Factors influencing survival from melanoma in England, Northern Ireland and Scotland

Melanoma is amongst the top ten most common cancers in the UK, and is associated with higher mortality than other skin cancers. In 2010, around 12,800 people in the UK were diagnosed with melanoma, and around 2,200 people died from it (United Kingdom Cancer Information Service (UKCIS)).

Given the large numbers of people diagnosed with melanomas, it is important to understand what influences someone’s chances of survival once they have been diagnosed. This can help us to focus on interventions or targeted campaigns that are likely to maximise improvements in survival. This report explores the impact of various factors (sex, age, tumour thickness, anatomical location, morphology, ethnicity, and income deprivation) on the chances of surviving for five years after being diagnosed with melanoma in England, Northern Ireland, and Scotland.

Information about the cohort of patients to be used in the survival analysis (Table 1) was extracted from the Celtic National Cancer Data Repository 2010 (Celtic NCDR 2010), and includes those patients with a first primary diagnosis of melanoma (ICD-10 Code: C43) in England, Northern Ireland, and Scotland, in the years 2002 to 2010.
Relative five-year survival was used for the analysis and estimated separately within each country for sub-groups of the overall cohort, categorised according to the factors of interest: sex, age, tumour thickness, anatomical location, morphology. Some data limitations were experienced due to differences in registering and reporting the data between England, Northern Ireland and Scotland. Although requested to take part, Wales felt that their data was not suited for such a project.

The main results were as follows:
• men had significantly poorer five-year relative survival than women in all three countries and overall those aged 60+ in England and Scotland had a significantly worse five-year survival than those aged below 60. This was not the case in Northern Ireland
• the thickest tumours were more common among older males, and had a greater tendency to be on the head and neck, of nodular morphology and overall the five-year survival was poorer
• Northern Ireland had the worst five-year survival for tumours thicker than 4mm, although not significantly lower that Scotland
• across all three countries five-year survival was poorer for head and neck, and trunk tumours, compared to those on the limbs – patients with a tumour of unspecified anatomical site had significantly better survival in Northern Ireland; it seems that the recording of this category may differ across the countries 5
Factors influencing five-year survival from melanoma in England, Scotland, and Northern Ireland
• nodular melanomas were associated with a poorer prognosis compared to lentigo and superficial spreading melanomas across the three countries
• five-year survival was poorer in more deprived areas in England, even when controlling for the effect of deprivation on mortality in the background population; data for Northern Ireland and Scotland was not available
The impact of various factors on the five-year relative survival from melanoma was broadly the same between countries, making the findings robust, although a lack of power (particularly due to smaller cohorts in Scotland and Northern Ireland) sometimes prevented effects from being detected.