Melphalan


Nitrogen mustard class cytostatic alkylating agent, used as a first line drug in the treatment of multiple myeloma.
 
Incidence
2.4% (intravenous route).
 
Uncommon when administered orally (0.3%).
 
No deaths reported.
 
Risk factors
IgA multiple myeloma (55% of cases).
 
Intravenous route.
 
Clinical manifestations (at least 2 prior doses, up to 28 previous doses).
General: anaphylactic shock.
 
Cutaneous: urticaria, angioedema, rash, pruritus.
 
Respiratory: interstitial pneumonitis.
 
Diagnostic methods
Leukocyte migration inhibition test: one positive test in a case of interstitial pneumonitis.
 
Mechanisms
Alkylation reaction may occur in vivo, and altered proteins may serve as new antigens capable of stimulating antibodies to the hapten-protein complex.
 
Management
Avoidance of the intravenous route. Some reactive patients may be switched to oral melphalan with no further reaction.
 
Cross reactivity with other alkylating agents is exceptional (cyclophosphamide).
 

References

  1. Weiss R.B, "Hypersensitivity reactions", Semin.Oncol., 1992; 19 (5):
    458-77
  2. Liote H, Gauthier J.F, Prier A, Gauthier-Rahman S, Kaplan G, Akoun G, "Pneumopathie interstitielle, aigüe, réversible, induite par le melphalan", Rev. Mal. Respir., 1989; 6 (5): 461-4
  3. Lawrence B.V, "Anaphylaxis due to oral melphalan", Cancer, Treat. Rep., 1980; 64 (4-5): 731-2
  4. Cornwell G.G. III, Pajak T.F, Mc Intyre O.R, "Hypersensitivity reactions to IV melphalan during treatment of multiple myeloma: Cancer and Leukemia Group B experience", Cancer. Treat. Rep., 1979; 63 (3): 399-403

As in all diagnostic testing, the diagnosis is made by the physican based on both test results and the patient history.