Recently there have been numerous articles and publications debating on the efficacy of screening mammography. Researchers from World Health Organisation’s International Agency for Research on Cancer (IARC) found that women ages 50 to 69 who regularly receive mammography screening reduce their risk of dying from breast cancer by 40%, compared with women who are not screened. This translates into about eight deaths prevented per 1,000 women regularly screened, according to the group.
WHO’s IARC positions on mammography screening evidence
Method Strength of evidence
Reduces breast cancer mortality in women 50-69 Sufficient
Reduces breast cancer mortality in women 70-74 Sufficient
Reduces breast cancer mortality in women 40-49 Limited
Ultrasound plus mammography in women with dense breasts and negative mammography results
Reduces breast cancer mortality Inadequate
Increases cancer detection rate Limited
Mammography with tomosynthesis versus mammography alone
Reduces breast cancer mortality Inadequate
Increases detection rate of in situ and invasive cancers Sufficient
Increases detection of invasive cancers Limited
MRI plus mammography in high-risk women
Reduces breast cancer mortality in women with BRCA1 or BRCA2 mutation Inadequate
Increases detection rate of breast cancer in women with lobular carcinoma in situ or atypical proliferations Inadequate
Lancet reported recently that there is indeed a reduction in breast cancer mortality as a result of mammography screening in women who start getting exams at age 40 — at least in the first 10 years of follow-up, according to a new study in Lancet Oncology that followed women for 17 years. The study reports on the U.K. Age trial, which was designed specifically to examine the effect of mammography screening starting at age 40. The randomized controlled trial looked at breast cancer mortality and incidence at a median of 17.7 years of follow-up.
However a controversial French-led study published in the Journal of the Royal Society of Medicine (JRSM) on 7 July 2015, found screening mammography’s benefits have been overestimated due to unconventional statistical methods that differs from that used for other cancer screening trials. This was immediately countered by screening advocates who stressed that the authors of this study have ignored numerous publications proving the efficacy of screening.
To get more insight on breast cancer and on mammography screening, InfoMed met up with Dr. Sulaiman Tamanang, Consultant Radiologist and Nuclear Medicine Specialist at National Cancer Society Malaysia (NCSM).
Dr. Sulaiman Tamanang, MBBS, M.Med Radiology, M.Sc. Nuclear Medicine, after graduating from Universiti Malaya served at Ministry of Health Malaysia and subsequently joined the Medical Faculty of Universiti Kebangsaan Malaysia where he earned his M.Sc. in Radiology. He lectured until 1990 and then sub-specialised in Nuclear Medicine at the University of London. In 1998, Dr. Sulaiman joined NCSM as the Consultant Radiologist and Nuclear Medicine and currently sits on the Board of Directors of NCSM and he is also the Honorary Secretary of NCSM.
Excerpts from the interview with Dr. SulaimanTamanang………..
A woman’s breast contains different types of tissue, including fat. Women with dense breasts have relatively less fat in their breasts. Dense breasts have more glandular tissue that are suppose to produced milk.
Specifically, if more than 50 percent of your breasts is made up of glandular tissue (as opposed to fat), then by definition you are said to have “dense breasts.” It’s not uncommon that about 40 percent of women have dense breasts.
Breast density can be inherited and research has shown that dense breasts have a slightly increased chance of developing breast cancer — and dense breasts can make cancer harder to spot because both breast tissue and tumors appear white on a mammogram. And on the contrary, breast cancers (which look white like breast gland tissue) are easier to see on a mammogram when they’re surrounded by fatty tissue (which looks dark). This is the challenge to radiologists when trying to read the mammograms of a woman with dense breasts.
There are different modalities for breast screening and in September 2012, the FDA approved a new breast ultrasound system specifically for the breasts. This ultrasound scans the entire breast using high-frequency sound waves and quickly produces several images. This is usually recommended as an additional screening.
Then you have Magnetic resonance imaging (MRI) which uses magnets and radio waves to visualize the breasts. Study showed that MRI was better than mammography at finding ductal carcinoma in situ (DCIS) which is found in the milk duct where cancer started. This is considered Stage 0 or sometimes known as “precancerous” breast cancer and is non-invasive; which is hard to see on a routine mammogram screening. In the study about 90 percent of DCIS was found by MRI, while only 56 percent was detected by a mammogram. The American Cancer Society recommends using MRI only in certain cases for women at high risk for breast cancer. You cannot use MRI for routine screening because MRI is a very sensitive test that can lead to false alarms (suspicious breast abnormalities that are not breast cancer). MRI is also much more expensive than a mammogram. In future with greater understanding of the role of MRI for routine breast screening and with cost reduction, it could possibly be a replacement for mammogram.
