DDx

Question 1

DDx for AML with Dysplasia

Answer 1

1. AML t(6;9)
2. MECOM
3. AML-MR

Question 2

DDx for AML with Monocytoid appearance (M4/M5)

Answer 2

1. NPM1
2. KMT2A (adults)
3. APL (microgranular)
4. NUP98

Question 3

DDx for AML with M7 fts

Answer 3

1. t(1;22)
2. NUP98
3. MECOM
4. KMT2A (kids)
5. CBFa1::GLIS (RAM IMPT)

Question 4

DDx for Basophilia

Answer 4

1. Acute basophilic leukaemia
2. t(6;9)
3. AML t(9;22)
4. CML-BP
5. Mast cell leukaemia

Question 5

Differential diagnosis of Eosinophilia (9)

Answer 5

1. Reactive (Drugs, Allergy/Infection, Solid tumour/LPD)
2. M/L with TK mutation
3. CML
4. AML inv16
5. Mastocytosis
6. MPN/Overlap
7. B-ALL t(5;14)
8. L-HES / M-HES
9. CEL

Question 6

DDx for B-ALL with Myeloid Markers

Answer 6

1. BCR::ABL1 (CD13,CD33 and CD25)
2. KMT2A (CD15 and CD65)
3. IgH::IL3/t(5;14) (CD13, CD33 and CD123)
4. ETV6::RUNX1/t(12;21) (CD13, CD33)

Question 7

What is the differential diagnosis of SMZL?

Answer 7

• CLL
• Hairy cell leukemia
• Mantle Cell Lymphoma
• Follicular lymphoma
• Lymphoplasmacytic lymphoma

Question 8

DDx for B-cell neoplasms that do not express pan B-markers

2

Answer 8

1. CLL
2. PBL

Question 9

DDx for CD19/CD10 Positive B-cell neoplasms (CD5-)

6

Answer 9

1. B-ALL
2. Haematogones
3. FL
4. BL
5. DLBCL
6. MM

Question 10

DDx for CD19/CD5 Positive B-cell neoplasms (CD10-)

4

Answer 10

1. CLL
2. MCL
3. B-PLL (SBLwPN)
4. 5% of DLBCL

Question 11

DDx for CD19 Positive B-cell neoplasms (CD5 and CD10-)

2

Answer 11

1. HCLv
2. MZL (SMZL, NMZL, MALT)

Question 12

Cyclin D1 positivity

Answer 12

MCL

Question 13

Annexin 1 Positivity

Answer 13

HCL

Question 14

DDx for villous lymphocytes

5

Answer 14

1. HCL
2. SMZL
3. HCLv
4. BPLL
5. SDRPL

Question 15

DDx for HRS cells

6

Answer 15

1. HL
2. NLP HL and TCHR LBCL
3. EBV+ DLBCL
4. Peripheral T, NOS
5. Anaplastic large cells Lymphoma
6. 1’ DLBCL of CNS
7. 1’ mediastinal LBCL
8. 1’ Effusion lymphoma

Non neoplastic: Megs/Carcinoma

Question 16

DDx for CD30+ lymphomas

HL, BCL(5), TCL(5)

Answer 16

I. cHL

II. BCL
* Anaplastic variant of DLBCL
* ALK+ LBCL
* PBL
* 1’ effusion lymphoma
* Lymphomatoid granulomatosis

III. TCL
* ATCL
* PTCL, NOS
* ALCL
* Extranodal NK/TCL
* Enteropathy ass. TCL

Question 17

CHL subtypes tend to have a male predominance, with the exception of which subtype?

Answer 17

• Nodular sclerosing HL
  
  • slight female predominance

Question 18

What is the expression of OCT2 and BOB1

in CHL HS cells?

Answer 18

• absence of the transcription factor (OCT2) and its cofactor (BOB1)

Note: EMA is also negative in most cases

Question 19

How can CHL lymphoma be mistaken for ALCL

and what IHC helps differentiate the two well?

Answer 19

• if the CHL is rich in neopastic cells it can morphologically resemble ALCL
• IHC
  
  • CHL = PAX5 (+)
    
    • EMA and ALK protein (-)
  • Detection of EBV (LMP1) favors CHL over ALCL as well

Question 20

What is one of the most difficult d/d

with CHL to differentiate?

Answer 20

• DLBCL with anaplastic morphology and CD30 (+) cells
  
  • especially if it is within the mediastinum

Question 21

DDx for Intrainusoidal Growth Pattern

Answer 21

1. TLGL
2. NKLGL
3. Hepatosplenic TCL
4. SMZL
5. SDRP Lymphoma
6. SBCLwPN

Question 22

Presence of MYD88 mutations point to which entity instead of SMZL?

Answer 22

Lymphoplasmacytic lymphoma

Note: although rarely SMZL can have this mutation.

Question 23

Different causitive factors in MALT lymphoma?

Answer 23

• Gastric - H.Pylori
  
  • t(18;14)
  • Treatment = Eradication of H. Pylori (PPI, Clarithromycin, Amoxil/Metronidazole)
  • If they do not respond = RadioTx/Chemo
• Ocular - Chlamydia
• Skin - B. Burgdorferi
• Salivatory glands - Sjogren
• Thyroid - Hashimotos

Question 24

DDx for Lytic Bone Lesions

Go Shimla

Answer 24

1. Gauchers
2. Osteosarcoma
3. Systemic mastocytosis
4. HL/HLH
5. Infections
6. Mets/MM
7. Langerhans Histiocytosis
8. Adult TCL

Question 25

DDx for MProtein

Answer 25

1. PCNs 2. CLL 3. SMZL 4. LPL 5. MALT

Question 26

DDx for GC B-cell Neoplasms

Answer 26

1. DLBCL 2. BL 3. FL

Question 27

What are the clinical spectrum of neoplastic diseases associated with HTLV-1 infection?

Answer 27

* ATLL * LGL

Question 28

What are the non-neoplastic diseases associated with HTLV-1 infection ?

Answer 28

* HTLV-1 associated myelopathy (tropical spastic paraparesis) * HTLV-1 associated infective dermatitis * Other HTLV-1 Inflammatory Disorders * Uveitis * Thyroiditis * Pnemonitis * Myositis

Question 29

DDx of EBV+ Neoplastic conditions

Answer 29

1. HL 2. BL 3. DLBCL 4. PBL 5. Extranodal T/NK 6. Angioimmunoblastic T

Question 30

DDx for HepC virus associated neoplasms

Answer 30

1. SMZL 2. LPL/WM 3. Cryoglobulinaemia

Question 31

DDx for HHV8 virus associated neoplasms

Answer 31

1. 1' effusion lymphoma 2. Multicentric castlemans

Question 32

DDx for massive splenomegaly

Answer 32

1. CML and MPNs 2. Malaria 3. Gauchers 4. Lymphomas * Splenic B-cell lymphomas (SDRPSBcL, SBCLwPN) * Hepatosplenic TCL 5. Infective: TB, Schistosomiasis, Hepatitis 6. Inflammatory: Sarcoidosis, RA, SLE 7. Infiltration: Gauchers, Nieman Pick, Rosai Dorfman, Amyloid 8. Sequestration: SC

Question 34

If you think MDS-IB rule out...

Answer 34

1. AML 2. biTP53