • CLL and hairy cell leukaemia –> elderly
  • When see with CML –> can be blast transformation
  • When see with myelodysplatic syndrome –> transformation to AML
31
Q

Leukaemia cutis pathogenesis

A
  • CML:
    • Philadelphia chromosome: translocation between chromosomes 9 and 22 –> results in fusion of BCR and ABL –> activation of tyrosine kinase activity of the fusion oncoprotein. This is targeted by imatinib
  • Promyelocytic leukaemia –> T(15;17) translocation which leads to abnormal expression of a fusion retinoic acid receptor that is the target of all-trans retinoic acid therapy
  • Non-random chromosomal abnormalities exists in ALL and AML that can influence prognosis
  • Mutations can be favourable and unfavourable
    • CLL:
      • 13q deletion is good
      • Trisomy 12 is unsure
      • Deletions of 6q, 11q and 17 p are bad
32
Q

Leukaemia cutis: non-specific reactive skin lesions and what are they most commonly seen with

A
  • Neutrophilic dermatoses
    • Sweets - AML>CML, hairy cell leukaemia
    • Pyoderma gangrenosum - AML, CML, hairy cell leukaemia >ALL, CLL
    • Neutrophilic eccrine hidradenitis - AML the most
  • Reactive erythemas
    • Exaggerated arthropod reactions and erythroderma - CLL
    • Facial erythema and oedema - T cell prolymphocytic leukameia
  • Vasculitis
    • PAN - hairy cell leukamia, CMML
    • Vasculitis - hairy cell, CLL > AMML, AML
    • EED - hairy cell leukaemia, CLL
  • Panniculitis
    • EN - AML, CML, CMML
    • Other panniculitides - hairy cell, AML, CMML
  • Other
    • CLL:
      • urticaria
      • erythema multiforme
      • paraneoplastic pemphigus
      • adult onset eczema (recalcitrant)
    • Acral ischaemia with lividity - CML
    • Granulomatous reactions: MDS
    • Pernio: CMML
33
Q

Leukaemia cutis specific infiltrates

A
  • Firm papules and nodules that often become haemorrhagic
    • Thrombocytopaenia usually plays a role in the bleeding
    • Rarely bullous and ulcerative
    • Distribution: head, neck, trunk, but anywhere, and also arise at sites of trauma or scars
    • Myelogenous leukaemias may present with dermal nodules: chloromas, granulocytic sarcomas, extramedullar myeloid tumours
      • Granulocytic sarcomas may precede the development of systemic leukaemia
      • Gingival hyerplasia, secondary to leukaemic infiltrates, favours acute monocytic or acute myelomonocytic leukaemia
  • Very rarely, skin involvement precedes the leukaemia diagnosis
  • Rarely, leukaemia cutis predates BM involvement by months or even years
34
Q

Chloroma

A
  • Arise in myeloid leukaemia or granulocytic sarcoma
  • Can present as solitary or numerous nodules
  • Appear blue-green –> due to myeloperoxidase granules in the malignant leukocytes
  • May precede development of systemic leukaemia by several months
35
Q

ALL overview

A
  • <6 years of age
  • Head and neck
  • Aggressive
  • Predominantly B-cell ALL
  • Rarely get cutaneous involvement
  • Large, non-ulcerated tumours, nonspecific papulonodules
36
Q

CLL overview

A
  • 70s or older
  • Generalised, may appear at sites of infection
  • Indolent course
  • B cell type
  • Relatively common cutaneous involvement
  • Non-specific papulonodules
37
Q

AML overview

A
  • 70s
  • Generalised distribution, aggressive
  • Most commonly AMML, AMoL
  • Cutaneous invovlement uncommon, nonspecific papulonodules
  • Early presentation
38
Q

CML overview

A
  • most commonly after 50 years of age
  • Most commonly CMML
  • Cutaneous involvement rare, but associated with blast transformation
  • Nonspecific papulonodules
39
Q

