Lymph nodes Flashcards
Name some clinical, morphological, immunohistochemial features, cytogenetics of anaplastic large cell lymphoma?
- 2 subgroups; ALK+ and ALK-
- ALK+ usually presents in young adults, skin/soft tissue, good prognosis
- ALK- usually presents in older individuals, more aggressive, worse prognosis
- Cohesive proliferation of neoplastic T/null cell phenotype, subcapsular in nodal
- Hallmark cells: polylobated wreath like nuclei within large cells with multiple nucleoli
- background of prominent mixed inflammatory cells
- multiple morphologic variants incudling classic/small cell/sarcomatoid etc.
- IHC CD30+, EMA+, CD25+ with variable CD2/3/4/TIA1/granzyme B/perforin
- ALK-1 positive in subset with t (2;5) ALK-NPMN1 but other translocation partners
T-cell lymphoblastic leukemia/lymphoma presents as a mediastinal mass. What is the ddx?
- Thymic lesions: hyperplastic thymus, thymoma, thymic carcinoma
- hodgkin lymphoma
- germ cell tumor
- metastasis
What is the cell of origin of T-cell angioimmunoblatic Tcell lymphoma. What are the clinical and morphologic features of this neoplasm?
- Putative cell of origin: follicular T-cell
- Clinical: fever, weight loss, skin rash, polyclonal hypergammaglobulinemia (can have clonal B-cell changes too)
- autoimmune hemolytic anemia
- increased susceptibility to infections/immunosuppression
- diffuse lymphadenopathy
- morphology: effaced nodal architecture, pleomorphic background of lymphocytes, plasma cells, eos, immunobasts
- sparing of subcapsular sinuses
- prominent vascularity with arborizing vessels
- extrafollicular proliferation of CD21/23 positive follicular dendritic cells
- scattered neoplastic T cells with clear cytoplasm, expressing C3/CD4/BCL6/CXCL13
- 2nd population of CD20+immunoblasts
- Usually EBER+
- cytogenetics: trisomy 3,5,X
*** possible monoclonal rearrangement of both TCR and IGH receptor genes
List 4 types of primary extranodal T/NK neoplasms
- Extranodal NK/T-cell lymphoma, T-cell type
- Enteropathy associated T-cell lymphoma
- Hepatosplenic T-cell lymphoma
- Subcutaneous panniculitis-like T-cell lymphoma
- Primary cutaneous T-cell neoplasms:
Mycosis fungoideds/Sezary syndrome
- Primary cutaneous CD30+ lymphoproliferative disorders
- ALCL (primary cutaneous)
Compare and contrast Classic hodgkins and NLPHL
CHL
morphology: macronodules, fibrou bands, pleomorphic background of lymphos,eos, histiocytes. Mononucleate/binucleate Reed-Sternbergs with conspicuous nuclei.
IHC: CD30/CD15/PAX5/MUM1 POSITIVE. EBER more likely to be positive.
CD20/OCT2/BOB1/CD45 NEGATIVE
IGH/TCR neg
NLPHL:
Morphology: macronodules without fibrosis, more monotonous background of small lymphs. Polylobated LPs with inconspicuous nuclei and wreats of CD57+ lymphs.
IHC: CD45/CD20/PAX5/MUM1, EMA, OCT2, BOB1
CD15/CD30/CD3/EBER NEGATIVE
IGH: may be rearranged
Classify Hodgkins lymphoma
Nodular lymphocyte predominant
Classic
- nodular sclerosing
- lymphocyte rich
- lymphocyte depleted
- mixed cellularity
List 5 factors contributing to renal insufficiency in plasma cell myeloma
- Hypercalcemia
- Hyperuricemia
- Hyperviscosity
- Recurrent bacterial infections/pyelonephritis
- Proteinuria (Bence-Jones light chain nephrotoxicity)
- AL amyloidosis
- Extramedullary plasma cell infiltrates
- Contrast/radiographic studies
What are the diagnostic criteria for symptomatic plasma cell myeloma?
- M protein in serum/urine
- BM clonal plasmacytosis/plasmacytoma
- Organ or tissue impairment (eg. renal function, fever, weight loss etc.)
