Breast Cancer Screening: Section 1.a.

CONTENTS:

1.1 Introduction to Breast Cancer Screening

Welcome to page 1 of our breast cancer website and look out for Moose!

1.2      What Are The Models for Predicting Breast Cancer Risk?
1.3      Breast Cancer Screening Rates and Mortality Reduction
1.4      What Are The Latest Recommendations for Breast Cancer Screening?
1.5      What is the Reduction in Breast Cancer Mortality Due to Screening?
1.6      What are the Benefits and Risks of Breast Cancer Screening?
1.6.1    Benefits
1.6.2    Risks
1.6.3    Recommendations for 6-Monthly Mammograms

Welcome to Page 1 of our breast cancer website. I hope that you brought waffles…or pancakes…Glass of wine?…Anything?

Forward to 1B on screening results. You are currently on page 1A introducing screening.

Breast cancer screening programs have created a large amount of clinical and research data. This data is all readily available on the internet.

The topic is all about getting mammograms regularly after age 40 .

My doctor told me I had attention deficit something-or-other….Oh Look! A mammogram!

Introduction to Breast Cancer Screening

Breast cancer mammographic ‘screening‘ is done to detect abnormalities in the breast that may require monitoring or treatment. The most important role of mammography is to detect early, treatable breast cancer.

So, for every 1,000 women who undergo breast cancer screening, there will be between 3 and 5 breast cancer diagnoses. There is evidence that suggests breast cancer screening programs are saving lives, by detecting breast cancer at an early and more treatable stage.

Screening programs are saving lives, that’s good news isn’t it?

Yes. Life is beautiful, look after it.

…and remember if anyone mentions ‘a balanced diet’ this means a cupcake in each hand!

Another important goal of breast cancer screening programs is to encourage women to begin to participate in screening at an earlier age and to have re-tests every one to two years.

The most common forms of breast cancer develop in the breast ducts and lobules. Because a malignant tumor of the breast develops from the lining epithelial cells of the breast ducts or lobules, ‘carcinoma,’ is the common term, or ‘cancer’ or ‘malignant tumor.’

Ductal carcinoma is the most common type. Lobular carcinoma, another type, begins in the breast lobules (or milk glands).

An ‘invasive’ breast cancer has spread from the breast ducts or lobules and into the surrounding normal breast tissue.

And sadly, some people aren’t survivors…

That’s right. Even though we mix fun with serious topics, the information is true, important and helpful.

New cases and Mortality of Breast Cancer

The World Health Organization (WHO) have calculated the new cases of breast cancer in the U.S. and the mortality from breast cancer in the U.S. in 2014:

New cases: 232,670 (female); 2,360 (male)
Deaths: 40,000 (female); 430 (male)

When a breast lump is discovered by breast self-examination, it is likely to be benign in 80% of cases. There is no evidence that the introduction of breast self-examination has reduced mortality rates from breast cancer.

My New Years resolution is to be a better listener, and for other people to stop wanting piggy-back rides.

What Are The Models for Predicting Breast Cancer Risk?

There are models to calculate an individual’s lifetime risk of developing breast cancer and there are models that predict an individual’s likelihood of having a BRCA1 or BRCA2 gene mutation.

However, to use breast cancer models effectively, each patients detailed clinical characteristics, together with their family history, are necessary.

Wow! That’s a good service, a model predicts the risks. Are they male or female models?

No Hector, they’re clinical risk assessment models.

Why do models always smile in lightning storms? They think they’re getting their picture taken.

Are they blonde?

Two Common Risk Assessment Models for Breast Cancer

The two most common breast cancer risk assessment models are Gail, (1989) and Claus et al. (1993). Indeed, these two models may not be applicable worldwide because they were developed with particular populations in mind. The Claus model and the Gail model are useful in clinical patient counselling and research studies. But both methods have their limitations, with the risk estimates derived from the two models sometimes giving different risk predictions for each patient analyzed (Gail, 2010).

Several breast cancer models can predict the probability of identifying germ line BRCA1/BRCA2 mutations, either in individual patients or in families.

