Signs of cancer

There are many signs of cancer and symptoms – but remember that having any of them doesn’t necessarily mean you have cancer.

Five common signs of cancer in young people

  • There are five common signs of cancer in young people, these are:
    1. Lumps
    2. Unexplained tiredness
    3. Mole changes
    4. Pain
    5. Significant weight change 
  • It’s important to get anything you’re not sure about checked 
  • These symptoms don’t necessarily mean you have cancer, but it’s best to check

It’s really important to get checked out if you have any of the symptoms below – especially if they last for a while and you can’t explain them. 

Signs of cancer

Lumps, bumps and swellings

These could be anywhere in your body.

Signs of cancer - lumps, bumps and swellings
Signs of cancer  - unexplained tiredness

Unexplained tiredness

When you feel completely exhausted, all of the time, and even a good night’s sleep doesn’t help.

Mole changes

This could be a change in the size, shape, colour or texture of a mole, or if it starts bleeding.

Signs of cancer - Mole changes
Signs of cancer  - Persistent pain


The kind of pain that’s persistent and extreme, and doesn’t go away when you take painkillers.

Significant weight change

This could be weight loss or weight gain, when you haven’t changed your diet, how much exercise you’re doing, or any medication you’re on.

Signs of cancer  - Significant weight change

Hear from young people on the importance of getting diagnosed early:


Do you know the 5 common signs of cancer in young people aged 13-24? 🔴 Lumps, bumps and swellings 😴 Unexplained tiredness ⁉️ Mole changes ⚡️ Persistent pain ⚖️ Significant weight change #WorldCancerDay #TYACancer #CancerSymptoms

♬ original sound - Teenage Cancer Trust

Other signs of cancer and symptoms to watch out for

  • Headaches or dizziness that won’t go away
  • Getting out of breath more easily than normal
  • Bleeding you can’t explain – for instance in your urine or poo, after sex, between periods, or if you vomit
  • Unexplained bruising
  • Ongoing changes when you go for a poo – like constipation or diarrhoea (or both), pain, or feeling like you’ve not quite finished going
  • Sweating a lot at night.

It’s really important to contact your GP if you’re worried about any of these signs of cancer. 

If it turns out not to be cancer, you haven’t wasted anyone’s time. You’ll still be listened to and taken seriously – the NHS is actively encouraging people to contact their GP if they’re worried about possible cancer symptoms. 

If it does turn out to be cancer, then getting diagnosed early is really important, as early treatment will improve the outcome. 

Either way, you’ll have done the right thing.

Signs of cancer and talking to your doctor

Your doctor will want to know as much as possible about what’s going on, but it’s easy to forget things – so it’s worth writing everything down before your appointment. Think about: 

  • What problems you’re having 
  • How long you’ve had them 
  • Whether the problems are permanent or come and go 
  • Whether they’re getting worse. 

And if you realise that you’ve forgotten something after speaking to your doctor, it’s important to arrange another appointment. You’re never wasting your doctor’s time.

If you’re worried about signs of cancer...

It’s normal to feel nervous before speaking to your doctor. Plenty of young people feel awkward discussing their bodies. And you might feel worried about what you could find out. 

It can help to: 

  • Write down what you want to say and ask beforehand 
  • Make a note of your symptoms and when you started to feel unwell 
  • Share as much information as possible – little details can make a big difference 
  • Have someone from your family attend the appointment with you 
  • Be open and honest – remember that doctors talk to people about all kinds of problems all day, every day 
  • Ask your doctor to repeat anything you don’t understand 
  • Make sure you know what will happen next before you finish the appointment 
  • Make notes about the conversation that will help you remember afterwards. 

Conversations with doctors don’t always go to plan. So if you don’t feel your first appointment goes well, make another one. If that doesn’t go well, make another one again. 

You can ask to see another doctor too, if that helps. Don’t worry, doctors won’t be offended if you ask for a second opinion – and remember you have a right to be taken seriously.

More information about cancer

Help us spread the word about signs of cancer

Download a printable A3 poster to help you share the five most common cancer warning signs for young people: