Hairy cell leukemia

Question 1

Gene mutation seen in virtually all cases of HCL

Answer 1

BRAF V600E

Question 2

Presentation of HCL

Answer 2

Systemic complaints (25%) (fatigue, weakness, weight loss)
Bruising and bleeding (25%)
*B symptoms and adenopathy are uncommon
Abdominal fullness or discomfort (splenomegaly)
Asymptomatic (25%)

Question 3

diagnosis

Answer 3

BMB + flow cytometry and Typical immunophenotype of peripheral blood (usually dry tap with BMB) + typical clinical manifestations

Question 4

what is hairy cell variant of HCL?

Answer 4

variant that tends not to respond as well to purine nucleoside analog based therapy

Question 5

Indications for initiating therapy in HCL

Answer 5

symptomatic splenomegaly, b symptoms, recurrent infections, cytopenias (hgb<12, platelet count <100, ANC<1)

Question 6

efficacy of treatment for HCL

Answer 6

CR is achieved in most (70-90%)

relapse rate of approximately 30-40%)

Question 7

Treatment options for HCL

Answer 7

1) Cladribine

2) Pentostatin

Question 8

Typical response to therapy

Answer 8

Improvement in peripheral blood counts may require weeks to months.

Question 9

general treatment strategy

Answer 9

Observe if asymptomatic or no indications for treatment
Wait until symptomatic or severely cytopenic –> induction therapy single cycle of cladribine –> consolidation therapy

Question 10

cell of origin

Answer 10

B cell neoplasm

Question 11

clinical behavior

Answer 11

indolent

Question 12

Demographic

Answer 12

Males (4:1)

caucasions (3:1)

Question 13

Lab findings

Answer 13

Pancytopenia (60-80%)

Question 14

BMB findings with hairy cell

Answer 14

• commonly dry tap due to HCL-induced marrow fibrosis

Question 15

What is a trephine biopsy?

Answer 15

• tiny core of bone marrow tissue is removed then sliced very thinly.

Question 16

Infection disease hairy cell leukemia patients are at increased risk for

Answer 16

Nontuberculous mycobacterial infections

Question 17

Major cause of death in patients with HCL

Answer 17

Infection

Question 18

Medication class of pentostatin and cladribine

Answer 18

Purine analogues (antimetabolites)

Question 19

SE to know about with purine analogs

Answer 19

Profound neutropenia + lymphopenia (suppress immune effector cells)

Question 20

typical induction therapy

Answer 20

Single cycle of cladribine (5 or 7 day infusion)

Question 21

Consolidation therapy

Answer 21

Short course of rituximab

Question 22

Management of symptomatic splenomegaly

Answer 22

• splenectomy as palliative therapy

- salvage splenectomy if persistently pancytopenic

Question 23

Response assessment

Answer 23

• Serial CBCs for count recovery

- Monitor for signs of infection

Question 24

Typical response to purine analogs

Answer 24

Durable responses are seen in >90 percent of patients with a median progression-free survival (PFS) of 9 to 11 years.

Question 25

Primary major contraindication to purine analogs

Answer 25

active infection (given myelosuppression)

Question 26

markers

Answer 26

CD11C+

CD103+