5-Azacytidine Before or After Stem Cell Transplantation in Acute Myeloid Leukaemia (AML) and Myelodysplastic Syndromes (MDS)

From 2007 to 2011, 15 patients (11 males, 4 females) received 5-aza as last treatment prior to an allogeneic SCT (n=13) or as rescue after an early post-transplant relapse (n=2) at our centre. Diagnosis was MDS in 3 cases (median age 62; range 58–63) and AML in 12 cases (median age 58; range 37–67). Patients with MDS received a median of 6 courses of 5-aza (range 3–8) as the only treatment from diagnosis, except for one patient who had received panobinostat prior to 5-aza. Amongst patients with AML, 12 patients received 5-aza either as treatment for AML (2/12) or after remission (8/12) because of the high relapse risk while awaiting for a suitable donor to be found. Two patients with AML received 5-aza as treatment for early post-SCT relapse. AML patients treated with 5-aza before SCT received a median of 5 courses (range 1–19), whilst patients receiving treatment for relapse received 1 and 3 courses, respectively. Ten patients received a nonmyeloablative conditioning regimen, 1 received a conventional conditioning regimen, 2 patients are still in the process of donor search and the other 2 patients received 5-aza after an autologous stem cell transplantation relapse.

All MDS patients engrafted and are in complete remission (CR) after a median of 696 days of follow-up (range 377–1227). One of those patients died because of aGvHD. Nine of 12 AML patients receiving 5-aza prior to SCT are alive after a median 373 days follow-up (133–995). One patient showing refractoriness to 3 different lines of treatment died from disease progression after 211 days. All patients receiving 5-aza as treatment for early relapse are dead, 41 and 401 days after starting treatment. Most interestingly, AML patients receiving 5-aza as maintenance of an already-achieved CR while awaiting transplantation did not experience disease progression despite the median time they remained on this treatment was prolonged (9 months). Graft-versus-host disease ≥ grade II was seen in 3 patients. No graft failures were seen and all patients who received an allogeneic stem cell transplantation remain in complete response.

The use of 5-aza for maintaining or achieving a response in patients with AML who are awaiting SCT is a safe procedure and adds flexibility to schedule the treatment without the need to administer potentially toxic therapy. The use of 5-aza before transplant did not appear to interfere either with engraftment, incidence of GvHD or short-term relapse after transplant.

No relevant conflicts of interest to declare.