Survivorship In AML - Outcomes Of Acute Myelogenous Leukemia (AML) Patients (pts) After Maintaining Complete Remission (CR) For At Least 3 Years

Approximately 80% of younger patients and 50% of older patients with newly diagnosed AML achieve CR after induction chemotherapy. The majority of patients who achieve CR eventually relapse, with most relapsing within the first 3 years. Long-term outcomes in pts maintaining 1^st CR for at least 3 years (AML survivors) remain largely unknown. The purpose of this study was to investigate long-term outcomes in this subset of pts.

We performed a chart review of pts with AML treated at our institution who achieved CR for at least 3 years after their initial chemotherapy ± allogeneic stem cell transplant (ASCT) to analyze their long-term outcomes.

1792 pts with AML were treated between 2000 and 2010 at our institution. 1081 (60%) pts achieved CR. Among them, 266 (25%; 15% of all treated) maintained 1^st CR for at least 3 years. The 1^st 200 pts are described in this analysis: 33 after ASCT and 167 after chemotherapy (chemo) alone. Median time to CR from initiation of induction chemotherapy was 34 days (range, 19-115) for pts who received ASCT and 28 days (17-104) for chemo only. Characteristics of AML survivor pts at time of diagnosis were as follows: hypertension (HTN) was present in 25% of the pts; cardiac disease in 7%; hypothyroidism in 5%; diabetes (DM) in 7%; depression in 6%; osteoporosis in 2%; chronic obstructive disease (COPD) or asthma in 4%. Median number of medications per pt at baseline was 1 (0-7). Relapses after maintaining CR for ≥3 years (i.e., late relapses) were noted in 12% of the pts: 9% of the pts treated with ASCT and 12% of pts with chemo alone. The median CR duration for those who relapsed was 4 years (3-10) and 4.8 years (3-12), respectively. At relapse, karyotype was different from the karyotype at the time of diagnosis in 47% of the cases: 100% after ASCT and 41% after chemo alone. Mutational status changes at relapse were noted in 31% of the pts. New Flt3 ITD mutations were the most common change, noted in 75% of pts who had a mutational status change. A 2^nd complete remission (CR2) was achieved in 52% of pts, including 33% of pts that had received ASCT and 56% of pts treated with chemo alone. The median CR2 duration was 5 months and 10 months (3-30) respectively. The median survival after relapse was 13 months (1 to 42). Four pts with relapsed disease who initially were treated with chemo only underwent ASCT; no patient received a 2^nd ASCT. New medical problems that were present at the 3 year mark included: HTN in 10% of pts; cardiac disease in 4%; hypothyroidism in 4%; depression in 4%; renal insufficiency in 3%; pulmonary disease in 2%; DM in 3%; hematological disorders, including anemia, thrombocytopenia, monoclonal gammopathy of undetermined signigicance (MGUS), systemic mastocytosis & Waldenstorm’s macroglobulinemia, in 5%. Pulmonary disorders (e.g., bronchiolitis obliterans and COPD) occurred in 6% of pts who underwent ASCT and 2% of pts who treated with chemo alone. Renal insufficiency was noted in 9% of pts who underwent ASCT and in 2% of pts treated with chemo alone. The median number of medication per pt 3 yrs from initial CR was 3 (range, 0-11). New medical problems that developed at time of last follow up included: HTN in 12% of pts, cardiac disease in 6%, hypothyroidism in 5%, depression in 7%, renal insufficiency in 4%, pulmonary disease in 3%, DM in 5%, hematological disorders in 6%. Cardiac problems, including the development of coronary artery disease, myocardial infarction, congestive heart failure and arrhythmias were noted in 3% of pts who underwent ASCT and in 6% of pts treated with chemo alone. The median number of medications per pt at last follow up was 3 (0-14). Second malignancies occurred in 10% of pts. The most common 2^nd malignancies were colorectal carcinoma, breast cancer, prostate cancer and lymphoma, each occurring in 2% of pts. At median follow up of 4.2 years (3.2-10.2) and 4.9 years (3.2-12) respectively, 94% and 80% of pts are alive. In descending order, the most common causes of death included AML relapse, second malignancy and myocardial infarction.

AML pts who achieved CR for at least 3 years have a low incidence of late relapses. New medical problems including heart disease and second malignancies may occur but most pts are still currently alive. AML pts who maintain 1^st CR for at least 3 years require ongoing medical care and long-term surveillance.

No relevant conflicts of interest to declare.