Experts reveal the 10 'red flag' symptoms that mean you could have cancer

A persistent cough, a sore that refuses to heal, unexplained weight loss and changing bladder habits.

They may seem innocuous, irritating facts of life.

But experts warn people not to dismiss them and six other key changes in the body, for fear they could be a sign of something far more sinister.

The 10 red flags for cancer are ingrained in the minds of doctors and healthcare workers the world over. 

1. A persistent cough

Red flag for... lung cancer

Most lung cancers do not cause any symptoms until they have spread too far to be cured.

But, symptoms do occur in some people in the early stages of lung cancer.

A new cough that does not go away, or changes in a chronic cough or 'smoker's cough' can be an early indication of the disease.

In addition, chest pain linked to coughing, deep breathing or lauging as well as hoarseness and coughing up blood are early warning signs.

2. A change in the appearance of a mole

Red flag for... skin cancer

Melanoma, the most deadly form of skin cancer, can appear anywhere on the body, but they most commonly appear on the back, legs, arms and face and even underneath a nail.

Though less common, they often spread to other organs in the body, making them more deadly.

The most common sign is the appearance of a new mole or a change in an existing mole.

Signs to look out for include a mole that is:

• getting bigger 
• changing shape 
• changing colour 
• bleeding or becoming crusty 
• itchy or painful

A helpful way to tell the difference between a normal mole and a melanoma is the 'ABCDE' checklist:

Asymmetrical – melanomas have two very different halves and are an irregular shape.

Border – melanomas have a notched or ragged border.

Colours – melanomas will be a mix of two or more colours.

Diameter – melanomas are often larger than 6mm (1/4 inch) in diameter.

Enlargement or elevation – a mole that changes size over time is more likely to be a melanoma.

3. A persistent chance in bowel habits

Red flag for... bowel cancer

The three main symptoms of bowel cancer are blood in the stools or faeces, a change in bowel habit, such as going more frequently, or having looser stools, and abdominal pain.

However, these symptoms are very common, and can easily be attributed to other conditions.

4. A sore that doesn't heal

Red flag for... many types of cancer

A sore or ulcer in the mouth that fails to heal is the most common symptoms of mouth cancer, according to the Cancer Treatment Centers of America.

Furthermore persistent pain in the mouth can also be a sign.

As for the rest of the body, experts at Cancer Research UK say a person should seek advise from a doctor if a spot, wart or sore doesn't heal after several weeks, even if it is painless.

The skin repairs itself very quickly and any damage should typically heal within a week or so. 

5. A persistent difficulty swallowing

Red flag for... oesophageal cancer

A number of medical conditions can make it difficult to swallow. 

But if you are having difficulty swallowing and the problem doesn’t go away after a couple of weeks, it should be checked out. 

The key sign of oesophageal cancer is a difficulty swallowing. This problem may contribute to weight loss, which can also indicate the disease is present.

6. Unexplained weight loss

Red flag for... a number of cancers

Most people with cancer will lose weight at some point. 

When you lose weight for no known reason, it’s called an unexplained weight loss, according to the American Cancer Society.

An unexplained weight loss of 10 pounds or more may be the first sign of cancer. 

This happens most often with cancers of the pancreas, stomach, esophagus (swallowing tube), or lung. 

Experts at Cancer Research UK add that small weight changes over time are quite normal, but if you lose a noticeable amount of weight without trying to, tell your doctor.

7. A persistent change in bladder habits

Red flag for... bladder or prostate cancer 

Problems urinating can include needing to pee urgently, more frequently, being unable to go when you need to, or experiencing pain. 

These symptoms can all be caused by conditions other than cancer, but it’s important to tell your doctor if you experience any of them. 

A slow or weak urinary stream, or the need to urinate more often, especially at night, can indicate prostate cancer specifically.

Blood in the urine is also a sign.

With bladder cancer, the disease can cause changes in urination, including having to urinate more often, pain or burning during urination and feeling as if you need to go right away, even if the bladder is not full. 

These symptoms are also more likely to be caused by a benign condition such as infection, bladder stones, an overactive bladder, or an enlarged prostate (in men). 

But, it is important to have them checked by a doctor so that the cause can be found and treated, if needed.

8. An unexplained lump

Red flag for...  many types of cancer

A great many cancers can be felt through the skin, though typically they occur in the breast, testicle, lymph nodes and soft tissues of the body.  

A lump or thickening of tissue can be an early sign of the disease, but it can also indicate some forms of the disease are in an advanced stage.

You should visit a doctor, especially if you have just found a lump or noticed a lump has grown in size.

The American Cancer Society note that some breast cancers can show up as red or thickened skin rather than a lump.  

9. Persistent, unexplained pain

Red flag for...  many types of cancer

Pain can present in the early stages of a number of cancers, but especially with bone and testicular cancers.

A headache that will not go away or get better with treatment can be a sign of a brain tumor.

Furthermore, back pain can indicate cancer of the colon, rectum, or ovary.

In most cases, where pain is felt and cancer is diagnosed it is an indication that the disease has spread from its primary location in the body.

10. Unexplained bleeding

Red flag for... many types of cancer, namely bowel, cervical or vulval cancer

In both the early and late stages of the disease, unexplained bleeding can occur.

Coughing up blood can be a sign of lung cancer, while blood in the stool is an indication of colon or rectal cancer.

Cancer of the cervix or the endometrium - the lining of the uterus - can cause abnormal vaginal bleeding.

Blood in the urine can indicate a person is suffering bladder, kidney or prostate cancer.

And a bloody discharge from the nipple may be a sign of breast cancer.  

Follow NEWS.am Medicine on Facebook and Twitter