AML histology

A
  • neoplastic proliferation of immature myeloid cells
  • Cytoplasmic granules
  • Stain: chloroacetate esterase –> helpful in detecting myeloid differentiation, but when very early may not have granules
  • Most common forms in skin are de novo
  • Stains: myeloperoxidase, CD13, CD33 and CD68
40
Q

ALL histology

A
  • Clonal expansion of immature lymphocytes, more commonly B cell
  • Rarely, cytoplasmic granularity
  • Stain: terminal deoxytransferase
41
Q

CML histology

A
  • Demonstrates a range of myeloid precursors - promyelocytes, metamyelocytes, bands, mature neutrophils
  • Cutaneous is rare, but associated with blast transformation
42
Q

CLL histology

A
  • Dense infiltrate of uniform appearing, small, round lymphocytes of B-cell lineage
  • cells appear mature, but monomorphous nature and paucity of other cell types suggest leukaemic infiltrate
  • peri-adnexal and vascular
  • Stain: CD5, CD20, CD43
43
Q

Leukaemia cutis ddx

A
  • Lymphoma cutis
  • Infectious emboli
  • Vasculitis
  • Drug eruptions
  • Myeloid leukaemias
    • EMH
    • Sweets –> composed mostly of immature cells of meyloid lineage so can be misinterpreted
    • Small vessel vasculitis
    • Neutrophilic dermatoses
44
Q

Cutaneous Hodgkin Lymphoma epi

A
  • utaneous involvement is rare –> 0.5% with HL develop cutaneous involvement
  • Occurs in advanced disease
  • Sign of poor prognosis
  • HL peaks in early adulthood, with second, smaller peak in sixth decade
  • MF and LyP have higher rates of occurrence now
45
Q

Cutaneous Hodgkin Lymphoma pathogenesis

A
  • 30-40% with classic HL have EBV DNA within the Reed-Sternberg cells
  • Role of EBV is not known
  • Reed-Sternberg cells represent the malignant population, and are usually derived from B-cell lymphocytes
46
Q

Cutaneous Hodgkin Lymphoma clinical

A
  • Classic HL includes:
    • Nodular sclerosing (most common)
    • Mixed cellularity
    • Lymphocyte-depleted
  • Non-classic: more indolent –> nodular lymphocyte-predominant HL
  • Cutaneous involvement:
    • Multiple papulonodules or plaques
    • Trunk most common
    • Lesions often distal to affected lymph nodes
  • Extra-cutaneous:
    • Lymphadenopathy
    • Splenomegaly
    • Constitutional symptoms
    • 20-50% paraneoplastic cutaneous disorders: primary pruritis, acquired ichthyosis, persistent dermatitis, hyperpigmentation, EN
47
Q

Cutaneous Hodgkin Lymphoma histology

A
  • Nodular or diffuse dermal infiltrate: lymphocytes, eosinophils, plasma cells
  • No epidermotropism
  • Reed-Sternberg cells and lacunar cells may be present
  • Lacunar cells: large cells with abundant eosinophilic cytoplasm. Retraction fo cytoplasm from adjacent cells during fixation results in a giant cell residing within a clear space
  • Dermal sclerosis may be seen –> extension into S/C fat is common
48
Q

Cutaneous Hodgkin Lymphoma immunohistochemistry

A
  • R-S cells express: CD30 (Ki-1), fascin, CD15, PAX-5, MUM-1, negative for CD45RB and CD20.
  • B/G of lymphocytes predominantly T cells
  • In lymphocyte predominant HL, the malignant cells are positive for CD20
49
Q

Cutaneous Hodgkin Lymphoma ddx - important ones

A
  • cALCL –> stains positive for CD30. Negative for CD15 and PAX-5
    • LyP –> don’t have systemic involvement. Negative for CD15 and PAX-5
50
Q