I got a 1.5 % risk factor on the Myriad model.

I got 2.6 % I think because my auntie had breast cancer.

That’s still quite a low risk Jess.

These models have included using logistic regression, Bayesian analysis of genetic models and also empiric observations, including the use of prevalence tables, such as Myriad.

Using complex segregation analysis, a polygenetic model (BOADICEA) examines both breast cancer risk and the probability of having a BRCA1 or BRCA2 mutation (Antoniou et al., 2004). Access to this is now available to individuals on line (BRCAPRO and Breast and Ovarian Analysis of Disease Incidence and Carrier Estimation Algorithm [BOADICEA])

Breast Cancer Screening Rates and Mortality Reduction

The longer the time interval between screenings, the greater the likelihood of detecting breast cancer.

For yearly screening, the cancer detection rate is between 0.5% and 0.6%. For 2-year screening, the detection rate increases to between 0.65% to 0.85%, while the three-year screening interval detects cancers at a rate of 1.0% to 1.3%.

So, in brief, women between 40 and 49 years old and those over 70 should be screened once a year. Those between 50 and 69 years should be screened every 18 to 24 months.

How often? Age and Breast Cancer Screening

Women aged between 50 and 69 years of age should be screened for breast cancer approximately every 18 months, regardless of risk factors.

The American Cancer Society and the National Cancer Institute (NCI) both recommend annual or bi-annual screening for women between 40 and 49 years of age, if at average risk.

However, recent evidence suggests that tumors may grow more rapidly in younger women, so the trend is to recommend annual screening for all women aged between 40 and 49 years of age.

For women between 40 and 49 years of age, and for women over 70 years of age, breast screening should be done annually if there are risk factors present that make breast cancer more likely.

Corduroy pillows: They’re making headlines!

Risk Factors for Breast Cancer

A family history of breast cancer (sister, mother, daughter).
Previous chest or thoracic radiation therapy history (e.g., for Hodgkin’s lymphoma) before the age of 30 years.
Family history of BRCA1 and BRCA2 gene variants.
First pregnancy at 30 years of age or older.
Late menopause.
More than four years of hormone replacement therapy (HRT).

You can find out your own risk factor and have regular mammograms.

This could save your life, the earlier the cancer is found the better the outlook.

Come on ladies! You don’t have mammograms because it pinches, pulls and squeezes….so do those skinny jeans!

Early detection with the most appropriate treatment is the most effective strategy to reduce breast cancer mortality.

Mammography screening for breast cancer is not only expensive but involves substantial manpower and financial resources. It is not a feasible approach in developing countries.

Studies on the efficacy of early detection programs, based on clinical breast examination (CBE) and breast self-examination (BSE) remain inconclusive and rather controversial.

That’s a shame, I rather like checking my boobs once a month.

Well don’t stop – it can’t be doing any harm.

Improving breast cancer patients Survival

There are three main approaches that could improve patient survival in breast cancer:

Firstly, increasing the awareness of the population of important breast cancer symptoms and signs.
Second, more information on the improved prognosis associated with treatment of early-stage disease needs to be understood by patients.
Third, the provision of readily accessible and effective diagnostic and treatment services are important.

I should have asked more questions, before I got the pet Llama. Now it sleeps on my bed and I’m on the floor.

What Are The Latest Recommendations for Breast Cancer Screening?

Since 2009, the American Academy of Family Practitioners (AAFP) recommends that family physicians should discuss with each patient under the age of 50, the benefits of screening for breast cancer. The AAFP recommends biennial (every two years) screening mammography for women between ages 50 and 74. The AAFP concludes that the current evidence is insufficient to assess the benefits and harms of screening mammography in women aged 75 years and older.

The United States Preventive Services Task Force (USPSTF) has summarized the current best evidence regarding breast screening to help to guide physicians and patients. So, the recommendations of the USPSTF apply to women who do not have a higher risk of developing breast cancer and apply to routine screening procedures.

The latest recommendations for breast cancer screening, for early breast cancer detection in women without breast symptoms, come from the American Cancer Society (ACS) in September, 2014.

