Cancer Screening: Be informed!

Cancer is a scary word. It’s a word that we are all brought up to dread. We all know someone who has been affected by cancer. Unfortunately, cancer accounts for 1 in 4 deaths and is the leading cause here in the UK.

Figure: The number of cancer registrations by the 24 major sites, England, 2015 Office for National Statistics

In the UK, the most common type of cancer to affect men and women are lung cancer followed by bowel cancer.
In men, Prostate is the second biggest killer and in women it is Breast cancer.

Fortunately, since the 1970s there has been a reduction in mortality from these types of cancer on average by 25% due to early detection and advancing treatments.

Is cancer preventable?

In some cases cancer is preventable. There are certain lifestyle behaviours such as smoking and poor diets that are well known culprits for causing cancer.
However some us are more prone to cancer due to our genetic make-up. Whilst we cannot change this- we can do genetic testing to determine our risk for certain types of cancer and be offered preventative treatment.

In 2013, Angelina Jolie underwent an operation to have both her breasts removed as her genetic tests revealed a mutation in the BRCA1 gene which meant that her lifetime risk of developing breast cancer was 87%. The same problem with this gene gave her a 53% lifetime risk of developing Ovarian cancer and so she had an operation to remove both her ovaries in 2015. Whilst all these types of operations can seem pretty drastic for some, for Angelina the knowledge of her probability of developing cancer gave her the opportunity to make her own informed decisions.

Being informed and knowing what your choices are is key in making the right decision for you.

What is screening?

Screening is the process of trying to find people with either a high risk of developing cancer or finding the actual disease at the earliest stage possible.

Why are some cancers screened for and not others?

Many available tests are too complicated and/or expensive to be offered to the wider population and are beyond the resources of the NHS. Currently, under the NHS, cancer screening is only offered for breast, cervical and bowel cancer.

Privately, you may access screening for other types of cancer. The most important deciding factor as to what you should be screened for and how often is a thorough cancer risk history undertaken by a highly-experienced physician.

Some of the tests screen for the actual disease being present whilst others, genetic tests, screen for your genetic predisposition of developing a cancer.
So, what screening tests are available to detect cancer?

• Lung Cancer
o No screening available on the NHS.
o Privately, following USA guidelines, a low dose CT chest in adults over the age of 50 who have a significant smoking history, currently smoke or have quit within the past 15 years is available.

• Bowel Cancer
o NHS offers stool test every 2 years for adults aged between 60-74. The stool test however fails to detect most polyps and some cancers.
o Privately a stool test is available at an earlier age on annual basis. A Colonoscopy however is the most sensitive test and this is offered every 5 years for screening purposes.

• Prostate Cancer
o No screening available on the NHS.
o Privately, this is part of an annual health check in men over the age of 40 and screening consists of prostate examination and PSA testing (total and broken down ratios of PSAs which are more sensitive in picking up Prostate Cancer).

• Breast Cancer
o NHS offers a mammogram to all women over the age of 50 every 3 years. In some parts of the country, this age has been lowered as a trial to 47-48.
o Privately women are offered digital mammography screening over the age of 40, every 12-18 months. Breast densitometry evaluation also provides information as is known that denser breasts are associated with an increased risk of developing breast cancer.

• Ovarian Cancer
o No screening available on the NHS.
o The problem with the ovarian cancer is that in most cases the cancer is discovered in late stages. A thorough annual health check will identify subtle changes in one’s body habits. This, combined with gynaecological and abdominal examination, ultrasound scanning and blood tests for ovarian cancer marker (ROMA- risk of ovarian cancer algorithm) provide the best current screening for Ovarian Cancer.

• Cervical Cancer
o NHS offers cervical smear tests every 3 years in women aged 25-49 and every 5 years aged 50-64.
o Privately cervical screening starts much earlier, correlating with a woman’s sexual activity and is offered on annual basis part of the well woman checkup. HPV vaccination forms part of the fight against cervical cancer.

• Skin Cancer
o No screening available on the NHS.
o Privately, skin examination and identification of suspicious lesions is part of an annual health check. Early detection allows for early treatment and cure.

Most other cancers may be identified early as part of an annual health check. History combined with examination and simple tests such as urine analysis and a blood count test for example may identify a bladder, a kidney or a blood cancer early.

Genetic Testing

Genes are the body’s instructions determining how the body develops and is maintained. Some genes prevent cancer developing but if there is a mutation in one of these genes it doesn’t work correctly and this causes an increased risk of cancer. It is estimated that 5-10% of cancers are thought to be caused by genetic mutations.

It has been found that there are mutations in multiple genes that can cause an increased risk of certain types of cancer. However, there are other genes which are also associated with cancer and current research is attempting to understand these other genes.

So far genetic testing is available for breast, ovarian, prostate and bowel cancer.
How do you know if you are at risk of having these mutations? Generally speaking, hereditary cancer shows following clues in your family history such as having several relatives with one particular type of cancer and/or several relatives having multiple types of cancer and cancer diagnosed in a family member at a young age.

Genetic testing can help determine the risk of cancer within a family and guide appropriate cancer screening. Depending on the specific genetic risk different screening tests can be arranged and risk-reducing strategies can be considered.

Genetic testing usually involves a blood test and the results take 4 weeks to arrive.
It is very important to know that no test is 100% and it is possible that someone could have a genetic mutation which is not detected by the test. It is most accurate to perform genetic testing on a family member who has had a particular type of cancer so that a possible genetic cause can be found in the family. If this is not possible, genetic testing can be performed on someone who has not had cancer, although if the results are normal this will not be as informative.

There are 3 possible results from genetic testing:

• A mutation is found in one of the genes which is known to increase the risk of a particular type of cancer. Increased screening and/or risk- reducing techniques would be recommended.
• A genetic variation is found, but whether or not this is the definite cause of cancer is unknown. Screening would be recommended based on the family history.
• No mutation is found. It is possible that there may be an undetectable mutation or a mutation in a different gene. Cancer screening may still be beneficial.

If you have a mutation this means that you have an increased risk of the cancer that was checked for and possibly other cancers. Your exact risk will depend on which gene mutation has been found. It would also be possible to offer predictive testing to other people in your family to see if they also have that specific mutation that has already been identified.
Screening tests would then be employed to look for that particular cancer as well as other cancers known to be caused by the mutation too.

Vaccines to prevent cancers?

Human Papilloma Virus (HPV) vaccination is recognised as being the cervical cancer vaccine. The latest Gardasil 9 vaccine prevents against 9 strains of the HPV virus versus only 4 strains previously available.

Hepatitis B vaccination also prevents liver disease and liver cancer. Hepatitis B vaccination is widely available in mainland Europe but not in the UK. Despite an increase in Hepatitis B cases in the UK and increased immigration from countries where Hepatitis B is a major health concern, UK has not adopted an universal Hepatitis B vaccination programme.

There are no other vaccines available to prevent cancers at present.

What to do if you think you are at risk?

If you would like to discuss your risks of cancer and know what types of screening tests are available for you, you should arrange to see a doctor.

At ROC, we offer personalised annual assessments with a cancer screening programme in place for your individual risks. Some screening tests may not be applicable to you, or may be applied with a lesser or higher frequency than described above. It is not just the age and your family history that matters; ethnicity can be as important.
Getting to know your risks, your health parameters over a period of years also helps identify early changes, aid early diagnosis and treatment of cancers and other illnesses.