Cancer in children is rare, and most of the symptoms below have a simple cause such as an infection; but if they are persistent, keep coming back or have no clear cause, they should be checked: a long-lasting fever, paleness and tiredness, easy bruising or bleeding, bone pain or limping, a lump or swelling in the abdomen, neck or elsewhere, a white pupil (instead of red, in a flash photo), morning headaches or headaches that get better after vomiting, new problems with walking and balance, and unexplained weight loss [1, 2, 8, 9]. If your child has seen a doctor several times with the same symptoms, or you as a parent feel something is not right, ask for further tests [2, 3]. Most childhood cancers can be cured if they are diagnosed early and fully treated at an experienced centre [1].
Key points
- Cancer in children is rare and most of these symptoms have a simple cause; what matters is a symptom that persists, keeps coming back, or several symptoms together [3, 4].
- The commonest cancers in children are leukaemia (blood cancer), brain tumours and lymphoma [1, 10].
- A white pupil in a flash photo or a new squint may be a sign of eye cancer (retinoblastoma); see an eye doctor promptly [7, 8].
- Morning headaches or headaches that get better after vomiting, especially with new problems with walking, balance or vision, should be checked promptly [5, 9].
- Most childhood cancers are curable: where full treatment is available, more than 8 in every 10 children are cured, and late diagnosis is one of the main reasons children are lost [1].
Warning signs of cancer in children
| Symptom | What it may be a sign of | What to do |
|---|---|---|
| Persistent paleness and tiredness | Anaemia caused by leukaemia [2, 4] | A full blood count (CBC) within 1 to 2 days [2] |
| Unexplained fever or one infection after another | Leukaemia [2, 4] | If there is no clear cause, a CBC [2] |
| Bruising, bleeding or tiny red spots under the skin | A shortage of platelets in leukaemia [2, 4] | Unexplained tiny red spots: see a doctor the same day [2] |
| Bone or joint pain, limping | Leukaemia or a bone tumour [2, 4] | Persistent or unexplained pain: an examination, a blood test and an X-ray [2] |
| A lump in the abdomen or a swollen abdomen | Neuroblastoma or a kidney tumour (Wilms tumour); an enlarged liver and spleen in leukaemia [2, 4] | See a doctor within 1 to 2 days [2] |
| A swollen gland or lump in the neck, armpit or elsewhere | Lymphoma or a soft tissue tumour (sarcoma) [2] | An unexplained gland or a lump that is getting bigger: rapid assessment [2] |
| A white pupil or a new squint | Retinoblastoma (cancer of the retina) [7, 8] | An eye doctor's examination without delay [2] |
| Morning headaches or headaches that get better after vomiting | A brain tumour, especially with repeated nausea and vomiting [5, 9] | See a doctor as soon as possible |
| New problems with walking, balance, vision or behaviour | A brain tumour [2, 5, 9] | See a doctor within 1 to 2 days [2] |
| A growing head size in a baby | A brain tumour in children under 4 [5] | A doctor's examination |
| Blood in the urine | A kidney tumour (Wilms tumour) [2] | See a doctor within 1 to 2 days [2] |
| Unexplained weight loss | Many cancers [1, 4] | See a doctor to find the cause |
Most of these symptoms in children have simple causes such as infections; this table does not replace an examination by a doctor. If a symptom persists, keeps coming back or you are worried, go back to the doctor [2, 3].
Which cancer, which signs?
Leukaemia (blood cancer)
The commonest cancer in children. More than half of affected children have an enlarged liver or spleen, paleness, fever or bruising; arm and leg pain and limping are also common [4]. Read more: symptoms of leukaemia.
Brain tumours
The commonest symptoms are headache, nausea and vomiting, and problems with walking and coordination [5]; a morning headache or a headache that gets better after vomiting is important [9]. In children under 4, a growing head, irritability and lethargy are seen. More than half of children have no signs of raised pressure inside the head, so take any new nervous system problem seriously [5]. Read more: symptoms of a brain tumour and brain tumours.
Lymphoma
More common in teenagers [1]. Unexplained swollen lymph nodes in the neck or elsewhere, sometimes with fever, night sweats, breathlessness, itching or weight loss [2]. Read more: symptoms of lymphoma.
Retinoblastoma (eye cancer)
The commonest sign is a white pupil, followed by a squint [7]; a white pupil may be seen in flash photographs [8]. In a national cancer registry from Iran, almost all affected children were alive 5 years later [10], but in low-income countries where it is diagnosed late, nearly half of the children had disease that had spread beyond the eye at diagnosis [7].
Neuroblastoma and Wilms tumour
A lump or swelling of the abdomen in young children; in Wilms tumour (a kidney tumour) there is sometimes blood in the urine [2].
Bone and soft tissue tumours
Bone pain or swelling that has no clear cause or keeps going, and a lump that is getting bigger [2].
The path to diagnosis
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Blood tests
A full blood count (CBC) is the simplest test for leukaemia, and in a child with unexplained paleness, fever, bruising or bone pain it should be done within 1 to 2 days [2].
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Referral to a specialist children's cancer centre
If cancer is likely, the child is referred to a specialist children's centre for a biopsy and treatment; an accurate diagnosis is essential to choose the right treatment [1].
When should I call my doctor?
