W4- L6-NON-HODKIN LYMPHOMA

Question 1

Constitutes a heterogeneous group of lymphoid malignancies that vary widely in their biological behavior and clinical presentation

Answer 1

NHL

Question 2

What is the impact of environmental factors on NHL?

Answer 2

Incidence appears to be increasing due to
environmental factors (viruses, iatrogenic immunosuppression, occupational - exposure
to insecticides/pesticides etc.)

Question 2

More common than Hodgkin lymphoma (accounts for ±80% of all lymphomas)

Answer 2

NHL

Question 3

What are the AETIOLOGICAL / PREDISPOSING
FACTORS of NHL?

Answer 3

1. Immunodeficiency
   Congenital – ataxia telangiectasia etc.
   Acquired - HIV/AIDS
2. Viruses
   HIV; HTLV-1; EBV; Hepatitis C; HHV-8
3. Helicobacter pylori – Malt lymphomas
4. Gluten induced enteropathy – T cell NHL
5. Occupational factors: hydrocarbon solvents, pesticides
6. Chemotherapy or radiotherapy
7. Autoimmune disease
8. Other

Question 3

Outline the pathogenesis of NHL

Answer 3

• Pathogenesis of NHL is a multi-step process that includes:

-genetic predisposition,
-possible viral infection
-chronic immune stimulation,
-cytokine dysregulation

Question 3

What’s the Commonest haematological malignancy in adults; particularly in areas of HIV seroprevalence?

Answer 3

NHL

*Aggressive subtypes in association with HIV –
AIDS defining malignancy

Question 4

Comment on the incidence of NHL

Answer 4

• It increases with age. Average age 40-60 years
• Certain subtypes commoner in elderly:
  a). mantle cell lymphoma and
  b) small lymphocytic lymphoma

Younger individuals;
(a) Burkitt
lymphoma)

Geographical – certain subtypes more common in particular geographical locations (e.g.
Burkitt’s lymphoma - central Africa, ATLL –Japan)

Question 5

Outline the lymphocyte ontogeny

Answer 5

Pluripotent stem cells»lymphoid stem cell (B or T cells)» Early B cells» intermediate B cells»mature B cells»secretory B cells

Question 6

How to manage NHL?

Answer 6

• Individualized management: Based on age, performance
  status, stage, histological subtype, blood
  counts, symptoms etc.
• Multidisciplinary team. Some patients ‘watch and
  wait’ approach (especially with low grade
  histology; elderly)

1. SUPPORTIVE
   e.g. Analgesia, Blood and blood products, Antibiotics, Correction of electrolyte imbalance, Growth factors, Psychosocial,
   Antiretrovirals, etc
2. SPECIFIC:

a).Chemotherapy (single agent or combination chemotherapy e.g. CHOP/R-
CHOP = Cyclophosphamide,
hydroxydaunorubicin/adriamycin, vincristine/ oncovin, prednisone, rituximab)
-Other chemotherapy regimes incoporating
cytosar, methotrexate, etoposide, platinum
compounds etc.

b. Radiotherapy
c. Surgery
d. Immunotherapy
e. Stem cell transplantation
f. Intrathecal chemotherapy
g. Novel and experimental therapies

Question 6

What are the clinical features of NHL?

Answer 6

Nodal, extranodal, paraneoplastic:

1. Lymphadenopathy
   (Peripheral, central. Localized/generalized. Significant/shotty.
   Sites. Other characteristics)
2. Hepatosplenomegaly
3. Constitutional symptoms (less frequent than HD)
4. Cytopenias (Bone marrow involvement, immune,
   hypersplenism, therapy, nutritional, HIV etc.)
5. Extranodal disease – more common with HIV
   (GIT, CNS, skin, testis, etc.)
6. Paraneoplastic

*Clinical staging is based on the Ann-Arbor staging

Question 6

What are the neccessities to investigate for NHL?

Answer 6

a). Establish the diagnosis
1. Histological diagnosis
lymph node biopsy (mandatory if no exception).
Biopsy of non-nodal tissue where node is not enlarged or
inaccessible

b). Define the extent of spread (stage)
1. Clinical disease
2. Blood
FBC with diff; U&E; LFT&LDH; Uric acid; CMP; HIV; Beta-2
microglobulin etc.
3. Radiological
CXR; CT scan (head,neck, chest, abdomen, pelvis)
4. Bone marrow aspirate and trephine
5. Flow cytometry, cytogenetics and FISH, gene
rearrangement studies (blood/BM/tissue)