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10 October 2020

Breast implants that are used for reconstruction or cosmetic augmentation can have either a smooth or textured surface, and plastic and reconstructive surgeons may prefer one or the other type of implant for various reasons. Last year, the US FDA recalled several types of textured implants manufactured by Allergan due to their link to breast implant-associated anaplastic large cell lymphoma (BIA-ALCL). BIA-ALCL is not thought to be associated with an increased risk of breast cancer, and is generally treated by removal of the implant and associated fibrous capsule (more information on BIA-ALCL and the FDA recall here).

A study recently published in JAMA Surgery* found that women who underwent post-mastectomy reconstruction using textured implants had a higher rate of breast cancer recurrence compared with those who had reconstruction performed with smooth implants.

The retrospective study was performed in South Korea, and evaluated the outcomes of 650 women (total of 687 implants) who underwent mastectomy and implant reconstruction for breast cancer, from 2011 – 2016. 413 of the implants were textured and 274 were smooth. Mean age was 43.5 and the majority of patients had early stage (I or II) breast cancer. 15% received postoperative radiation therapy and 44% received postoperative chemotherapy.

There were 28 breast cancer recurrences over the study period (4%). Local recurrences (in the chest wall area) were the same in both groups. 10 patients experienced distant recurrence (metastatic disease), and all had received textured implants. 

One cannot conclude from this study that the breast cancer recurrence was due to the textured implants, and limitations of the work include the retrospective nature. Larger, multi-institution studies are likely. In the meantime, it is reasonable for patients who are planning on implant reconstruction to discuss implant type, associated risks, and alternatives with their plastic surgeon.

*If you are not able to access the full study and would like a copy, please email me: contact at drattai dot com

19 December 2018

A study recently published in the Annals of Internal Medicine noted that breast cancer risk increases after childbirth, peaking at about 5 years after delivery. The increased risk was seen to persist for over 20 years.

The Annals study pooled the results from 15 prospective series. They found that in women with prior pregnancy, who had their most recent child 3 – 6.9 years before the study period, there were 41 excess breast cancer cases per 100,000 women at age 45, 170 excess cases per 100,000 at age 47.5, and 247 per 100,000 women at age 50. These numbers, while statistically significant, are relatively low. However, they may of course be considered important to an individual woman, deciding whether or not to have children. 

The authors discussed that proliferation of breast cells during pregnancy and the post-partum microenvironment may play roles in facilitating and promoting abnormal cellular proliferation and mutation. There was a protective (not preventative) effect of breast feeding. In addition, as this study conflicts with prior research noting a protective effect of pregnancy in terms of breast cancer development, the authors suggest that this protective effect may relate more to breast cancer that develops at the “peak ages” (after 60) rather than in younger women.

As this study was a pooled analysis of other studies, information on breast feeding was not available for all patients, there were some patients where it was not possible to distinguish if breast cancer developed during pregnancy or during the immediate postpartum period, and there was limited data on breast cancer subtypes.

The impact of pregnancy on recurrence risk in patients who have been treated for breast cancer is an area of active research. A 2013 study demonstrated that patients who became pregnant after being treated for an estrogen-receptor positive breast cancer did not have increased risks of cancer recurrence. In addition, there is an ongoing cooperative group clinical trial, the POSITIVE study, evaluating outcomes of women who have been treated for breast cancer and then interrupt endocrine therapy treatment for pregnancy.

My take-home points from the Annals study are that there seems to be an association (which is very different from cause and effect) between pregnancy and development of breast cancer at a young age, but the absolute number of increased breast cancer cases are relatively small. I do not think this study should discourage women from starting a family if they want to have children, and the authors have not recommended enhanced breast cancer screening for women who have been pregnant. All women are at risk for breast cancer, and pregnancy may increase short term risk. Of course, any new breast finding or change should be evaluated, whether a woman has had children or not. 