See a doctor or go to an emergency department the same day if your child has tiny red or purple spots under the skin with no clear cause [2], or a severe headache with repeated vomiting, unusual drowsiness, a seizure or sudden weakness of an arm or leg.
See a doctor within a few days if your child has paleness and tiredness, an unexplained fever, a lot of bruises, bone pain or a limp that keeps going, an unexplained lump or swollen gland, a swollen abdomen, a white pupil or a new squint, or morning headaches [2, 8, 9].
If you have seen a doctor several times with the same symptoms or you are still worried, go back and ask for further tests; medical guidelines say that parents' concern should be taken seriously [2, 3].
One important step: early, complete treatment at an experienced centre
Most childhood cancers can be cured with widely used medicines, surgery and radiotherapy [1]. Where full treatment is available, more than 8 in every 10 children are cured; but where diagnosis is late or treatment is left unfinished, that number is much lower [1]. In a national cancer registry from Iran, a middle-income country, 8 in every 10 children with cancer were alive 5 years later [10].
Children should be treated at a centre with a specialist children's cancer team [1], and treatment should be completed, on time. Read more: Is childhood cancer curable?
Frequently asked questions
My child bruises a lot; could it be leukaemia?
Most bruises in children come from knocks during play. But unexplained or very many bruises, especially with paleness, fever or tiny red spots under the skin, need a blood count [2, 4]. See symptoms of leukaemia.
When is a child's headache worrying?
Most headaches in children have a harmless cause. But morning headaches, headaches that get better after vomiting, or headaches with new problems in walking, balance, vision or behaviour should be checked promptly [5, 9]. In an awareness programme in the UK, recognising these signs roughly halved the time to diagnosis [6].
My child's pupil looks white in a photo; what should I do?
When are leg pain and limping in a child serious?
My child has had a swollen gland in the neck for a few weeks; should I worry?
Most swollen glands in children are not cancer: in general practice, fewer than 1 in every 1,000 children who came with a swollen gland had cancer [3]. But a gland that stays without a clear cause, or comes with fever, night sweats, breathlessness, itching or weight loss, should be seen by a specialist promptly [2]. See symptoms of lymphoma.
Can childhood cancer be found early with a screening test?
Is childhood cancer curable?
Yes; most childhood cancers are curable, as long as they are diagnosed early and treatment is completed fully and on time [1, 10]. Read more: Is childhood cancer curable?
Referral criteria in children (for physicians)
For physicians
NICE NG12 (children and young people up to 24 years). Unexplained petechiae or hepatosplenomegaly: immediate referral (within a few hours) for assessment for leukaemia. A very urgent full blood count (within 48 hours) for pallor, persistent fatigue, unexplained fever, unexplained persistent infection, generalised lymphadenopathy, persistent or unexplained bone pain, and unexplained bruising or bleeding. A very urgent referral (within 48 hours) for: newly abnormal cerebellar or other central neurological function (brain tumour); unexplained lymphadenopathy or splenomegaly (lymphoma; taking into account fever, night sweats, shortness of breath, pruritus and weight loss); a palpable abdominal mass or unexplained enlarged abdominal organ (neuroblastoma, Wilms tumour) and unexplained visible haematuria (Wilms tumour). A very urgent X-ray for unexplained bone swelling or pain; a very urgent ultrasound for an unexplained lump that is increasing in size. Absent fundal red reflex: ophthalmology referral on a suspected cancer pathway. Treat persistent parental concern as a reason to refer, even when a benign cause is likely [2].
Primary care (1267 children aged 0 to 14 and 15,318 controls). Twelve symptoms raised the probability of cancer at least tenfold; the highest PPVs: pallor 0.41% (OR 84), head and neck mass 0.30%, mass elsewhere 0.11%, lymphadenopathy 0.09%, abnormal movement 0.08% and bruising 0.08%. Each of these symptoms combined with three or more consultations within 3 months raised the probability of cancer to between 11 and 76 in 10,000 [3].
Leukaemia (meta-analysis of 33 studies, 3084 children). Hepatomegaly 64%, splenomegaly 61%, pallor 54%, fever 53%, bruising 52%; recurrent infections 49%, fatigue 46%, limb pain 43%, lymphadenopathy 41%; 6% were asymptomatic at diagnosis. Palpation of the abdomen and lymph nodes and careful inspection of the skin are essential [4].
Central nervous system tumours (meta-analysis of 74 studies, 4171 children). In intracranial tumours: headache 33%, nausea and vomiting 32%, abnormal gait and coordination 27% and papilloedema 13%; under 4 years: macrocephaly 41%, nausea and vomiting 30%, irritability 24% and lethargy 21%. Symptoms of raised intracranial pressure were absent in more than half of the children; examine the visual and motor systems and assess growth and puberty [5]. The RCPCH guideline with the HeadSmart campaign reduced the median total diagnostic interval from 14 weeks to 6.7 weeks [6].
Retinoblastoma (4351 patients from 153 countries, 2017). The commonest reason for referral was leukocoria (62.8%), followed by strabismus (10.2%) and proptosis (7.4%). Median age at diagnosis was 14.1 months in high-income countries with 98.5% intraocular disease, and 30.5 months in low-income countries with 49.1% extraocular disease and 18.9% metastasis [7].
Related cancer types
Related questions
References
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