List 5 distinct clinicopathologic plasma cell disorders
- Plasma cell myeloma (multiple myeloma) including asymptomatic myeloma, non-secretory myeloma, plasma cell leukemia
- Plasmacytoma including solitary plasmacytoma, extraosseus plasmacytoma
- Osteosclerotic myeloma (POEMS-polyneuropathy, organomegally, endocrine disturbance, M protein, skin changes)
- Monoclonal gammopathy of uncertain significance
- Immunoglobulin deposition disease (primary amyloidosis, systmeic light/heavy chain deposition disease)
- Heavy chain diseases: Gamma-HCD, alpha-HCD, Mu0HCD, Waldenstroms macroglobulinemia
B-cell lymphomas: list some translocations/cytogenetic alterations that can be detected by FISH
- Follicular lymphoma t (14;18) BCL2-IGH
- 17p deletions/mutations-p53 gene
- Additional BCL6, MYC gene abberations
- MALT t(11;18) API2/MALT associated with resistance to H.pylori eradication therapy
- Splenic marginal zone (loss of 7q, dysregulation of CDK6 gene)
- Diffuse large B cell (t 14:18, BCL6 or CMYC)
- Burkitt t (8;14), (2;8) or (8:22) fusion genes of C-MYC with IGH etc.
- Mantle cell lymphoma (11;14) Cyclin D1/IGH
How does BCL6 figure into the pathogenesis of DLBCL?
- Acquired aberrations of BCL-6 gene may be compounded by additional cytogenetic abberations (including BCL2, C-MYC)
- Overexpression of BCL-6 protein results in anti-p53 actiity and disruption of DNA repair mcehanisms
- Overexpression of BCL-6 represses factors promoting germinal centre differentiation
- BCL6 locus is on chromosome 3 (DNA binding zinc-finger transcription repressor)
List some subtypes of DLBCL
- Primary mediastinal DLBCL
- Primary effusion lymphoma
- Primary cutaenous DLBCL
- Intravascular DLBCL
- T-cell rich B-cell lymphoma
- Primary CNS DLBCL
- Primary cutaneous DLBCL, leg type
- EBV positive DLBCL of the elderly
- DLBCL from chronic inflammation
- ALK+ DLBCL
- Plasmablastic lymphoma
HHV-8 associated large B-cell lymphoma from multicentric Castleman’s
What are negative prognostic factors in follicular lymphoma?
- presence of diffuse areas of centroblasts (grade 3b)
- Blastic cytomorphology with high ki67
- Additional cytogenetic abnormalities (in addition to t 14;18) including p53 inactivation, activation of C-MYC/BCL-6 genes
- loss of BCL-6 protein and acquisition of MUM-1 expression
List architectural patterns of chronic non-specific lymphadenopathy & clinicopathological associations
- Follicular pattern: RA, SLE, toxoplasmosis, early HIV, also in LN draining any infection
- Sinus pattern: sinus histiocytosis w/massive lymphadenopathy (Rosai-Dorfman), local drainage from malignancies
- Paracortical hyperplasia: dermatopathic lymphadenopathy, infectious mononucleosis, other viral
- Mixed: chronic/late HIV infection
What are important diagnostic features of syphilis lymphadenitis?
Extensive follicular hyperplasia
Lymphoplasmacytic periarteritis
Epithelioid granulomas and rare giant cells
thickened capsule
prominent vessel in interfollicular areas
extensive plasmacytosis in interfollicular areas
Spirochetes (treponema pallidum) can be seen with Warthin Starry Stain
PCR+ for t. pallidum
Compare and contrast reactive follicles with follicular lymphoma
Reactive: variable shapes, located in cortex, preserved interfollicular area, variably sized germinal centers with tingible body macrophages and mitoses, mantle zones sharply demarcated, polarized (dark and light zone). They are BCL2 neg, but positive for CD10, BCL6, CD21/23 highlight intact meshwork and ki67 is elevated. B-cell IGH receptor is polyclonal and BCL2 gene is intact.
FL: fused/crowded germinal centers in all compartments effacing interfollicular area, monomorphic germinal centers lacking tingible body macrophages with only rare mitoses and absent mantle zone. No polarity. IHC: BCL2+, CD10+, BCL6+, distorted meshwork by CD21/23, low ki67. Monoclonal IGH receptor and BCL2 gene rearragnements.
What are the clinicopathologic variants of Castleman’s and what are the salient features?
Both are forms of lymphoid hyperplasia
Hyaline vascular variant (unicentric)
**- **atrophic appearing and lymphocyte depleted germinal centers with hyaline deposits at centre
- mantle cell hyperplasia with concentric layers forming onion-skin lesions
- prominent interfollicular vascularity, with vessels penetrating germinal centers forming lollipop lesions
- lymphocytes mainly CD21/CD23/CD35 folliciular dendritic cells
Plasma cell variant (unicentric, multicentric)
Follicular hyperplasia with large germinal centers
Diffuse plasma cells between follicles, often with Russell bodies
No hyaline-vascular changes present
Center of follicle has amorphic eosinophilic material (fibrin, immune complexes)
HHV8 related, plasmablastic variant
What are the morphologic features diagnostic of progressive transformation of germinal centers?
