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· DOS Abstracts
Excess mortality in soft tissue sarcoma patients:
a Danish population-based study
Katja Maretty-Nielsen, Ninna Aggerholm-Pedersen, Johnny Keller, Akmal
Safwat, Steen Baerentzen, Alma Pedersen
Department of Experimental Clinical Oncology, Aarhus University Hospital;
Department of Orthopaedic Surgery, Aarhus University Hospital; Department
of Oncology, Aarhus University Hospital; Department of Pathology, Aarhus
University Hospital; Department of Clinical Epidemiology, Aarhus University
Hospital
Background:
To assess the excess mortality caused by soft tissue sarcoma
(STS), sarcoma-specific estimates are often reported; however, these rely on
precise and correct data on the cause of death, which can be difficult to acquire.
Another, more precise, method is to assess the relative mortality, i.e., mortality
in sarcoma patients compared to the general population.
Purpose / Aim of Study:
The aims of this study were to assess the relative
mortality in STS patients, and to compare this with the sarcoma-specific mor-
tality.
Materials and Methods:
We included 1246 patients treated for STS at the
Aarhus Sarcoma Centre between 1979 and 2008, and 6230 individually age-
and sex-matched individuals from the general population. The relative mortality
was estimated as rates and rate ratios, using the Cox proportional hazard model.
The sarcoma-specific mortality was compared to the corresponding relative
mortality.
Findings / Results:
The overall 5- and 10-year relative mortality was 32.8%
and 36.0% Overall, STS patients had a 4.4 times higher risk of dying within the
first five years after diagnosis and a 1.6 times higher risk between five and ten
years compared with the general comparison cohort. Patients with low-grade
STS did not have increased mortality compared with the general population. The
relative mortality was highest in younger patients and in patients without co-
morbidity. The overall 5- year sarcoma-specific mortality was underestimated
by 3.1 percentage points compared to the relative mortality.
Conclusions:
Patients with low-grade STS did not have increased mortality
compared with the general population. A tendency towards underestimating
mortality due to STS was seen when sarcoma-specific mortality using death
certificates was reported.
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