Two silk worms had a race they ended up in a tie.

Summary of Breast Cancer Screening Recommendations

This is a summary of the recommendations, taken from the full ACS report:

Women age 40 and older should have a mammogram every year and should continue to do so for as long as they are in good health.

Women in their 20s and 30s should have a clinical breast exam (CBE) as part of a periodic (regular) health exam by a health professional preferably every 3 years.

Starting at age 40, women should have a CBE by a health professional every year.

Breast self-exam (BSE) is an option for women starting in their 20s. However, women need to be aware of the benefits and limitations of BSE. A health professional should be aware of any unusual breast changes straight away.

Women who are at high risk for breast cancer due to certain factors, need a MRI and a mammogram every year.

I’m going to start telling women that I’m available for a limited time only, in the hope that their shopping instinct will kick in!

Risks of Breast Cancer

The risks of breast cancer are for women who:-

Have a lifetime risk of breast cancer of about 20% to 25% or greater, according to risk assessment tools that are based mainly on family history (such as the Claus model).
Carry the BRCA1 or BRCA2 gene mutation.
Have a first-degree relative (parent, brother, sister, or child) with a BRCA1 or BRCA2 gene mutation, and have not had genetic testing themselves.
Had radiation therapy to the chest when they were between the ages of 10 and 30 years.
Have Li-Fraumeni syndrome, Cowden syndrome, or Bannayan-Riley-Ruvalcaba syndrome, or have first-degree relatives with one of these syndromes.
The American Cancer Society recommends against MRI screening for women whose lifetime risk of breast cancer is less than 15 %.

Do you agree with this Doc?

Pretty much, yes, at the moment.

The Conclusion of the American Cancer Society (ACS)

“Without question, a physical exam of the breast without a mammogram would miss the opportunity to detect many breast cancers that are too small for a woman or her doctor to feel but can be seen on mammograms.

Mammograms are a sensitive screening method, but a small percentage of breast cancers do not show up on mammograms but can be felt by a woman or her doctors. For women at high risk of breast cancer, such as those with BRCA gene mutations or a strong family history, both MRI and mammogram exams of the breast are recommended.”

The full recommendations from the American Cancer Society, September 2014, can be found here.

This is the most important part of this page.

But there’s too many facts, not enough fun story-telling.

What is the Reduction in Breast Cancer Mortality Due to Screening?

Have breast cancer screening programs reduced mortality? Medical reports suggest that breast cancer mortality rates have dropped by around 40% over the past ten years. Statistics show a recall rate of about 6%.

In addition, between 470 to 500 women need to undergo breast cancer screening for one single woman’s life to be saved.

Procaffinating: The tendency to not start anything until you’ve had a cup of coffee.

For women aged between 40 and 49 years of age, there is a reduction in the mortality rate from breast cancer, when screening is done at intervals of less than two years. The growth rate for breast cancer is typically more rapid for women in the 40 to 49 year age group.

Screening for breast cancer is recommended every 12 to 18 months. It is estimated that the mortality rates from breast cancer may be reduced by almost 30% by screening at this interval.

Mortality rates from breast cancer in women aged between 50 and 69 years may be reduced by almost 40% by regular screening.

Here’s a fun fact: you cannot breathe through your nose with your tongue out.

Here’s another. I bet you just tried to do that.

Reduction of Mortality in relation to Breast Cancer Screening

The National Cancer Institute (NCI) has reported that when screening mammography commenced at age 40 to 49 years, it resulted in a 5% decrease in mortality rate during a 5 year period, and a 25% decrease in mortality rate during an 18 year period.

If screening is initiated in the 50 to 64 year old age group, there is a 40% decrease in mortality at 9 years, a 30% decrease in mortality at 10-14 years, and a 21% decreased mortality rate at 18 years.

Never do anything that you wouldn’t want to explain to the paramedics.

But, a major concern is compliance with breast cancer screening programs. Women over 50 years of age seem to be far more inclined to attend annual screening checkups when compared to women under 50 years of age

Breast cancer survival rates vary greatly worldwide. They range from 80% or more in Sweden, Japan and North America to around 60% in developed countries and below 40% in developing countries (Coleman et al., 2008).

