Myeloma

Question 1

What is it?

Answer 1

Multiple myeloma (MM) is a haematological malignancy characterised by plasma cell proliferation.

It arises due to genetic mutations which occur as B-lymphocytes differentiate into mature plasma cells.

Question 2

Clinical features

age

Answer 2

The median age at presentation is 70-years-old.

Use the pneumonic [CRABBI]:

CALCIUM

• Hypercalcaemia occurs as a result of increased osteoclast -activity within the bones
• CF: constipation, nausea, anorexia and confusion

RENAL impairment caused by:

• Monoclonal production of immunoglobulins results in light chain deposition within the renal tubules
• Amyloidosis

ANAEMIA

• Bone marrow crowding suppresses erythropoiesis leading to anaemia
• CF: fatigue and pallor

BLEEDING
- Bone marrow crowding also results in thrombocytopenia which puts patients at increased risk of bleeding and bruising

BONES

• Bone marrow infiltration by plasma cells and cytokine-mediated osteoclast overactivity creates lytic bone lesions
• CF: back pain and increased risk of fragility fractures

INFECTION
- a reduction in the production of normal immunoglobulins results in increased susceptibility to infection

Question 3

Investigation

Answer 3

FBC: anaemia and thrombocytopenia (FBC)

U+Es: raised urea and creatinine (U&E) and raised calcium

SERUM & URINE PROTEIN ELECTROPHORESIS:

• raised concentrations of monoclonal IgA/IgG proteins will be present in the serum
• In the urine, they are known as Bence Jones proteins

BLOOD FILM:
- rouleaux formation

BONE MARROW ASPIRATION + TREPHINE BIOPSY: - confirms the diagnosis if the number of plasma cells is significantly raised ( >10% )

WHOLE BODY MRI(or CT if MRI is not suitable) is used to survey the skeleton for bone lesions

A common X-ray finding is a ‘rain-drop’ skull. This is numerous randomly placed dark spots seen on X-ray which occur due to bone lysis.

Question 4

Management

Answer 4

Autologous stem cell transplant is removal of a patient’s own stem cells prior to chemotherapy, which are then replaced after chemotherapy

For patients who are suitable for autologous stem cell transplantation induction therapy consists of:
Bortezomib + Dexamethasone

For patients who are unsuitable (old, co-morbidities) for autologous stem cell transplantation, induction therapy consists of :
Thalidomide + an Alkylating agent + Dexamethasone