A woman's guide to cancer screening and prevention tests

"Screening is very much like wearing your seatbelt when driving," says Professor Carol-Ann Benn, a surgeon with a special interest in breast cancer. "It won't prevent you from having an accident, but it will protect you if you do. Some screening tests are routine - for example, your gynae will perform a Pap smear (see detail below) as part of your regular check-up. Others are also done routinely at certain ages as a general precaution, while your doctor will decide how to screen and how often to do so if you have a high risk."

To determine which screening tests are best for you, your doctor needs the following information, says Professor Benn:

• Any cancers in your family, as well as the ages at which diagnoses were made. It's far more relevant to your doctor if two of your cousins had breast cancer under the age of 40, than if your gran passed away as a result of cancer at age 95.
• What other chronic conditions run in your family? These might include heart disease, diabetes and a tendency towards blood clots.

"It's also important," she adds, "to do your bit too. Get to know your body intimately. Regularly check your breasts and your skin for lumps and bumps. Discuss any unusual symptoms such as pain or bleeding with your doctor. And don't ignore anything out of the ordinary due to fear. Remember that knowledge is strength and the sooner you screen for abnormalities, the quicker you can get them sorted out."

What should you screen for, and when?

There's a great deal of controversy about how often to do the various screening tests," explains radiologist Dr Peter Schoub. "Most cancers become lethal once they metastasise (spread to vital organs). This spread usually only occurs once a cancer reaches a certain size. The goal of screening tests is to offer a relatively cheap, non-invasive test to a large population of people who are otherwise healthy, to pick up problems before they become symptomatic. As a general rule, consultation with your trusted GP or specialist doctor is advisable. You need to understand your risks of developing a certain cancer, and the benefits and flaws of each screening test - which constitutes informed consent and personal choice. The general principle though, is that early detection of cancer allows for life-saving treatment."

Estimate your risk of female cancers: Discovery Health's MyFamilyHistory tool

Use the Discovery Health's MyFamilyHistory tool to record your family health history and estimate whether you have a higher-than-average risk of developing a female cancer or other conditions.

Breast cancer

Breast cancer is the most commonly-occurring cancer in women worldwide and is estimated to affect one in eight women according to Dr Schoub. "If caught early and treated appropriately, the prognosis is excellent," he explains, so the key is early detection.

The guidelines for the highest survival benefit are as follows:

• First mammogram at age 40
• Regular mammograms as discussed with your healthcare provider
• No older age limit. Unless you have less than a 10-year life expectancy, mammograms have been shown to be beneficial.

Breast ultrasound is often added to mammography, particularly in women who have dense breast tissue, but it cannot replace mammograms as a screening test.

Breast MRI is the most sensitive test for breast cancer. MRI (magnetic resonance imaging) is an exceptionally accurate cancer-detecting tool that uses a magnetic field in combination with intravenous contrast to show malignancy and precancerous conditions. MRI is able to detect some abnormalities that are otherwise invisible on a mammogram and ultrasound, and is recommended as a screening test if you have a high lifetime risk of breast cancer - a strong family history or if you have the BRCA gene mutation.

Dr Noluthando Nematswerani adds: "Screening for a cancer as common as breast cancer is of utmost importance in the prevention of late-stage breast cancers and in ensuring the best possible treatment outcomes for patients. Women should understand how to do breast self-examinations too, and should stick to a regular monthly routine so that any lumps or changes in the breast can be detected as early as possible. Members of a medical scheme administered by Discovery Health, are covered for one mammogram every two years, as per international guidelines, paid for from their Screening and Prevention Benefit. But, we emphasise that members who are at high risk are eligible for a yearly mammogram and should discuss their screening regimen with their healthcare professional. High-risk members who qualify for an MRI will also have access to this sort of screening test."

Use the Discovery Health's MyBreastCancerRisk calculator to estimate whether you have a higher-than-average risk of developing breast cancer.

Cervical cancer

Cancer of the cervix is the second most common cancer in South African women, explains Dr Schoub.

A Pap smear screening test is usually performed by your gynaecologist using a speculum and a special swab, and is a sensitive way to pick up abnormal tissue before it develops into cancer. Discovery Health's Head of Clinical Policy Unit, Dr Nematswerani adds: "If you are at high risk of cervical cancer, speak to your clinician to advise on the appropriate screening test and frequency of screening."

