Abstract

Epidemiological information on chronic myeloproliferative disorders (CMPD), notably Philadelphia (Ph) and/or bcr/abl positive chronic myeloid leukemia (CML), is rare. National cancer registries and clinical trials differ with regard to median age of CML patients by 10 to 20 years (Table). Therefore, an evaluation was conducted in a defined area in Germany between 1998 and 2000 to determine incidences and compare clinical characteristics of Ph and/or bcr/abl positive CML patients participating and not participating in trials. 68 (37.4%) hospitals and 241 specialty practices (16.4%) reported 893 newly diagnosed CMPD patients. CML patients represented 24.9% of all cases with CMPD. The crude incidence of CML cases (n=218) was 0.79, that of the 172 Ph and/or bcr/abl positive CML cases 0.62 and that of CMML (n=61) 0.22. The incidence of CML and CMML cases combined was 1.01. 110 (64.0%) of the 172 Ph and/or bcr/abl positive CML patients participated in clinical studies, mainly CML Studies III and IIIA of the German CML Study Group. Median age was significantly different between patients participating and not participating in clinical trials: (54.1 vs. 64.8 years, p=0.0001). The chance for a Ph and/or bcr/abl positive CML patient < 65 years to be enrolled in a clinical study was 3.8 times higher than for a CML patient ≥ 65 years (OR=3.8, CI: 1.9–7.3). Male patients had a slightly higher probability to be enrolled in a study than females (OR=1.5 (CI: 0.8–2.8)). Our data indicate that 36% of the Ph and/or bcr/abl positive CML patients registered in a defined area of Germany are not treated in clinical trials, that elderly patients have a lower probability to be included in trials than younger patients and that patients participating in trials are 10.7 years younger than those who do not.

Age of CML Patients in Population based Registries and in Clinical Trials

A) RegistriesAge mean (years ± S.D.) /
Thames Cancer Registry, U.K. 65 (20–98) 
SEER Cancer Statistics Review, 1975–2004 68 (range not available) 
SEER cancer statistics review, 1973–1998 64 (range not available) 
B) Trials  
The Italian Cooperative Study Group on Chronic Myeloid Leukemia. N Engl J Med 1994 48 ± 14 
Hehlmann et al., Blood 1994 48 (17–85) 
Guilhot et al., N Engl J Med 1997 50 (7–70) 
Hasford et al., JNCI 1998 49 (10–85) 
The Benelux CML Study Group. Blood 1998 56 (20–83) 
Baccarani et al., Blood 2002 45 ± 13 
Hehlmann et al., Leukemia 2003 48 (10–83) 
O’Brien et al., N Engl J Med 2003 50 (18–70) 
Hehlmann et al., Blood 2007 49 (11–90) 
A) RegistriesAge mean (years ± S.D.) /
Thames Cancer Registry, U.K. 65 (20–98) 
SEER Cancer Statistics Review, 1975–2004 68 (range not available) 
SEER cancer statistics review, 1973–1998 64 (range not available) 
B) Trials  
The Italian Cooperative Study Group on Chronic Myeloid Leukemia. N Engl J Med 1994 48 ± 14 
Hehlmann et al., Blood 1994 48 (17–85) 
Guilhot et al., N Engl J Med 1997 50 (7–70) 
Hasford et al., JNCI 1998 49 (10–85) 
The Benelux CML Study Group. Blood 1998 56 (20–83) 
Baccarani et al., Blood 2002 45 ± 13 
Hehlmann et al., Leukemia 2003 48 (10–83) 
O’Brien et al., N Engl J Med 2003 50 (18–70) 
Hehlmann et al., Blood 2007 49 (11–90) 

Author notes

Disclosure: No relevant conflicts of interest to declare.