The latest report of the National Cancer Registry summarizes incidence, mortality, survival and treatment for cancer in Ireland during 1994-2012, focusing particularly on 2010-2012. Findings highlighted in the report include ongoing increases in the incidence of many cancers but, in general, improvements in treatment, early detection and survival and corresponding reductions in mortality rates. Less favourable findings include ongoing increases in lung cancer incidence and mortality among Irish women, high mortality from pancreatic cancer (the fifth most common cause of cancer death in Ireland), and low treatment rates for elderly patients.
Incidence: new cases per year and stage at diagnosis
In the most recent three years for which full data are available (2010-2012), on average about 36,000 newly diagnosed tumours were registered per year. Of these cases, just over 20,000 involved invasive cancers other than the less serious, non-melanoma skin cancers. Over half involved the four most common major malignancies – prostate (3,400 cases per year), breast (2,800), colorectal (2,500) and lung cancer (2,300).
Age-standardised incidence rates of cancer in Ireland in 2012 were estimated to be 10% higher than the European Union average for males, and 16% higher than the EU average for females. This included higher Irish rates of colorectal, female lung, breast and, especially, prostate cancer, although male lung cancer rates were lower in Ireland.
Time-trends in cancer incidence since 1994 have varied substantially depending on the cancer type. Overall, age-standardised incidence rates for invasive cancers have increased by about 1% per year in both males and females (throughout 1994-2012). Many individual cancer types have also shown upward trends in annual rates, for example lymphomas and prostate, melanoma , kidney, thyroid, cervical, uterine and female lung cancers, although the likely factors involved may differ (e.g., screening, lifestyle factors or diagnostic improvements). But some cancers have shown declines in incidence rates, notably stomach cancer and male lung cancer.
For some cancers, there has been a marked shift towards earlier stages at diagnosis – notably for melanoma and for breast, prostate, kidney and thyroid cancers – reflecting improvements in early detection.
Mortality: deaths from cancer
Cancer remains the second most common cause of death in Ireland, after diseases of the circulatory system. Deaths from cancer averaged about 8,800 deaths per year during 2010-2012, representing about 30% of all deaths in that period. Age-standardised rates of cancer mortality were about 37% higher in men than in women. Lung cancer was by far the single most common cause of cancer death during 2010-2012, with approximately 1,800 deaths annually, with deaths from colorectal (990), breast (680), prostate (550) and pancreatic cancer (490) the next most common.
Compared with the EU as a whole, estimated cancer mortality rates in Ireland in 2012 were 14% higher for Irish women but were 9% lower for Irish men. For women, lung cancer mortality for Ireland was substantially (34%) higher than the EU average.
Unlike incidence, time-trends in cancer mortality rates have fallen overall throughout 1994-2012, by about 1.5% per year in men and about 1.1% per year in women. But, like incidence, the trends have varied by cancer type, although many cancer types have shown ongoing reductions in mortality rates since the early 1990s. The exceptions, showing significant increases in rates, include melanoma in both sexes and lung and uterine cancer in women.
Trends in cancer mortality reflect changes in both cancer incidence and survival. Survival estimates for most cancer types in Ireland have improved over time, although the trend is clearer for some cancers than for others. Some of the more striking improvements have been seen for colorectal, breast, kidney, testicular and prostate cancers and for multiple myeloma, lymphoma and leukaemia. However, across ten major cancer types the recently published CONCORD-2 study indicated that, in general, Ireland remained approximately mid-way in the ranking of survival estimates among European countries.
As average survival improves, as incidence (or diagnosis) of many cancers increases, and the population ages, cancer prevalence - the number of cancer survivors - in Ireland continues to grow. Of all the patients diagnosed with invasive cancer during 1994-2012 (excluding non-melanoma skin cancer), approximately 122,500 were still alive at the end of 2012. Of these, almost 94,000 had survived ten years or more since their diagnosis. The growing population of cancer survivors has implications for health service provision in the decades ahead.
The survival improvements seen for some cancers reflect, in part, detection at earlier stages than in earlier years. For the majority of cancers, however, improvements in treatment are probably the major contributor to survival improvements. Most notably, the use of chemotherapy, either on its own or more frequently in combination with other treatment modalities, has increased markedly across the majority of relevant cancer types. Radiotherapy use has also increased across many cancer types, and the proportion of patients having surgical treatment has increased for some cancers. These improvements mean that the overall proportion of cancer patients having tumour-directed treatment (as opposed to treatments aimed at symptom relief and palliation) continues to increase. However, the proportion of older patients (≥65 years) having no tumour-directed treatment remains high.