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Research on diagnosing brain tumours

Children and young adults in the UK experience, on average, a longer time between the onset of symptoms and diagnosis (symptom interval) of a brain tumour than their counterparts in many other countries. A prolonged symptom interval is associated with increased long term disability due to irreversible neurological damage, and significant patient and family/carer distress.

Symptom interval

In the UK the median time from symptom onset to diagnosis of a brain tumour in a child is 12-13 weeks. Half of children and young adults therefore take over 3 months to reach a diagnosis.

A systematic review shows this symptom interval is up to three times longer than that for children in other countries including the USA. Furthermore, there was no significant improvement in symptom interval between the two data collection periods (1987 - 2001 and 2004 - 2006) (Ref 1; Ref 2).

Many children present repeatedly to healthcare professionals with symptoms and signs known to be associated with brain and spinal tumours.

Effects of prolonged symptom interval

Delayed diagnosis of childhood brain tumours often results in an emergency presentation when children are extremely unwell. The risk of peri-operative morbidity is increased in children who present as an emergency. In the longer term, a prolonged symptom interval is associated with increased cognitive deficits, endocrinopathies and visual loss.

Children and young people with brain tumours develop increasing numbers of symptoms and signs during the interval from symptom onset to diagnosis. The table below shows the increase in symptom and sign complexes between symptom onset and diagnosis experienced by the children and young people recruited to the cohort study.

Symptomatology At onset At diagnosis
Visual system 17% 70%
Motor abnormality 22% 67%
Cranial nerve palsies 17%
54%
Behavioural change
3%
40%
Nausea and Vomiting
28%
63%
Headache
40%
58%
Endocrine / Growth
7%
25%

Table 1: Increase in proportion of patients displaying specific signs and symptoms over symptom interval between onset and diagnosis in rank order of percentage increase (top 7 symptoms).

The development of additional symptoms and signs during the symptom interval reflects progressive neurological damage due to either the direct effects of the tumour on the brain or raised intracranial pressure. Many children with brain tumours have life-long visual impairment, cognitive deficits and endocrinopathies (due to hypothalamic and pituitary damage). Reducing the symptom interval experienced by children diagnosed with a brain tumour should reduce the long term disability they experience.

The prolonged symptom interval prior to diagnosis can also have a significant psychological impact on those families that are affected. Many families present repeatedly to healthcare professionals and feel that they have had to insist that something was wrong with their child / young person for a diagnosis to be made. Families find this extremely distressing, and often say that they felt regarded as "time wasters" and "neurotic parents" (Ref 4).

References

Wilne SC, Collier J, Kennedy C, Koller K, Grundy R, Walker D. Presentation of childhood CNS tumours: a systematic review and meta-analysis Lancet Oncol. 2007 Aug;8(8):685-95.

Wilne SC, Kennedy C, Jenkins A,.Grout J,.Mackie S,Koller K, Grundy R, Walker D. Progression from first symptom to diagnosis in childhood brain tumours: a multicentre study (Abstract). Archives of Disease in Childhood. 2007;92 (Supp 1):A69

Wilne SC, Koller K, Collier J, Kennedy C, Grundy R, Walker D. The diagnosis of brain tumours in children: a guideline to assist healthcare professionals in the assessment of children who may have a brain tumour.

Arch Dis Child. 2010 Jul;95(7):534-9. Epub 2010 Apr 6. Dixon-Woods M, Findlay M, Young B, Cox H, Heney D. Parents' accounts of obtaining a diagnosis of childhood cancer. Lancet. 2001;357(9257):670-4.