Table 2: Tumour Data Items

Item	Description
[INCIDENT DATE]	The incident date is the day, month and year the tumour was first diagnosed, whether clinically or microscopically confirmed. It is the date when the cancer was confirmed by the best of the diagnostic tests performed. Incident date is the base for calculating incidence rates, outcome and survival. The date field is in a format of DDMMYYYY.
[BASIS OF DIAGNOSIS]	This field records the eligibility of the tumour for registration and allows derivation of the degree of certainty of diagnosis. Basis of diagnosis records the best method used to confirm the presence of the cancer being reported. It is therefore an indicator of data quality, with microscopic histological verification being viewed as the ‘gold standard’ for diagnosis. The suggested codes are hierarchal, so that the higher number represents the more valid basis and should thus be used for this purpose. This permits calculation of the number of notifications per case, number of sources per case, and the number of death certificate notifications.
[TOPOGRAPHY]	Topography is the detailed primary site of the body where the cancer originated. It is the most important item of data collection. Four-digit ICD-O (3) coding is used and can be referred from the appendices of the ICD-O (3) manual.
[MORPHOLOGY]	The cell type(s) of the malignant disease. Although the topography of the primary tumour is essential, the morphology is an index of the confidence of the diagnosis. The morphology is related to the prognosis and is used to determine the incidence of tumours of different histology and behaviour for epidemiological analysis.
[BEHAVIOUR]	Behaviour is how the tumour behaves. Most benign neoplasms are not life threatening and not registrable. If morphology is coded using ICD-O the fifth digit of the morphology code expresses the behaviour of the tumour. There are certain identifiable stages in the growth of a malignant neoplasm which are represented by behaviour codes. The stage of development of the tumour at the time of diagnosis reflects its clinical behaviour and it is therefore extremely important in establishing the likely prognosis for the patient.
[GRADE]	Grade is how aggressive the tumour is – a measure of how far the tumour is likely to spread. Pathologic testing determines the grade or degree of differentiation of the tumour.
[STAGE]	Stage is how far the tumour has grown and infiltrated other tissues at the time of diagnosis. SEER Summary stage is used as a shorthand or notation to describe the extent of disease. Stage at first diagnosis of the tumour is used to determine treatment, estimate prognosis, to plan and evaluate cancer screening and prevention programs, standardise groupings, and to evaluate and compare results.
[TNM STAGING]	This is the international staging classification published and maintained by the International Union Against Cancer (UICC). The UICC TNM classification used to describe the stage of the tumour and should only be recorded if it is given in the clinical notes or pathology report.