Melphalan treatment in patients with myelofibrosis with myeloid metaplasia

Between January 1985 and December 1992, 104 consecutive patients with symptomatic myelofibrosis with myeloid metaplasia (MMM) [splenic enlargement > 5 cm and/or transfusional requirement or Hb 20 × 109/l and/or platelets > 1·0 × 109/l] received low‐dose Melphalan (2·5 mg/3 times/week) to evaluate the efficacy and toxicity of this approach. Among 99 evaluable patients, 66 (66·7%) achieved a response after a median time of 6·7 months: 26 (26·3%) had a normalization of all clinical and haematological parameters (complete response, CR) and 40 (40·4%) showed an improvement > 50% (partial response, PR). Thirty‐three patients (33·3%) were resistant. Reversible haematological toxicity was the most common complication. Median durations of CR and PR were 28·4 and 26 months respectively: median survival of CR + PR patients was 71·2 months (95%CI: 33·8–108·7) versus 36·5 months (95%CI: 24·5–48·5) for the non‐responders (log‐rank test, P = 0·002). In the multivariate analysis, the following variables were significantly associated with a shorter survival: anaemia [hazard risk (HR) = 2·7], WBC count > 20 × 109/l (HR = 2·4) and not achieving any type of response, either partial or complete (HR = 3·9). In conclusion, Melphalan could be a promising first‐line option for MMM patients with clinical or haematological symptoms requiring treatment.