Additional Information:
HealthLine -Women Have Higher Risk of Breast Cancer After Childbirth
NY Times-Breast Cancer Risk May Rise After Childbirth, but is Still Low

31 January 2018

In women who undergo lumpectomy for breast cancer, the likelihood of another cancer developing in the treated breast can range from 0.2 – 1.0% per year, and this rate can be decreased with the addition of endocrine therapy such as tamoxifen or an aromatase inhibitor. The likelihood of developing a contralateral (opposite side) breast cancer is about 0.6% per year, and can also be reduced by endocrine therapy. Prior to making a decision on lumpectomy versus mastectomy, women commonly ask about the possible need for additional biopsies and procedures.

A study published in JAMA Surgery reviewed 2 large insurance databases to determine the frequency of breast biopsy after breast cancer treatment. Over 120,000 cases were analyzed. The researchers found that 15-23% of patients underwent subsequent biopsies during the 10 year period evaluated. 20-30% of these patients underwent additional cancer treatment.  Factors associated with lower biopsy rates included the use of endocrine therapy and older age. The use of partial breast irradiation (brachytherapy) was associated with a higher biopsy rate.

As this was an insurance claims database review (review of billing codes, not actual patient charts or medical records), it is not possible to know if biopsies were performed on the side of initial cancer or the opposite side, except in patients initially treated by mastectomy. In addition, a limitation of all claims database studies is that if the billing and diagnosis codes are not correctly entered, the information obtained will not be accurate. However, given the large number of claims reviewed, this study at least provides an estimate for patients to use when weighing the options of lumpectomy or mastectomy.

19 December 2017

Up to 70% of patients treated for breast cancer experience some degree of cognitive dysfunction (more commonly known as “chemobrain”) during and immediately after treatment, and the symptoms may persist in up to 15-25% of patients. The impact on quality of life and ability to work varies; patients may experience forgetfulness, challenges with multitasking, and difficulty finding words and may even struggle to learn new information. Older patients are more likely to be affected but any patient who has been treated with chemotherapy or even endocrine therapy may note changes in mental function. Multiple factors contribute to the development of cognitive dysfunction, including toxicity of the chemotherapy agents specific to the brain and nervous system as well as other medical conditions, genetic factors and aging. The diagram below is from a recent review in the Journal of Oncology Practice (Lange, Joly) and demonstrates the complex interactions:

Persistent cognitive impairment after treatment can have significant negative effects including reduced adherence to oral medications, diminished self-confidence, and negative impacts on personal and work relationships. It can be challenging, especially in older patients, to sort out which symptoms are related to treatment versus aging and possible neurologic disease.

Unfortunately, while there has been an awareness about treatment related cognitive impairment for some time (especially among patients!) this is a relatively new area for research. An editorial accompanying the Journal of Oncology Practice article (Vardy, Dhillon) notes that as the specific mechanisms by which cognitive dysfunction develop are not known, there are few evidence-based recommendations for prevention or treatment. In addition, studies often show little correlation between a patient’s subjective assessment of their cognitive function and performance on a standardized test designed to be more objective. Factors such as anxiety, depression, and fatigue are associated with (patient) perceived cognitive impairment, but are only weakly associated with objective measures of impairment.

Complicating matters further, the authors note that cognitive rehabilitation programs have been shown to improve subjective cognitive function, but the results are mixed regarding improvement in objective measures.

A second editorial (Baer) provided some practical guidance. The author recommended that physicians work with their patients to review and streamline medication lists, eliminating medications for anxiety, pain and sleep if no longer needed. Basic lifestyle patterns such as sleep habits and diet and exercise routines should be discussed. Patients should be encouraged to start a daily exercise program (with physical therapy referral if needed). Laboratory studies to assess for anemia, vitamin deficiencies and thyroid function should also be performed with corrective action taken if indicated. Coordination with the patient’s primary care physician should take place to ensure that other medical problems such as diabetes, hypertension, and sleep apnea are controlled as much as possible. If depression and/or significant anxiety are present, these need to be addressed and treated. Yoga and other meditative practices have also been suggested.

Additional research is certainly needed. In the meantime, patients should should realize first that the changes they are experiencing are real. Patients should be encouraged to discuss their symptoms and possible solutions with their treatment team.

The articles referenced above are behind a “paywall”. If anyone is interested in the full text article please feel free to email me: contact at drattai dot com and I will be happy to provide them.