- Retained nodal architecture with follicular hyperplasia
- Well-demarcated macronodular structures
- Intact interfollicular areas
- Poorly defined mantle zones with progressive fusion and infiltration of germinal centres by IGM/IGD positive mantle zone B cells
- Collectoins of epithelioid histiocytes surrounding PTC macronodules
- Lack of LP cells of NLPHL
What’s emperiopolesis and what are the morphologic features of Rosai-Dorfman?
Emperiopolesis: process of engulfment of viable/intact cells into intracytoplasmic vacuoles by macrophage cells;
Rosai Dorfman: nodla enlargement/extranodal mass
exbuerant expansion of sinuses
Sinuses filled with S100/CD68/CD4 positive histiocytes lacking Cd1a or langerin
Emperiopolesis
Polyclonal plasmacytosis in the medulla
Some association with IgG4
Name 3 clinical conditions that may result in impaired immunodeficiency
- Congenital immunodeficiency disorders (severe combined immunodeficiency, x-linked agammaglobulinemia…)
- Chronic viral infections, HIV/HTLV/HHV8
- Iatrogenic/immunosuppressive therapy: post-BMT/solid organ/malignancy; chemotherapy, steroids, cyclosporine, azathioprine, radiation
- Autoimmune disorders: Sjogren, Hashimoto, UC, Crohns
What 3 patterns of HIV lymphadenitis are there? What does the typical acute pattern show?
Acute, chronic, burned out
acute phase: florid follicular hyperplasia, expanded large and irregularly (dumbbell) shaped germinal centers, attenduated mantle zones giving appearance of naked germinal centeres and follculolysis, aggregates of plasma cells, macrophages, monocytoid B cells, immunoblasts in interfollicular areas with Warthen-Finkeldey multinucleate igiant cells, possible neutrophil infiltration in sinuses
What does acute lymphadentis with EB look like?
Paracortex expapnded by heterogenous population of immunoblasts, centroblasts, plasmablasts
Immunoblastic rxn that can be florid, giving moth-eaten look
Numerous CD30+ immunoblasts
Backround of CD3/CD8+ cytotoxic Ts
EBV+ by EBER (ish) or IHC for EBV LMP1
Positive monospot test
germline configuration of IgG/TCR
What human viruses of the Herpesviridae family, other than EBV, can cause distintive lymph node patterns?
Human herpes virus (HSV1, HSV2) can give herpes lymphadenitis
Varicella herpes zoster (HHV3)
CMV (HHV5) giving CMV lymphadenitis
HHV8, giivng Castleman lymphadenopathy, plasma cell variant
Toxoplasmosis: give 2 clinical and 3 histologic featurs
- Usually solitary cervical lymphadenopathy, often young women
- Protozoan Toxoplasma gondii (from cat shit)
- HISTO: background of follicular hyperplasia, collections of epithelioid histiocytes encroaching on reactive germinal centres, monocytoid B-cell hyperplasia in subcapsular/trabecular sinuses
Dermatopathic lymphadenitis. What are morphological and IHC features of this specific lymph node reaction pattern?
Common in lymph nodes draining areas of cutaenous inflammation/underlying skin disease
Macronodules in paracortical T-zone
Mottled appearance, with pleomorphic infiltrate of:
- S100 dendritic cells CD1a+ Langerhans cels, C68+ hemosiderophages/ or melanophages
What are some common symptoms affecting pts with Kikuchi lymphadenitis?
Cervical lymphadenopathy, fever, leukopenia, skin rash
What is the morphologic ddx of syphilis related lymphadenitis?
Tuberculous lymphadenitis
Rheumatoid arthritic lymphadenitis
Polyarteritis nodosa
Sarcoidosis
Follicular lymphoma
IgG4
List some clinical features associated with multicentric plasma cell variant of Castlemans
B symptoms (fever, weight loss, night sweats), hepatosplenomegally, cytopenias, polyclonal hypergammaglobulinemia, increased LDH, ESR, CRP, IL-6, increased susceptibility to infections, association with POEMS, association with HIV, HHV8
Rheumatoid arthritis may be associated with which clinical findings?
- cytopenias, monoclonal paraprotein, amyloid, increased risk of B-cell neoplasm (de novo or therapy induced), splenomegally, clonal proliferation of T-NK cells, lymphadenoapthy
What are some morphologic features of rheumatoid arthritis related lymphadenopathy?
- extensive follicular hyperplasia of cortex/medulla
Prominent germinal centers
intense interfollicular plasmacytosis, some russell bodies
Distended sinuses filled with neutorphils
small areas of necrosis
What are some pathogenic factors associated with Castleman’s?
- HHV8, HIV
- IL-6/VEGF overexpression