Journal of Cancer Therapy, 2013, 4, 1321-1329
http://dx.doi.org/10.4236/jct.2013.48156 Published Online October 2013 (http://www.scirp.org/journal/jct)
1321
The Unmet Need in Chronic Lymphocytic Leukemia:
Impact of Comorbidity Burden on Treatment
Patterns and Outcomes in Elderly Patients
*
Sacha Satram-Hoang
1#
, Carolina Reyes
2,3
, Khang Q. Hoang
1
, Faiyaz Momin
1
, Sandra Skettino
2
1
Q. D. Research, Inc., Granite Bay, USA;
2
Genentech, Inc., South San Francisco, USA;
3
University of California San Francisco, San
Francisco, USA.
Email:
#
sacha@qdresearch.com
Received September 18
th
, 2013; revised October 15
th
, 2013; accepted October 22
nd
, 2013
Copyright © 2013 Sacha Satram-Hoang et al. This is an open access article distributed under the Creative Commons Attribution
License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
ABSTRACT
Introduction: Chronic lymphocytic leukemia (CLL) is a disease of the elderly. Elderly patients often have increased
comorbidity burden and loss of organ reserve that may impact their ability to tolerate cancer therapy. We described real-
world characteristics of typical CLL patients and identified factors predictive of receiving treatment. Methods: A ret-
rospective cohort analysis of 8343 first primary CLL patients was performed using the linked Surveillance, Epidemiol-
ogy, and End Results-Medicare database. Patients were diagnosed from 1/1/1998 to 12/31/2007, >66 years, and con-
tinuously enrolled in Medicare Parts A and B in the year prior to diagnosis. Comorbidity was examined using the Na-
tional Cancer Institute comorbidity index and the Cumulative Illness Rating Scale. Cox and Logistic regression model-
ing assessed patient characteristics predictive of receiving treatment within the first year after diagnosis. Results: Me-
dian follow-up time from diagnosis was 782 days. During the study time period, there were 3366 (40%) treated patients
and 4977 (60%) untreated. Even among those diagnosed with advanced stage (n = 4213), 57% were not treated. Treated
patients were younger at diagnosis compared to untreated (76 vs. 79; p < 0.0001). In general, as age increased, the inci-
dence and severity of comorbidities increased. In multivariate regression analyses, the treatment rate was significantly
lower among patients >80 years, females, and with early stage disease; and significantly decreased with increasing co-
morbidity burden. Conclusions: Age, gender, comorbidity and stage were predictive of receiving treatment. Among
patients with advanced stage, 57% were not being treated possibly due to older age and/or higher comorbidity burden.
Keywords: Chronic Lymphocytic Leukemia; Elderly Patients; Comorbidities; Treatment; Survival
1. Introduction
Chronic lymphocytic leukemia (CLL) is the most com-
mon type of leukemia diagnosed in older adults [1-3],
with 68% of new cases diagnosed in individuals 65 years
or older and median age at diagnosis of 72 years [3,4].
Elderly patients are frequently compromised by concur-
rent pathologic conditions and/or physiological decline
of major organ systems; little is known about the spec-
trum or frequency of comorbidities in CLL patients. Loss
of organ reserve and the comorbidities associated with
aging are considered important determinants of patients’
ability to tolerate the side effects of cancer therapy [5].
However, the majority of CLL clinical trials primarily
enroll younger patients who are otherwise in good health
and are better able to tolerate treatment-related adverse
events [6-9], and this makes optimal treatment strategies
and disease management unclear for typical patients.
Both age and comorbidities are significantly associ-
ated with the prognosis of patients with CLL, with older
age being one of the most significant predictors of over-
all survival [6,10]. Fludarabine, cyclophosphamide, and
rituximab (FCR) is considered the gold standard first-line
treatment for physically fit CLL patients [6,11], but those
with comorbid conditions may receive alternative thera-
pies or a chemotherapy dose reduction in the FCR regi-
men [12-14].
*
Funding Source: This study was funded by Genentech, Inc. through a
contract with Q.D. Research, Inc.
Financial Disclosure: Dr. Satram-Hoang, Dr. Hoang, and Mr. Momin
work for Q.D. Research, Inc. in a research and consulting capacity. Dr.
Reyes and Dr. Skettino are employees and shareholders of Genentech
Inc.
#
Corresponding author.
Copyright © 2013 SciRes. JCT