Objective: To evaluate the effect of antileukemic chemotherapy adminis
tered at diagnosis on the survival of patients with isolated chloroma.
Design: Retrospective review of locally identified patients and analy
sis of cases from the medical literature. Patients: The records of all
patients with isolated chloroma identified at three teaching hospital
s in Toronto between 1980 and 1994 were reviewed. A MEDLINE search was
done to identify all cases of isolated chloroma reported in the Engli
sh-language medical literature. Patients with a previous known hematol
ogic disorder were excluded. Measurements: The effect of therapy on 1)
the interval between diagnosis of chloroma and diagnosis of acute mye
loid leukemia and 2) survival was determined.Results: 7 local patients
and 83 published cases were identified, for a total of 90 evaluable p
atients. For the entire group, the median time to the diagnosis of acu
te myeloid leukemia was 9 months, and median survival was 22 months. C
hemotherapy was administered to 49 patients (54%) at diagnosis of chlo
roma. Significantly fewer patients treated with chemotherapy subsequen
tly developed acute myeloid leukemia (41% compared with 71%; P = 0.001
). Survival was longer in patients treated with chemotherapy (>50% ali
ve with a median follow-up of 25 months compared with a median surviva
l of 13 months for those initially untreated; P = 0.001). Multivariate
analysis showed that neither local radiotherapy nor surgery had an ef
fect on survival. Conclusions: Administration of antileukemic chemothe
rapy at diagnosis of chloroma is associated with a significantly lower
probability of developing acute myeloid leukemia and with longer surv
ival.