10 November 2017

The American Society of Clinical Oncology (ASCO) has just released a statement on alcohol and cancer. They note that the importance of alcohol consumption as a contributor to cancer development is under appreciated, and that in the US, approximately 3.5% of all cancer deaths are related to alcohol intake. While the association between alcohol intake (especially heavy consumption) has been known for some time, this is the first formal statement from ASCO on the subject. Alcohol intake is most strongly linked to head and neck, esophageal, liver, colon and breast cancers.

Moderate drinking is defined as one alcoholic drink per day for women and two per day for men. The greatest risk appears to be in those who drink heavily, although there does not appear to be a “safe” level of intake. In a New York Times article, Dr. Clifford Hudis, the chief executive of ASCO, noted that “The more you drink, the higher the risk. It’s a pretty linear dose-response”. ASCO did not recommend that people stop drinking altogether, but they did suggest that more education for both oncology providers and the public is needed about the relationships between alcohol consumption and cancer.

Of course, people who never drink alcohol can still develop cancer, and some who are heavy drinkers will not. Alcohol intake is just one of many lifestyle factors that can contribute to increased risk. And as Aaron Carroll writes, also in the New York Times, “maybe any increase in risk is too much for you”. If you do drink, I recommend that women limit their alcohol intake to 3-6 drinks per week – and don’t save up your weekly allowance for Friday or Saturday night! I think Dr. Carroll’s conclusion stated it best: “The absolute risks of light and moderate drinking are small, while many people derive pleasure from the occasional cocktail or glass of wine. It’s perfectly reasonable even if a risk exists — and the overall risk is debatable — to decide that the quality of life gained from that drink is greater than the potential harms it entails.”

27 September 2017

3D mammography, also known as tomosynthesis, is becoming more widely available. The thin “slices” (images) make it easier to spot cancers in patients with dense breast tissue. In addition, the use of 3D mammography can decrease the rate of “callbacks” – additional images that are often recommended after a screening mammogram due to uncertainty about the findings. Callbacks are more common in women with dense breast tissue. One concern about tomosynthesis is that it might find too much – not everything that is found will be dangerous, and this can result in over diagnosis and over treatment. In addition, a slightly higher dose of radiation exposure is required with 3D imaging in some facilities.

In 2005, the DMIST trial results were published in the New England Journal of Medicine – this study compared the older film screen mammography to digital mammography and found that digital mammograms were more accurate for women under the age of 50, women with dense breast tissue, and those who were pre- or peri-menopausal. Digital mammograms are now standard across most of the country.

The TMIST (Tomosynthesis Mammographic Imaging Screening Trial) trial will compare 3D mammography 2D digital mammography. Rates of cancer detection, callbacks, and procedures (such as biopsies) will be monitored. In addition to evaluating the performance of the imaging technology, the study will attempt to identify biological factors associated with breast cancer risk – patients who participate in the study will be asked to provide a buccal (cheek) swab and blood sample.

The study plans to enroll approximately 165,000 women at approximately 100 centers across the country. Additional information about the study and participating centers is available at the following sites:

National Cancer Institute
ECOG-ACRIN (cooperative group sponsoring the trial)
ClinicalTrials.gov

 

8 May 2017

As a past-president of the American Society of Breast Surgeons I am probably more than a little biased. However, as always, the annual meeting held April 26-30th in Las Vegas was terrific. Topics including the full spectrum of breast disease, including benign and high risk lesions, genetic testing, breast cancer diagnosis and treatment including medical and radiation oncology updates, and metastatic disease.

The press briefing highlighted 3 abstracts which showed that:

  • Modern therapy for inflammatory breast cancer is associated with better outcomes than historically seen
  • Post-treatment lymphedema is related to a combination of treatments including surgery, radiation therapy, and chemotherapy – not just from surgery
  • Patients with DCIS have a 5 year risk of developing a cancer in the other breast of 2.8% and a 10 year risk of 5.6%, and patients should be discouraged from undergoing bilateral mastectomy for this condition. Developing a new cancer in the previously treated breast was twice as likely as developing a new cancer in the opposite breast, and the use of tamoxifen reduced the likelihood of any recurrence.

