Haematology Vignettes – 23

A case of plasma cell myeloma in a middle aged male

A 53-year-old male was referred to the Haematology clinic with severe back pain together with a normochromic, normocytic anaemia for investigation. A full blood count was performed with the following results:
Hb 108 x g/L, WBC 4.5 x 109/L, platelet count 227 x 109/L and ESR of 125 mm/hr.

The blood film confirmed a normochromic, normocytic anaemia with a marked increase in rouleaux formation. The white cells and platelets were normal in number and morphology.

Serum proteins were performed. A paraprotein IgGk of 91g/L was identified by immunofixation in the beta globulin region.

Bence Jones protein, 3.49 g/24hr, was found in the urine.

A bone marrow aspiration was performed. There was a heavy infiltrate of plasma cells displacing much of the normal haematopoietic tissue of the marrow. The plasma cells were large with eccentrically placed nuclei and basophilic cytoplasm. Binucleate forms were frequent. Mitotic figures were also increased.

A bone marrow trephine showed a similar picture.

A diagnosis of plasma cell myeloma was made.

Immunophenotyping on the marrow showed the following:
CD19, CD20, CD138+, CD38+, and CD79a+

Bone marrow trephine showing sheets of plasma cells

Bone marrow biopsy showing sheets of plasma cells

Bone marrow biopsy showing sheets of plasma cells

Bone marrow trephine showing a heavy infiltrate of plasma cells

Bone marrow trephine showing a heavy infiltrate of plasma cells

Plasma cell myeloma is a neoplasm occurring more commonly in males. The median age at presentation is 50 years. The initial presentation is associated with bone pain, back, neck and pelvic pain. Radiographic findings reveal lytic lesions and osteoporosis. Pathological fractures can occur in up 70% of patients.

Plasma cell myeloma is diagnosed from the bone marrow. It is invariably associated with a paraprotein or M-protein in the serum and/or the urine. The protein in the urine is referred to as Bence Jones protein.

Symptomatic plasma cell myeloma is associated with CRAB: hypercalcaemia, renal insufficiency, anaemia and bone lesions.

The peripheral blood shows an increase in rouleaux formation. Plasma cells are found in approximately 15% of cases and only in small numbers.

The bone marrow shows an increase in plasma cells, more than 3% and sometimes up to 90%. Mature plasma cells are oval to round in shape with round eccentric nuclei. The cytoplasm is basophilic with a perinuclear hof. Crystals as well as globules of immunoglobulin are sometimes seen in the cytoplasm. Plasma cells appear in clusters or sheets within the marrow with preservation of normal haematopoiesis.

When the number of plasma cells in the peripheral blood exceeds 2 x 109L the neoplasm is referred to as plasma cell leukaemia.

Plasma cell myeloma is usually incurable. It has a median survival of 3-4 years. Transplantation may be attempted to increase and prolong quality of life.

The patient in this case study remains well.