Low survival rates for breast cancer in women in undeveloped countries is explained mainly by the lack of early detection programs. This lack of early detection of breast cancer results in a high proportion of women presenting with late-stage disease. In less developed countries, the problem is compounded by a shortage of adequate diagnosis and treatment facilities.

What are the Benefits and Risks of Screening Mammography?

1.6.1 Benefits

As mammographic screening results in the reduction of mortality due to breast cancer, the expected benefits are believed to outweigh the risks. It must also be remembered that this is a non-invasive way to examine the breast tissue.

My Grandpa started walking five miles a day when he was 60. Now he’s 97 years old and we don’t know where he is!

Risks

Breast cancer detection with mammography uses a low-dose X-ray as the initial diagnostic tool. As with all X-rays, there are potential risks to the procedure. Frequent use of X-rays of any kind is not recommended for young people.

The average glandular dose of radiation for two exposures with a grid is about 1.6 to 2.0 mGy (0.16-0.2 rad). The average dose of radiation from a breast X-ray is about the same as background radiation exposure during a round trip by airplane from Denver to New York or travelling 1000 km in a car. The benefits of breast cancer screening vastly outweigh the potential health risks due to radiation exposure.

If you’re anxious and you know it….clasp your hands.

i.’False Negative’ Mammography

Mammography can image up to 90% of the breast tissue, which means there is a 10% chance that if a small tumor is present, it may not be detected; this is called a ‘false negative‘.

ii. ‘False Positive’ Mammography

A ‘false positive’ refers to a finding of a tissue abnormality which is non-cancerous.

iii. Early Recall for Follow-Up Imaging

Requests for follow-up imaging create a high degree of anxiety. About 9 % of women who are re-called for follow-up because they have a screening abnormality, will not attend.

I would be very stressed if I was called back for an abnormality.

Look on the bright side though ‘stressed’ spelt backwards is ‘desserts’.

…and don’t forget most recalls still turn out to be benign.

So, if a woman has a higher than average family history of cancer, this seems to motivate them to attend for follow-up mammograms.

Of course, the majority of follow-up mammograms turn out to show benign breast changes.

Life is too short to be serious all the time, so if you can’t laugh at yourself, call me. I’ll laugh at you.

Recommendations for 6-Monthly Mammograms

If a patient has breast preservation surgery for cancer, specialists recommend six monthly mammograms as a follow up. Furthermore, the affected breast needs to undergo screening six monthly for the first five years and the non-affected breast annually.

Other breast problems, such as spontaneous nipple discharge, a personal or family history of breast cancer, or other histological anomalies from a previous biopsy, are indications for a follow-up mammography.

There’s always a light at the end of the tunnel just pray it’s not a train!

References:

Gail, M.H., Brinton, L.A., Byar, D.P., et al. (1989). Projecting individualized probabilities of developing breast cancer for white females who are being examined annually. J Natl Cancer Inst 81, 1879-86. doi: 10.1093/jnci/81.24.1879 (Retrieved October 23rd 2014): https://www.ncbi.nlm.nih.gov/pubmed/2593165?dopt=Abstract

Gail, M.H., Mai, P.L. (2010). Comparing breast cancer risk assessment models. J Natl Cancer Inst 102(10), 665-8. (Retrieved October 24^th 2014): https://www.ncbi.nlm.nih.gov/pubmed/20427429

More references for this section are on this page.

Patient Information

American Cancer Society American Cancer Society recommendations for early breast cancer detection in women without breast symptoms. (Retrieved February 12^th 2015): http://www.cancer.org/cancer/breastcancer/moreinformation/breastcancerearlydetection/breast-cancer-early-detection-acs-recs

Centers for Disease Control and Prevention (CDC) What are the Risk Factors for Breast Cancer. (Retrieved February 12^th 2015): http://www.cdc.gov/cancer/breast/basic_info/risk_factors.htm

More patient information for this section is on this page.

Forward to 1B on screening results