Dr. Nathalie Johnson moderated a pre-meeting course on Building a Breast Cancer Survivorship Program. I was invited to speak on Traditional Versus Virtual – Options for Patient Support and Education. Just as it can be challenging to choose between cake and ice cream (2 really good things), patients note advantages to both in person and online support and education. It doesn’t have to be one or the other – do what works for YOU! My slides are posted on SlideShare.

During the general sessions, a few topics stood out to me:

Dr. Shelley Hwang from Duke University spoke on DCIS subtyping and overtreatment. She noted that DCIS now comprises over 20% of all mammographically detected breast cancer. It is considered a “non-obligate precursor” of invasive cancer – the rate and likelihood of progression to invasive cancer are not clearly known. However, it is clear that some patients will never exhibit progression to invasive disease, and she discussed this in the context of thyroid and prostate cancer – two situations where we know that treatment in some patients will not provide the patient any benefit. The challenge is to sort out which patients will benefit from treatment and which ones will not. The COMET study is currently enrolling patients with low grade DCIS to in an attempt to help answer these questions.

Dr. Virginia Herrmann from Washington University in St. Louis spoke on non-genetic breast cancer risk factors. This is an important topic and I believe one that doesn’t get covered enough. She noted that hormone replacement therapy does increase risk – although the incremental risk is small and is seen only after about 5 years of use. However, longer term use does result in higher risk. Increased body mass index (BMI) is associated with risk – the risk of breast cancer is 30% higher in patients with a BMI greater than 31 kg/m2 compared to a BMI of 20 kg/m2. She noted that there is a linear relationship between alcohol intake and cancer risk, noting a 10% increase in risk for each 10 gm/day (for wine this is a little over 3 oz) increment in alcohol consumption. The risk is most associated with post-menopausal breast cancer, although in the study she quoted, only alcohol intake during age 50s was associated with an increased risk of postmenopausal breast cancer. She noted the association of ionizing radiation and breast cancer, and young women who received mantle (chest area) radiation for Hodgkin’s lymphoma have a markedly increased risk for developing breast cancer. She noted that breast cancer risk is increased in smokers, correlated with smoking intensity and duration. Finally, she noted the increased risk of breast cancer among soldiers stationed at Camp LeJune related to contaminated drinking water (tetrachloroethylene and trichloroethylene).

Dr. Tiffany Traina, a Memorial Sloan Kettering medical oncologist, gave a brief presentation about triple negative breast cancer: Searching For the Magic Bullet. There are several promising treatment strategies including targeting androgen receptors, the use of PARP-inhibitors in patients who have BRCA gene mutations, antibody-drug conjugates, immune modulating approaches, and targeted therapies based on tumor genomic profiles. Stay tuned – much more to come over the next few years related to this aggressive breast cancer subtype.

Dr. Lisa Newman, from the Henry Ford Health System in Detroit, spoke on Breast Cancer Outcomes: Disparities versus Biology. I have heard her speak on this topic multiple times over the years and always enjoy her excellent presentations. She noted that the incidence of breast cancer in black women is increasing, now close to that in white women. However, mortality rates for black women are higher than those for white women. There is an increased frequency of triple negative breast cancer in black women. She is involved in a research initiative evaluating the association between African ancestry and high risk breast cancer in white American women, African American women, and women in Ghana, including studying novel aspects of tumor biology and breast cancer stem cells – she is asking the question “are there differences in the oncogenic potential of mammary tissue that are associated with ancestry”? She concluded with what I felt was a powerful slide – 60% – 43% – 20%. Those were the survival rates for passengers on the Titanic who were in 1st – 2nd – 3rd class. She noted that healthcare outcomes are often dependent on access to care, and ended with a quote from Dr. Martin Luther King, Jr.: “Of all the forms of injustice, inequality in health care is the most shocking and inhumane”.

