Abstract
BACKGROUND:
Acute lymphoblastic leukemia (ALL) occurring in patients with a history of prior chemotherapy/radiotherapy exposure has been previously reported to be rare, accounting for <2.5% of ALL cases.
METHODS:
All cases of adult ALL with a history of prior cytotoxic or radiation therapy at a leukemia referral center over a 13‐year period were analyzed.
RESULTS:
Twenty‐three cases, representing 6.9% of all ALL cases, were identified. Of these, 17 (74%) had at least 1 high‐risk feature; 8 (35%) had MLL rearrangements, and 4 were BCR‐ABL^+^. MLL rearrangements were correlated with CD15 expression and absence of CD10, and also tended to have a shorter mean latency period and more prior topoisomerase II exposure. Twenty‐one patients received induction therapy, and 18 (86%) achieved a complete response, 17 with 1 induction. Six patients have relapsed and died, and 4 others died of other complications, 2 of these postallogeneic stem cell transplantation. Median disease‐free survival (DFS) and overall survival (OS) were 27 and 13.6 months, respectively, and 3‐year DFS and OS were 37.1% and 37.6%, respectively.
CONCLUSIONS:
The frequency of therapy‐related ALL is higher than previously reported and has a poor prognosis, probably related to the high frequency of adverse risk features. Cancer 2012. © 2011 American Cancer Society.