Mammography is still the major screening modality for breast cancer. The imaging has progressed from 2Dfilm mammography to the latest 3D digital mammography, also known as tomosynthesis,whereby greatly reducing detection challenges associated with overlapping structures in the breast, which is the primary drawback of the conventional 2D. Thus, offering superior clinical performance for all breast types. Digital mammography sends X-ray images of the breast to a computer, rather than to film, making them easier to manipulate and interpret. A large study of nearly 50,000 women concluded that digital mammography was somewhat more accurate than regular film mammography in women with dense breasts.
Dr. Sulaiman says, “Most recently the 3D mammography has advanced further with the ability to reconstruct 2D images from the 3D data set using the C-View software”.
National Cancer Society Malaysia which was the first to acquire a 3D mammography in Malaysia recently upgraded it with the installation of the C-View software. InfoMed spoke with Dr. Sulaiman (NCSM) on this new clinical enhancement for breast screening.
InfoMed: How has 3D mammography also known as the breast tomosynthesis enhanced breast screening for cancer?
NCSM:The 3D mammography is a powerful, versatile screening tool that has transformed with significant improvements in breast cancer detection rates, reductions in recalls and better visualisation of breast structures. It has been shown to greatly reduce detection challenges associated with overlapping structures in the breast, which is the primary drawback of conventional 2D mammography.
InfoMed: Is 3D mammography the gold standard for breast cancer detection?
NCSM: The gold standard is still in doing a biopsy. Once we discover something suspicious in the screening with the 3D mammography which provides a clear, high resolution images, we can accurately and confidently get the patient to do a biopsy or dismiss a false positive.
InfoMed: How does the 3D mammography aid in resolving tissue superimposition when viewed as a 2D flat image?
NCSM: The 3D mammography reconstructs and separates breast tissue into thin cross sectional slices, so that the radiologist can see clearly what lies within the breast, free from the confusion of overlapping structures in the breast, which is the primary drawback of conventional 2D mammography.In the recent large study of tomosynthesis in breast cancer screening published in the Journal of the American Medical Association, the authors found a significant (41%) increase in the detection of invasive cancers with a simultaneous decrease in false positives.
InfoMed: What is combo-mode mammography?
NCSM: In the combo-mode both 2D digital mammography views and 3D views are acquired for each breast. The clinical advantages of the combo mode are clear; however the radiation exposure is higher from both the 2D and 3D exposure, albeit within allowable limits than for conventional 2D mammography.
InfoMed: How has technology pushed further the combo-mode mammography with the C-View software option?
NCSM: The tomosynthesis technology has been developed further with the C-View software option which generates 2D images from the (3D) tomosynthesis data without the need for a 2D exposure, reducing the patient’s radiation dose and time under compression. The 2D images created from the C-View software preserves important details from the tomosynthesis slices. The combined tomosynthesis and 2D exam with C-View software is superior to 2D alone for both fatty and dense breast types, improving diagnostic accuracy while reducing also reducing recalls.
InfoMed: What are the benefits of using the C-View software with the tomosynthesis?
NCSM: The C-View images plus 3D is superior to 2D mammography alone. Using the C-View software, the tomosynthesis acquisition and reconstruction is performed in the standard manner. It facilitates comparison to 2D priors, judging left/right asymmetry, and assessing the distributional aspects of calcifications. C-View images are never reviewed by themselves; they are reviewed along with the tomosynthesis images. Any potential finding in the C-View image is confirmed and evaluated in the 3D images before making a diagnosis, because the 3D images are the “fundamental” images in the study.
InfoMed: What are the advantages of doing the 3D mammography with C-View software?
NCSM: In addition to clearer visibility in some cases, there is absolutely no dose associated with C-View images. This allowsthe radiologist to have a full two-view 2D dataset as part of a two-view 3D study without any additional dose beyond the 3D images themselves. In addition, the compression time (without the 2D exposure) is shorter, which makes the patient happy.
Moreover, C-View images are an excellent replacement for 2D images, which is still essential for side-by-side comparison and evaluation of the overall configuration of a calcification cluster.
The National Cancer Society of Malaysia Giving Hope, Celebrating Life.
The National Cancer Society of Malaysia (NCSM) is the first cancer-related not-for-profit organization in Malaysia established in 1966 that provides an extensive range of cancer services and support to the public. It is a registered charity with tax exempt status under the laws of the Malaysian Societies Act and Registrar of Societies Malaysia. NCSM is proud to be an innovator and leader throughout its 49 years since its inception in 1966 with major accomplishments including being the:
a) First organisation that introduced pap smears into Malaysia in the early 1970s for the early detection of cervical cancer.
b) First health body that brought mammograms into Malaysia in 1985 for the early detection of breast cancer
c) First non-governmental centre offering nuclear medicine and radiotherapeutic services.
With support from the public and donations from philanthropists, NCSM is the only charitable organisation that provides a holistic cancer treatment and support to patients and caregivers – taking them through their journey in understanding and dealing with cancer in various phases including FREE mammograms services for Malaysian women aged 40 and above with household income below RM 10,000!
Interested to know more about NCSM and its services? Please contact 03- 2698 7300 or log on to www.cancer.org.my