Rick Allen

 A malignant proliferation of plasma cells derived from a single clone, with multifocal involvement of the skeleton.

 1,115 Aussies diagnosed every year  Risk increases w. age : 80% are > 60 y.o.  Men > women  Black 2x > white  Familial link (4x increased risk)  1% of all US cancers, 10% of haemotological cancers

 Cause is unknown, however there is evidence for genetic issues;  11q14 and 17p13 deletions (serious)  11q abnormalities  T(11;14)(q13;q32), cyclin D1 (cell cycle regulatory gene) (less serious)  T(4;14)(p16;q32) heavy chain gene and tyrosine kinase receptor  controls cell proliferation  Mys, ras, p53 and Rb-1 mutations

 Plasma cell attaches to bone marrow stromal cell (handy because…)  Monoclonal Ig (M component) is produced; potentially with excess heavy/light chains (urine)  Bone destruction (↑ RANKL on OB  ↑ OC act., inhibition of OB)  IL-6, IGF-1 the main players

 Are due to:  Plasma cell growth in tissue  Excessive defective Ig production  Normal humoral immunity suppression

 Bone resorption   pathologic fractures and bone pain (usually precipitated by movement). Generalized osteoperosis   hypercalcaemia  neurologic symptoms and renal dysfunction  ↓ normal Ig production   Recurrent bacterial infection  Cell immunity not affected  Ig breakdown increased  IgA  ↑ blood viscosity  headaches, retinopathy, fatigue  Renal failure  Multifactorial cause, but primarily due to Bence-Jones proteinuria  Toxic  atrophy of tubal epithelia, pyelonephritis  Anaemia  Due to marrow involvement. Normocytic, normochromic. Pancytopenia.

 Destructive plasma cell tumours in axial skeleton  Medullary cavity  erodes spongy bone  destroys cortical bone. Lesions 1-4cm diameter  Soft, gelatinous, red tumour mass  Elsewhere, ↑ marrow plasma cellularity

 Radiograph and lab results  24hr urine to find Bence-Jones bodies  Electrophoresis to determine monoclonal Ig/light chains  X-rays of osteolytic lesions: require bone marrow examination to confirm.

 Some lymphomas and leukaemias (CLL) can also produce M components.

 Systemic treatment + symptomatic treatment  Cytotoxic agents (proteasome inhibitors)  Combination chemo: alters myeloma and stromal cell interaction. Inhibits angiogenesis  Bisphosphonates  bone and Ca  Transplant: prolongs but no cure  Radiotherapy for bone pain

 Median survival 4-6 years  Multiple bony lesions  6-12 months  Death usually due to either renal failure or infection

 Plasmacytoma  Localised myeloma  Have the potential to spread. Easier to treat if found in soft tissue.  Monoclonal Gammopathy of Uncertain Significance (MGUS)  Same genetic abnormalities as MM  Asymptommatic w. elevated M components.  Progression to MM ~1%. Unpredictable.

 Robbins and Cotran, pp  Harrisons, pp  Underwood, pp  Leukaemia association of Australia  Up to Date