Allogeneic stem cell transplant (SCT)

Patients with high-risk disease who are young enough and fit enough may undergo allogeneic SCT. This represents the only potential cure for CMML. Hypomethylating agents like azacitidine and decitabine are usually given prior to allogeneic SCT for cytoreduction or to ameliorate cytopenias.[21,22] Retrospective reports that included small numbers of patients with CMML (range, 12–80) who underwent allogeneic SCT reported recurrence rates of 20% to 40% and 5-year overall survival (OS) rates of approximately 20% to 30%.[23-28][Level of evidence C3]

A retrospective review of 1,114 patients with CMML diagnosed between 2000 and 2014 included 384 patients who underwent allogeneic SCT.[29] With a median follow-up of 51 to 78 months (in two data sets), allogeneic SCT in patients with low-risk CMML was detrimental, with a 5-year OS rates of 20% for patients who underwent allogeneic SCT and 42% for patients who did not undergo allogeneic SCT (P < .001).[29][Level of evidence C1] For patients with high-risk CMML, there was no statistically significant difference in 5-year OS rates among patients treated with or without allogeneic SCT (27% vs. 15%, respectively; P = .13).