CLL (BSH 2018)

CD5+, CD23+, Surface Ig weak+, Strong CD43+, CD200+

CD79b -, FMC7-

 

Intro

 

Incidence 4.2 per 100,000 per year in UK

Median age of presentation 72

Men > Women

Caucasian > other ethnic groups

>80% incidental diagnosis

 

Diagnosis

 

>5 x109/l circulating clonal B cells persisting for >3 months and of characteristic immunophen.

 

CLL Score (now outdated as different CD proteins often used)

–      Surface Ig weak, CD5+, CD23+, CD79b-, FMC7-. One point for each. 92% of CLL scores 4 or 5

 

Prolymphocytes:

<15% (CLL), 15-55% (CLL/PL), >55% (B-PLL)

 

DDx for CD5+ LPD with a low score = atypical CLL, mantle cell, marginal zone

 

cMBL = clinical CD5+ monoclonal B cell lymphocytosis

-       MBL detectable on a routine FBC but <5 x109/l monoclonal cells

-       WHO 2016 splits <0.5x109/l (no concern) from 0.5-5 x109/l (annual FBC monitoring)

 

Staging

 

BINET

-       A: <3 lymphoid areas

-       B: 3 or more lymphoid areas

-       C: Hb <100 or Plt <100

-       (Five lymphoid areas are: uni or bilat. cervical, axillary, inguinal, hepatomeg, splenomeg)

 

RAI

-       0: Low risk: Lymphocytosis only

-       I: Intermediate: Lymphadenopathy

-       II: Intermediate: Hepatomeg or splenomeg + lymphocytosis

-       III/IV: High risk: Hb <110 or Plt <100

 

Investigations

 

Asymptomatic Stage A patients

-       FBC, reticulocyte, DAT, biochemistry, immunoglobulins, Hep B/C, HIV

-       Flow cytometry

-       TP53 deletion (FISH)

-       Lymph node biopsy only if diagnostic uncertainty

-       CT not required at diagnosis (perform later pre-treatment)

 

Diagnosing transformation

-       5-15% of CLL transforms to DLBCL-like or HL-like

-       May be localized, biopsy the suspicious site

-       PET-Ct may help identify best biopsy site.

 

Assessing prognosis

-       Binet / Rai systems predict outcome in advanced stage patients, but poor for early stage

-       Other factors:

o   Age, Gender, PS, co-morbidities

o   Marrow failure, immunodeficiency, autoimmunity, biomarkers

o   Type of treatment, Response, Toxicity, MRD status

-       Prognostic data should not influence timing of first treatment

-       Biomarkers include IGHV gene analysis, B2M, CD38 positivity

 

TP53

TP53 loss (17p del) occurs in 5-10% of patients at diagnosis, 30% in fludarabine refractory patients

TP53 mutation occurs in an additional 5% at diagnosis, 12% of refractory patients

Both TP53 loss and mutation are associated with lower response rates and short PFS when treated with chemoimmunotherapy (e.g. FCR or R-Benda).

—> Test TP53 status prior to each line of therapy and consider alternative treatments if detected, e.g. alemtuzumab or ibrutinib, which have TP53-independent mechanism of action.

IGHV

IGHV gene mutations confer a better prognosis, with prolonged remissions in response to chemoimmunotherapy.

‘IGHV unmutated’ is associated with a poorer prognosis.

Current guidelines recommend considering analysis of IGHV mutation status

Management

 

NOT indications to treat - High lymphocyte count (in absence of rapid doubling time), hyperviscosity and hypogammaglobulinaemia (in absence of recurrent infection)

 

Indications to treat:

-       Lymphocyte doubling time <6 months (provided starting Lymph count >30)

-       Lymphocyte count increased >50% in 2 months

-       Progressive marrow failure

-       Massive (>6cm below costal margin) splenomegaly

-       Massive (>10cm) lymph nodes

-       Autoimmune anaemia / thrombocytopenia not controlled by standard therapy

-       Constitutional symptoms

o   Wt loss >10% in 6 months, fatigue (PS 2 or worse), Fever >38 for 2 weeks, night sweats for >1 month.

