Differentiated thyroid cancer survival, recurrence rates by disease stage and quality of life in the Northern Cancer Network
Simon Pearce, Professor of Endocrinology and Honorary Consultant Endocrinologist, Institute of Genetic Medicine, International Centre for Life, Newcastle upon Tyne
Thyroid cancer causes about 2,500 deaths in the UK every year. International statistics show that the UK has a higher death rate compared to many other European countries. It is unclear why that might be the case, especially since a lot of NHS resources have been allocated to cancer care over the past 20 years. One possible explanation is that very small thyroid cancers (which rarely cause death) are not recorded in UK national statistics. This study will look at death statistics from thyroid cancer with relation to how advanced the cancer was when it was diagnosed. Such information will make it possible to compare with other countries in a more informative and fair way, so that we can understand why there are differences. This is important in planning and improving services for patients with thyroid cancer. Besides surviving from cancer, the quality of life of thyroid cancer patients is important. This study will also find out about quality of life of survivors of thyroid cancer 5 and 10 years after they have been diagnosed. Correlating quality of life measurements with other aspects of the cancer (for example how advanced it was when diagnosed and with some of the treatments) will give us a better understanding of how to treat patients with thyroid cancer in future.
Interim report February 2017
So far we have ascertained disease status and 10 year survival in 47 patients. There were 21 patients with stage I disease, 15 with stage II, 1 with stage III, 4 with stage IVA and 1 with stage IVC.
Ten year survival
Forty-three out of 47 patients survived 10 years after diagnosis. Three of these deaths were unrelated to thyroid cancer The single death from thyroid cancer was aged 50 at the time of diagnosis, female and had stage IVA disease with papillary thyroid cancer and tall cell elements. She died of pulmonary and cerebral metastases. So the overall disease specific 10 year survival was 98%.
Recurrences were noted in three patients, one with stage I, and 2 with stage IVA disease. Excluding patients who died, the overall recurrence rate was 6.9% at 10 years.
Four patients who survived 10 years had another cancer diagnosis. Three developed it after the diagnosis of thyroid cancer (two breast, one lymphoma) and one had been treated for acute lymphocytic leukaemia three years before the diagnosis of thyroid cancer.
These figures are very preliminary and represent a small number treated in our centre. As expected the majority of cases had low risk thyroid cancer (44.7% had stage I disease). However, so far the disease-specific 10 year mortality is extremely low at 2% and in contrast to the high mortality quoted by Eurocare-4 (a Europe-wide database on cancer survival) for England (19.5% five year mortality compared to other European countries e.g. Iceland 96%). One possible explanation for this discrepancy is that the Eurocare-4 data did not report survival based on disease stage, and it is probable that the UK registered data are heavily biased towards advanced thyroid cancers.
Progress has been slow due to the lengthy procedures that need to be observed in obtaining data from the National Cancer Intelligence Network, but so far the data are encouraging and at least this is proof that it is possible to collect such data.