You should start having Pap smears from the age of 25, unless you are HIV positive (if so, you would have been tested at a younger age). These should be done every three years, unless abnormal cells are found, in which case more frequent smears may be recommended. You should have these screening tests up until age 65 unless abnormal cells were identified in the 10 years prior. In that case, regular Pap smears should continue beyond age 65 (for 20 years after the date the abnormal cells were found). You do not require a Pap smear if you've had a hysterectomy.

Increasingly, newer swab tests for human papillomavirus (HPV) are being done every five years in addition to Pap smears. HPV is the underlying cause of most cases of cancer of the cervix.  Very importantly, HPV vaccinations have been shown to be highly effective in preventing the development of cancer of the cervix. The vaccine prevents infection of the cervix with HPV which in turn, prevents cancer cells developing. Teenagers should be vaccinated before becoming sexually active and should still have regular Pap smears.

Dr Nematswerani adds: "All females on Discovery Vitality who are between nine and 25 years old will earn Vitality points for having the HPV vaccination - 1 000 Vitality points will be awarded after the completion of the three-dose schedule. Members of a medical scheme administered by Discovery Health are covered for these vaccination from the available funds in their Medical Savings Account. The costs do not accumulate towards the Annual Threshold."

Ovarian cancer

Ovarian cancer is on the rise, but only a small percentage (20%) of cases are detected in the early stages. If you're over the age of 55 or have a family history of ovarian cancer, a transvaginal ultrasound, as well as a CA-125 blood test could help to pick it up early. Chat to your gynae about your risk and whether or not to screen for this sort of cancer.

Colon cancer

Colon cancer is relatively common among people worldwide (second most common cancer in men and women) and has a poor prognosis when caught at a late stage.

You should start screening at the age of 50 if you're not at high risk. This involves having:

• An annual occult blood faecal assessment based on the fact that most colon cancers bleed. If this test is done regularly, it's very effective at picking up colon cancer early.
• A 10-yearly colonoscopy to examine your whole colon under sedation. This enables your specialist to detect small cancers and polyps and to take biopsies (tissue samples) during the procedure. The alternative is to have a five-yearly sigmoidoscopy, which is less invasive (no sedation but this covers only the lower part of your colon).

You'll have a higher risk of colon cancer if you have a family history of colon cancer, a personal history of colon polyps, inflammatory bowel disease and certain genetic disorders. You should then start screening earlier - at age 40 or 45 - and do more regular screening, every three to five years. Remember that colon screening is often done on an individualised basis, so you should always discuss your risk profile as well as the best way to screen with your doctor.

Lung cancer

Lung cancer is the most common lethal cancers for men and women worldwide. The vast majority of lung cancers are smoking-related (± 85%). While lung cancer screening tests using regular CT scans of the chest are the norm in the USA for specific groups of at-risk patients, guidelines for lung cancer screening are not yet widely adopted in South Africa. If you're aged between 55 and 80, and have smoked one pack of cigarettes a day for 30 years you should have an annual CT scan of the chest. This applies whether you are currently smoking or have stopped smoking during the past five years, and have at least a 10-year life expectancy. CT scans are very accurate at picking up tiny nodules in the lungs that represent early cancers. If treated at this stage, the prognosis is usually good.

Skin cancer

According to CANSA, South Africa has one of the highest monitored ultra violet levels in the world, and as a result, one of the highest skin cancer rates globally. In our sunny climate you need to be extra vigilant if you:

• Are fair-skinned
• Have red hair
• Have a family history of melanoma
• Have albinism
• Had extended sun exposure and sunburn, particularly when you were young.

Melanomas are the most dangerous form of skin cancers and can be fatal when they spread to other parts of your body. The good news is that when detected and treated early, melanomas are usually curable. This is why you need to pay careful attention to your skin. Be sun-safe and wear hats and sunglasses and use sun block whenever you go outdoors. Regularly check your skin for moles that change, grow, bleed or darken, as well for as for sores or scabs anywhere on your body that don't go away. A good skin examination by your doctor is advisable, and you may be referred to a dermatologist to monitor your moles using a specialised technique - a dermoscopy - if necessary. Future consultations, depending on your risk profile, will either be annual, or as your doctor suggests.