research
Prognostic Models in Head and Neck Oncology: Predictors and dynamics
- Publication date
- 19 October 2011
- Publisher
- Head and neck malignancies originating from the mucosal lining of the upper aerodigestive
tract (head and neck squamous cell carcinoma’s: HNSCC’s) and the salivary glands
make up nearly 5% of the total number of malignant tumours in the Netherlands. Variation
of incidence trends between sites exist1, the general incidence of HNSCC’s is 17/100,000;
the incidence of malignant salivary gland tumours 0.7/100,000 (Netherlands Cancer
Registry). In this thesis we discuss prognostics in both types of cancer, although we focus
on HNSCC’s. Once diagnosed with head and neck cancer, the prognosis (likely outcome of
the disease) plays an enormous role in choosing treatment options and informing patients.
Generally, survival rates for patients vary depending on the type and the stage (extent) of
the cancer involved. The fi ve-years survival rate of patients (the percentage of patients
who survive at least fi ve years after the cancer is detected) with HNSCC is around 50%.
For those with salivary gland cancer this fi gure is highly dependent on the type of tumour
and diff ers between 30% to nearly 100%. The prognosis at the time of diagnosis of cancer
is taken into account in the choice of treatment. When it comes to informing patients
about their prognosis, physicians also incorporate events such as staying free for cancer
or the occurrence of a non related health event (eg. myocardial infarction) during follow
up. The methods of determination of prognosis, the way prognosis changes over time
and the way in which prognosis should be discussed with patients are the central themes
of this thesis. This introduction aims to explore the concept of prognosis, the fallibility of
prognostic factors, the statistical methods used when working with prognostic factors
and the role prognosis plays in the process of decision-making. Finally, we will state the
central hypotheses for this thesis.