Poster Session I: Acute lymphoblastic leukemia - Clinical
Acute lymphoblastic leukemia (ALL) in adults is associated with poor outcomes with long-term overall survival (OS) of 40%. ALL is more frequent in children, where comorbidity is infrequent. Currently, Hispanic population is characterized by an increasing adult comorbid population. The above, in addition to the high prevalence of ALL in adults, raises the need of knowing the prevalence and impact of comorbidity in adult ALL.
Analyze the impact of comorbidity on OS of adult patients with ALL.
Retrospective study that included >18 year-old patients with diagnosis of ALL treated and followed between January 2009 and September 2016 at our institution. To evaluate comorbidity, the hematopoietic cell transplant comorbidity index (HCT-CI) and the Charlson comorbidity index (CCI) were used.
We included 176 patients. The adolescent and young adult (AYA) groups represented the 64.8% of the cohort, the additional 35.2% was represented by adults ≥40 year-old.
The most frequent comorbidities were overweight and obesity in 54.4% (AYA 45.6% vs. adults 71.0%; p = 0.001) and type 2 diabetes mellitus in 10.4% (AYA 1.8% vs. adults 25.8%; p < 0.001). Regarding comorbidity scores, 29.1% had HCT-CI ≥3 (AYA 23.7% vs. adults 39.3%; p = 0.037) and 47.4% a CCI≥1 (AYA 32.7% vs. adults 74.2%; p < 0.001).
The induction related mortality rate was 13.6% (AYA 10.5% vs. adults 19.4%, p = 0.113). Independent risk factors at diagnosis related to induction mortality were: total bilirubin >1 g/dL (OR 3.96, 95% CI 1.19-7.37; p = 0.02) and albumin <3.5 g/dL (OR 3.06, 95% CI 1.20-7.82; p = 0.02).
The OS was significantly longer in the AYA group when compared to the group of adults >40 years-old with median OS of 13.8 and 8.0 months respectively (p < 0.001). Patients with lower HCT-CI scores (HCT-CI<3 vs. HCT-CI≥3) and lower CCI (CCI<1 vs. CCI≥) were significantly associated with a better OS survival (HCT-CI OS 13.1 vs. 7.6 months; p = 0.005 and CCI OS 13.2 vs. 10.1 months, p = 0.003). Interestingly, this impact of comorbidity scores over OS, remained significant in the group of adult patients (HCT-CI OS 10.8 vs. 4.3 months, p = 0.003 and CCI OS 11.2 vs. 6.7 months; p = 0.044) but not in the AYA group (HCT-CI OS 14.4 vs. 12.0 months; p = 0.307 and CCI OS 13.7 vs. 14.4 months, p = 0.471). On multivariate analysis, HCT-CI ≥3 (HR 1.59, 95% CI 1.06-2.39, p = 0.026), age >40 years (HR 1.69, 95% CI 1.14-2.51, p = 0.009), and achievement of complete remission with the first induction chemotherapy regimen (HR: 0.317, 95% CI 0.217-0.462, p>0.001) were independent prognostic factor for OS.
There are no previous reports analyzing the impact of comorbidities in adults with ALL. This study shows that both HCT-CI≥3 and CCI ≥1 are associated with poor outcomes in adults ≥ 40 years. The high prevalence of overweight/obesity and diabetes in our patients urges the need for an objective assessment of comorbidities at diagnosis.