 

Choosing therapy

-       No single choice, patient-by-patient

-       Age, co-morbidities, creatinine clearance, PS, susceptibility to infection

-       Important to achieve maximal response

o   Achieving MRD negative remission is an independent marker for OS and PFS

 

Defining response

-       IWCLL criteria for CR, PR and progressive disease

-       Relapse = disease progression at least 6 months after achieving CR / PR

-       Refractory = treatment failure or disease progression less than 6 months after CR/PR

 

CLL response.jpeg

 

 

Treatment not required for Early / Stage A Disease

-       6 monthly review in first year to assess rate of progress

-       Then annually if no concern, GP or hospital

-       Address patient and family concerns around leukaemia diagnosis and implications

 

Treatment Principles

-       Irradiated blood products

o   For life: purine analogies, bendamustine, campath

o   3 months post-conditioning for autograft

-       See ukcllforum.org for up to date NICE licensing information

-       MDT approach

- Offer clinical trial

 

Front-line: Current Guidelines

Fit patients without TP53 abnormality

  • FCR first choice (CLL8, CLL10, ARCTIC and ADMIRE)

  • R-Benda an alternative if specific co-morbidities prevent FCR use

Not fit patients without TP53 abnormality

  • Chlorambucil-Obinotuzumab (CLL11 - PFS and TTNT benefit vs R-Chlormabucil)

  • Chlorambucil-Ofatunumab (COMPLEMENT-1)

  • R-Bendamustine an acceptable alternative

  • Ibrutinib an acceptable alternative (but not NICE approved)

  • (R-Chlorambucil is not recommended as shown to be inferior to the above)

Patients with TP53 disruption (deletions and/or mutations)

  • Ibrutinib - NICE approved

  • R-Idelalisib - acceptable alternative if specific issues prevent ibrutinib use (e.g. cardiac disease, warfarin use)

Maintenance?

  • No

  • Anti-CD2- antibodies and lenalidomide have been trialed - increase PFS but no effect on OS seen, and need to weigh the long-term toxicity

Relapse/Refractory: Current Guidelines

Relapse after a prolonged remission in fit patients without TP53 abnormality

  • Consider re-treating with chemoimmunotherapy (FCR or R-Benda)

When to avoid further chemoimmunotherapy?

  • Refractory to prior chemoimmunotherapy

  • Relapse within 2-3 years of FCR or R-Benda

  • Acquired TP53 disruption

  • Co-morbidities preventing delivery of chemoimmunotherapy

—> And so, in this setting:

  • Ibrutinib or R-Idelalisib are treatments of choice

Failed or unsuitable for BCRi therapy

  • Venetoclax (via Cancer Drugs Fund)

When to consider allogeneic stem cell transplant?

  • Fit patients who have failed chemoimmunotherapy and BCRi

  • Fit patients with Richter transformation

 

Supportive Care

-       Prophylactic antibiotics for hypogammaglobulinaemia with recurrent infections

-       PCP prophylaxis with intensive treatments or on treatment for relapsed disease

-       Aciclovir prophylaxis with intensive treatment or low CD4 counts

-       CMV monitoring post-alemtuzumab

-       Consider immunoglobulin replacement 3-4 weekly if low IgG and recurrent infection. Discontinue after 1 year if not reduction in rates of infection.

-       Annual flu vaccination

- Pneumococcal vaccination - Prevnar followed by Pneumovax 2 months later

Drugs: A few notes

B-Cell Signalling Pathway Receptor Inhibitors (BCRi)

  • Bruton Tyrosine Kinase inhibitors (BTKi) - Ibrutinib

    • Causes acquired platelet function defect, beware of bleeding with interventional procedures / surgery

    • May trigger AF, VT and hypertension

    • Avoid CYP3A4 inhibitors - warfarin, fish oils, Vitamin E, St Johns Wort

    • Grapefruit and Seville oranges must be avoided

  • PI3 Kinase Inhibitors (PI3Ki) - Idelalisib

    • May trigger life-threatening pneumonitis or colitis

    • Monitor liver function

    • Monitor CMV PCR’s

    • Use PCP prophylaxis

BCL2 inhibtior - Venetoclax

  • Significant risk of tumour lysis

An increase in total lymphocyte count is commonly seen with use of new agents and reflects responding disease not progression.