Cutaneous Hodgkin Lymphoma treatment

A
  • Stage 4: cure rate of 60-70% following combination chemotherapy
  • Recurrent disease: salvage chemo, autologious HSCT, anti-CD30 (brentuximab) and anti-PD1 antibodies
51
Q

Blastic Plasmacytoid Dendritic Cell Neoplasm epidemiology

A
  • extremely rare
  • is a distinct entity
  • grouped with AML-related precursor neoplasms
  • Disease of adults, >50 years
  • M>F 3:1
52
Q

Blastic Plasmacytoid Dendritic Cell Neoplasm pathogenesis

A
  • Malignant proliferation of plasmacytoid dendritic cells
  • These cells produce large amounts of type 1 inferferons: interferon alpha in particular, and TLR –> making them critical in defense against viruses and other pathogens
53
Q

Blastic Plasmacytoid Dendritic Cell Neoplasm clinical

A
  • Solitary or multiple
  • Non-tender, occasionally pruritic
  • Erythematous-violaceous papules, nodules, plaques that can look like bruises
  • Ulceration is common
  • Skin is often the presenting site of involvement
  • Evaluation: regional lymph nodes, peripheral blood, bone marrow involvement
  • Those with initial negative staging eventually develop blood invovlement
  • Constitutional: fevers, chills, night sweats, weight loss –> uncommon but do occur as the disease progresses
  • Isolated reports of developing AML
54
Q

Blastic Plasmacytoid Dendritic Cell Neoplasm histology

A
  • Grenz zone
  • Diffuse dermal infiltrate of monotonous, atypical, medium-sized mononuclear cells
  • Cells: fine blastic chromatin, indistinct nucleoli, scant agranular eosinophilic cytoplasm
  • Intra-tumoral haemorrhage is common
  • Early lesions: infiltrate may be peri-vascular and peri-adnexal
55
Q

Blastic Plasmacytoid Dendritic Cell Neoplasm immunohistochemistry

A
  • Positive: CD4, CD56, CD123 (presence of plasmacytoid dendritic cells - PDC, its easy as 123), TCL1, BDCA2, CD303
    • Negative: myeloperoxidase and EBV
  • Tumour cells have germline configurations of Ig(H&L) and TCR (i.e. lack rearrangement)
56
Q

Blastic Plasmacytoid Dendritic Cell Neoplasm genetics

A
  • CDKN1B - 12p13
  • RB1 - 13q13
  • CDKN2A - 9p21
  • These genes can also be altered in NHL, ALL and hairy cell leukaemia
57
Q

Blastic Plasmacytoid Dendritic Cell Neoplasm ddx

A
  • Neoplastic:
    • AML
    • Other cutaneous lymphomas
  • BPDCN lacks IgH and TCR gene rearrangement, and has a really characteristic immunohistochemical profile
  • Expression of TCL1, BDCA2 and CD2AP diagnoses it
58
Q

Blastic Plasmacytoid Dendritic Cell Neoplasm Rx

A
  • Multidrug chemotherapy –> response rates are high (up to 80%) but relapses rare common –> 1 year median overall survival
  • Allogeneic HSCT
  • Needs aggressive treatment
  • Aberrant activation of NF-kB pathway may represent a therapeutic target
59
Q

Angioimmunoblastic T-cell lymphoma - AITCL epidemiology

A
  • Very rare
  • Midle-aged and elderly
  • M=F
60
Q

Angioimmunoblastic T-cell lymphoma - AITCL pathogenesis

A
  • Considered a mature T-cell neoplasm whose cells of origin are follicular T helper cells
  • Frequent progression to aggressive lymphoma, has clonal rearrangement of TCR
61
Q

Angioimmunoblastic T-cell lymphoma - AITCL clinical

A
  • Usually preset at advanced stage: fever, weight loss, night sweats, generalized lymphadenopathy, hepatosplenomegaly
  • 1/2 cutaneous:
    • Widespread morbilliform that looks like a viral exanthem
    • Petechiae
    • Urticaria
    • Purpura
    • Papulonodules
    • Rarely erythroderma
    • Generalised pruritis
  • Aggressive: median survival < 3 years
62
Q

