Mature T cell lymphoma\leukemia

Classic presentation of T-PLL?

Remember: “5 S’s”

• Severe leukocytosis

• Splenomegaly (hepatosplenomegaly)

• Skin lesions

• Swollen lymph nodes (lymphadenopathy)

• Serous effusions

Most common extramedullary site of T-PLL?

✅ Skin

• Dermal infiltrate

• Predominantly perivascular

• No epidermotropism

Peripheral blood morphology in T-PLL?

A:

• Medium-sized prolymphocytes

• Condensed chromatin

• Single prominent nucleolus

• Basophilic cytoplasm

• Cytoplasmic blebs

Characteristic immunophenotype of T-PLL?

✅ CD2+
✅ CD3+
✅ CD5+
✅ CD7 (strong)
✅ CD52
✅ TCL1+

❌ TdT negative

Hallmark cytogenetic abnormality of T-PLL?

A:

✅ inv(14)(q11;q32)

Major diagnostic criteria for T-PLL?

A:

Need:

• ≥5 × 10⁹/L T-PLL cells

• Clonal T-cell population

• TCL1A/B or MTCP1 abnormality

What is the first-line treatment for T-PLL?

A:

✅ Alemtuzumab (anti-CD52) ( IV over SC)

Which infection prophylaxis is mandatory during alemtuzumab?

A:

• PCP prophylaxis

• Herpesvirus prophylaxis

• Weekly CMV monitoring

Only curative treatment for T-PLL?

.

A:

✅ Allogeneic hematopoietic stem cell transplantation

Should be offered in first remission to eligible patients

vTreatment options for relapsed T-PLL?

A:

• Repeat alemtuzumab (if remission >6 months)

• Nelarabine

• Bendamustine

• Pentostatin

• Alemtuzumab + pentostatin

• FMC-A

• Ibrutinib + venetocla

Most common mutation in T-LGLL?

STAT3 (28–75%)

Classic immunophenotype of T-LGLL?

Back
CD3+
CD8+
CD57+
CD16+
TIA-1+
Granzyme B+
Dim CD5/CD7
CD56−
CD28

Most common indication for treatment?

Severe neutropenia (ANC <0.5 ×10⁹/L) with recurrent infections

First-line drugs for T-LGLL?

Methotrexate
Cyclophosphamide
Cyclosporine

A 67-year-old woman with long-standing rheumatoid arthritis presents with recurrent bacterial sinus infections. CBC shows Hb 10.8 g/dL, ANC 0.3 ×10⁹/L, lymphocytes 5.5 ×10⁹/L. Flow cytometry reveals CD3+, CD8+, CD57+, CD16+, dim CD5 expression. Which molecular abnormality is most commonly associated with this disorder?

A. BRAF V600E
B. STAT3 mutation
C. JAK2 V617F
D. MYD88 mutation
E. TP53 deletion

Answer: B. STAT3 mutation

Explanation: STAT3 gain-of-function mutations are found in 28–75% of T-LGLL and drive constitutive JAK/STAT signaling. The other mutations are characteristic of different hematologic malignancie

spot diagnosis?

T LGLL

Which virus is classically associated with ANKCL?

Epstein-Barr virus (EBV).

Which immunophenotype is characteristic of ANKCL

• CD2+

• CD56+

• Cytoplasmic CD3ε+

• Surface CD3−

• Granzyme B+

• Perforin+

• TIA-1+

Q: What is the TCR configuration in ANKCL?

Germline (no TCR rearrangement).

Which mutation is most characteristic of ANKCL?

 STAT3 mutation.

Which mutation favors ENKTL instead?

JAK3 mutation.

Preferred induction therapy ANKL?

L-asparaginase-based chemotherapy (Modified SMILE). followed by allo

Question 2

Which immunophenotype is most consistent with ANKCL?

A. Surface CD3+, CD5+, CD57+

B. CD19+, CD20+, CD79a+

C. CD2+, CD56+, cytoplasmic CD3ε+, surface CD3−

D. CD10+, BCL6+, CD20+

E. CD30+, ALK+

Answer: C