Know the signs.
Act sooner.
Most cancers are more treatable when caught early. Learning to recognise the warning signs — and acting on them promptly — can make a life-changing difference.
Important: This information is for awareness purposes only and does not replace professional medical advice. If you are concerned about any symptom, please contact your GP or call NHS 111.
Symptoms that should always be checked
These symptoms can be caused by many conditions — but if they are persistent, unexplained or new, they should be discussed with your GP.
Unexplained weight loss
Losing weight without trying, particularly if rapid or significant.
Persistent fatigue
Extreme tiredness that does not improve with rest.
Unexplained pain
Pain that is new, persistent or has no obvious cause.
Persistent cough or hoarseness
A cough lasting more than 3 weeks or a change in your voice.
Changes in bowel or bladder habits
Persistent changes that last more than a few weeks.
Unusual bleeding or discharge
Blood in urine, stools, or unusual vaginal or nipple discharge.
A lump or thickening
Anywhere on the body, especially if new or growing.
Difficulty swallowing
Persistent problems swallowing food or liquids.
Symptoms by cancer type
Different cancers present with different symptoms. Here are the key warning signs for the most common cancers in the UK.
Breast Cancer
- A new lump or thickening in the breast or armpit
- Change in size, shape or feel of the breast
- Skin changes — dimpling, puckering or redness
- Nipple discharge, inversion or change in appearance
- Persistent pain in the breast or armpit
Bowel Cancer
- Persistent change in bowel habits lasting 3+ weeks
- Blood in stools without an obvious cause
- Abdominal pain, discomfort or bloating
- Unexplained weight loss
- Extreme tiredness for no obvious reason
Lung Cancer
- A cough that does not go away after 3 weeks
- Coughing up blood
- Persistent breathlessness or chest pain
- Unexplained weight loss and fatigue
- Hoarseness or changes to your voice
Prostate Cancer
- Needing to urinate more frequently, especially at night
- Difficulty starting or stopping urination
- Weak or interrupted urine flow
- Blood in urine or semen
- Discomfort in the pelvic area
Cervical Cancer
- Unusual vaginal bleeding — between periods, after sex or after menopause
- Vaginal discharge that is unusual in colour, smell or amount
- Discomfort or pain during sex
- Pelvic pain unrelated to your menstrual cycle
Skin Cancer
- A new mole or change in an existing mole
- A mole that is asymmetrical, has irregular borders or multiple colours
- A mole larger than 6mm or growing in size
- A sore that does not heal within 4 weeks
- Itching, bleeding or crusting of a mole or skin lesion
Why people delay — and why you shouldn't
Research shows that many people delay seeking help for cancer symptoms. Understanding these barriers is the first step to overcoming them.
Common barrier
Worry about wasting the doctor's time
Your GP is there for exactly this. No symptom is too minor to discuss.
Common barrier
Fear of what the doctor might find
Earlier diagnosis means more treatment options and better outcomes.
Common barrier
Assuming symptoms will go away
Persistent symptoms lasting 3+ weeks should always be checked.
Common barrier
Not recognising symptoms as serious
Many cancer symptoms are subtle. If something feels different, trust your instincts.
If in doubt, get it checked
You do not need to be certain something is wrong to see your GP. If a symptom is new, persistent or worrying you — that is reason enough to make an appointment.
Symptoms lasting 3+ weeks
Book a GP appointment
Sudden or severe symptoms
Call NHS 111 or your GP urgently
Emergency symptoms
Call 999 or go to A&E
Frequently asked questions
Answers to the most common questions about cancer symptoms and when to seek help.
Last reviewed: · Content aligned with NHS and NICE clinical guidance.