Angioimmunoblastic T-cell lymphoma - AITCL histology patterns

A
  1. Superficial perivascular infiltrate of eosinophils and lymphocytes (most common) that lack atypia
  2. Sparse perivascular infiltrate with atypical lymphocytes
  3. Denser superficial and deep infiltrate of pleomorphic lymphocytes
  4. Vasculitis (+/- atypical lymphocytes)
  5. Necrotizing granulomas
  • Skin may have increased numbers of venules with a prominent endothelial lining
63
Q

Angioimmunoblastic T-cell lymphoma - AITCL immunohistochemistry and gene mutation

A
  • Corresponds to follicular T helper cells: CD3+, CD4+, CD8-, CD10+, PD-1+, ICOS+, Bcl-6+, CXCL13+
  • EBV negative
  • Molecular analysis: monoclonal TCR rearrangement and polyclonal immunoglobulin pattern
  • Genee mutation: TET2 –> protein product is tet methylcytosine dioxygenase 2 –> involved in DNA methylation, and is implicated in T cell lymphoma
64
Q

Angioimmunoblastic T-cell lymphoma - AITCL ddx

A
  • drug eruption
  • viral exanthem
  • Histo changes are subtle
65
Q

Angioimmunoblastic T-cell lymphoma - AITCL rx

A
  • Majority present with Stage 3-4
  • Prospective RCT: no observable differences among varying regimens, even with HSCT
  • 46% response with induction, but 5 year survival is 33% and 7 year is 29%
66
Q

Lymphomatoid Granulomatosis epidemiology

A
  • Rare
  • 50s-60s
  • M>F 2:1
  • Can affect children, in immunodeficiency syndromes
67
Q

Lymphomatoid Granulomatosis pathogenesis

A
  • EBV (+/- immunosuppression)

- Immunosuppressive factors: renal transplant, Wiscott Aldrich, HIV, X-linked lymphoproliferative syndrome

68
Q

Lymphomatoid Granulomatosis clinical

A
  • Pulmonary: cough, dyspnoea, hcest pain
  • Constitutional: fever, weight loss, malaise, arthralgias, myalgias
  • Cutaneous
    • 25-50% of aptients
    • Nodules or ulcerated plaques
    • Maculopapular exanthem
  • Can affect kidney, brain, GIT, rarely LN and spleen
69
Q

Lymphomatoid Granulomatosis histology grades

A

Three Grades:

  1. Grade 1: polymorphous lymphoid infiltrate without cytologic atypia, a few large cells, a few EBV positive cells (EBER-1)
  2. Grade 2: polymorphous inflammatory background with scattered large cells and numerous EBV positive cells (EBER-1)
  3. Grade 3: Large sheets of B cells and numerous EBER-1 cells over an inflammatory background
    - amount of necrosis increases with grade and angiocentricity/angiodestruction
    - Granulomatous change
70
Q

Lymphomatoid Granulomatosis stains

A
  • CD20
    • CD79a
    • Some cases: monoclonal rearrangement of Jh gene
71
Q

Lymphomatoid Granulomatosis ddx

A
  • Neoplastic
    • Cutaneous lymphoma
  • Infectious
    • Granulomatous
  • Immune
    • Medium vessel vasculitis
  • Infiltrates
    • Pyoderma gangrenosum
    • Granulomatous - Wegeners, sarcoid
72
Q

Lymphomatoid Granulomatosis rx

A
  • Aggressive course - 5 year mortality ranges from 60-90%
  • Higher grade disease - treatment commonly involves multidrug chemotherapy and/or rituximab
  • Grade 1 disease - interferon alpha
  • Reversal of exogenous immunosuppression will also lead to improvement

Derm (57 decks)

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