Myeloma

Repression of multiple myeloma growth and preservation of bone with combined radiotherapy and anti-angiogenic agent

The effects of ionizing radiation, with or without the anti-angiogenic agent anginex (Ax), on multiple myeloma growth were tested in a SCID-rab mouse model. Mice carrying human multiple myeloma cell-containing pre-implanted bone grafts were treated weekly with various regimens for 8 weeks. Rapid multiple myeloma growth, assessed by bioluminescence intensity (IVIS), human lambda Ig light chain level in serum (ELISA), and the volume of bone grafts (caliper), was observed in untreated mice. Tumor burden in mice receiving combined therapy was reduced to 59% (by caliper), 43% (by ELISA), and 2% (by IVIS) of baseline values after 8 weeks of treatment. Ax or radiation alone slowed but did not stop tumor growth. Four weeks after the withdrawal of the treatments, tumor burden remained minimal in mice given Ax + radiation but increased noticeably in the other three groups. Multiple myeloma suppression by Ax + radiation was accompanied by a marked decrease in the number and activity of osteoclasts in bone grafts assessed by histology. Bone graft integrity was preserved by Ax + radiation but was lost in the other three groups, as assessed by microCT imaging and radiography. These results suggest that radiotherapy, when primed by anti-angiogenic agents, may be a potent therapy for focal multiple myeloma.

Myeloma Presenting in the Base of the Skull

Of 385 consecutive patients with a proven diagnosis of myeloma seen over a 15 year period, only four presented with symptoms and signs due to involvement of the skull base. This rare occurrence is in striking contrast to the frequency with which radiologic changes can be demonstrated in the bones of the calvarium during the course of most individual's disease. Response to treatment was obtained in all four, of whom one is a longterm survivor. This experience is reported emphasising the need to consider the possibility of myeloma in people with unexplained craniospinal symptoms and signs. In addition, the radiologic changes are tabulated in the hope that a pattern may emerge which will alert physicians to the presence of this rare situation.

Multiple myeloma

OBJECTIVES

To review the epidemiology, pathogenesis, clinical features, diagnosis, treatment, and nursing management of multiple myeloma.

DATA SOURCES

Review articles, research studies, and book chapters related to multiple myeloma.

CONCLUSIONS

Despite insights into the immunobiology of multiple myeloma and the advances in intensive therapy and supportive care, multiple myeloma remains an incurable disease. Patients will experience chronic and acute symptomatic episodes throughout the course of their disease.

IMPLICATIONS FOR NURSING PRACTICE

Oncology nurses can assist patients with multiple myeloma and their families to manage both the disease and treatment related symptoms and to improve their overall quality of life. Specific nursing assessments can provide early recognition of complications, such as hypercalcemia and spinal cord compression.

Assessment of the therapeutic potential of cytokines, cytotoxic drugs and effector cell populations for the treatment of multiple myeloma using the 5T33 murine myeloma model

The therapeutic potential of six cytokines, eight cytotoxic drugs and two effector cell populations for the treatment of multiple myeloma was assessed in vitro using the 5T33 murine myeloma model. The efficacy of combination IFN-alpha and melphalan therapy was also evaluated in vitro and in vivo. Of the cytokines tested in vitro using the MTT assay, only IFN-alpha demonstrated significant inhibition of myeloma cell growth at non-toxic concentrations (ED50 = 1508.3 +/- 181.3 U/mL and 2617.9 +/- 334.0 U/mL for murine IFN-alpha [mIFN-alpha] and human IFN-alpha hybrid B/D [hIFN-alpha B/D], respectively). The ED50 for the eight cytotoxic drugs tested ranged from 2.3 x 10(-9) to 4.3 x 10(-13) mol/L and all were within the therapeutic range for humans. Combination hIFN-alpha B/D and melphalan were found to be additive in their inhibitory effects on myeloma cell growth in vitro and this finding was confirmed in vivo in C57BL/KaLwRij mice bearing disseminated 5T33 myeloma. Control animals demonstrated a median survival duration of 25.3 days whereas hIFN-alpha B/D or melphalan treatment alone increased survival to 30.5 and 33.3 days, respectively (P < 0.001). Combination IFN-alpha/melphalan therapy increased median survival duration to 38.5 days (P < 0.001) which was also significantly greater than that obtained with single agent therapy (P < 0.01). The murine myeloma cells were found to be resistant to NK cell lysis but susceptible to lysis by LAK cells (49.3 +/- 6.3% lysis at an effector to target ratio of 100:1).(ABSTRACT TRUNCATED AT 250 WORDS)