Dr. Stephen Edge, from the Roswell Park Cancer Institute, gave an update on the new American Joint Commission on Cancer staging system (AJCC 8th edition). Currently we stage breast cancer based on tumor size and lymph node status. However, it is recognized that that tumor biology plays an important role in prognosis and in some patients it may be more important that tumor size. The new staging system will incorporate tumor grade, Her2/neu status, ER/PR status, and Oncotype Dx status (if available) and should more accurately reflect prognosis. There are 422 lines in the new staging system – it will be impossible to memorize! Thankfully, he noted that the AJCC is working on a staging app.

The last day of the meeting held some great sessions, and the meeting room remained packed up until the very last minute. Dr. Ann Partridge from Dana Farber discussed special considerations in the young breast cancer patient. She noted that the disease is different, the patients are different, and the treatments should be different. Younger women have a higher likelihood to have more aggressive subtypes such as Her2/neu over-expressed and triple negative, and have lower survival rates than older women – even in those with the ER positive breast cancer. However, she cautioned not to over-treat patients based only on age. She noted that young age is not a contraindication for breast conservation, and that there is no clear improvement in mortality in patients who undergo more extensive surgery. She noted the need for improvements in treatment and support, including focused research and guidelines, which should lead to better outcomes.

Dr. Irene Wapnir from Stanford spoke on fertility preservation issues. She noted the various fertility options including medications and procedures. She also reviewed the POSITIVE trial, which will be assessing the risk of breast cancer relapse in patients who temporarily stop endocrine therapy to permit pregnancy, as well as to evaluate factors associated with successful pregnancy after interruption of endocrine therapy. She also stressed that fertility preservation should be discussed with any woman of childbearing age, whether or not she has had a prior pregnancy or a child – physicians won’t know what is important to their patients unless we ask!

Dr. Katherina Zabicki Calvillo from Dana Farber discussed breast cancer in pregnancy. She noted that 0.2-4.0% of breast cancers are diagnosed in pregnant patients – about 1 in 3000 pregnancies. She also noted that given the overall delay in childbearing (and the association of increasing age with breast cancer), the incidence of pregnancy-associated breast cancer will increase. Delays in diagnosis are related to hormonal changes which affect breast tissue making the exam more challenging, and that many patients and physicians assume that masses are related to pregnancy. She stressed that pregnancy termination is usually NOT required, but a multidisciplinary team approach is required. Many of these patients present in more advanced stages, but stage-for-stage, the prognosis is similar to non-pregnant patients with breast cancer. Chemotherapy can be given after the first trimester, but hormonal and Her2/neu targeted therapy should be avoided. She noted that mastectomy should be performed in the first and early 2nd trimester, and discussed the challenges of immediate reconstruction. Breast conservation could be considered in the late 2nd or 3rd trimester with post-lumpectomy radiation planned for after delivery.

Dr. Kevin Hughes from the Massachusetts General Hospital reviewed research studies that have found that in women over the age of 70 with early stage breast cancer, radiation therapy after lumpectomy may not be necessary.  The CALGB 9343 study showed that survival rates were the same whether women received radiation therapy or not. Radiation therapy did reduce the likelihood of cancer returning in the breast (local recurrence) from about 4% in the untreated patients to about 1% in the treated patients (after 5 years of follow up). However it is important to realize that the majority of women in that study were treated with endocrine therapy, which can help reduce the risk of local recurrence. As with many decisions regarding breast cancer treatment, a careful discussion of the risks and benefits of each option is necessary.

Dr. Tina Hieken from the Mayo Clinic gave a very interesting talk on the microbiome and the impact on breast cancer. We normally co-exist with many bacteria – we have ten times the more microbial cells compared to human cells. These microbes carry out metabolic reactions that can be essential to human health. The genetic material (genome) of our microorganisms is called the microbiome. She and her colleagues studied breast tissue from women with and without breast cancer and found that the background breast microbiome is different in women with breast cancer compared to those with benign conditions. She concluded by noting that the future may involve using a microbial pattern to predict breast cancer risk, exploiting the microbiome to enhance treatment response, and that there may also be implications for a cancer prevention vaccine. The Washington Post recently covered her research – definitely worth a read for more information.

Dr. Anthony Lucci from MD Anderson discussed the “Ongoing Saga of Circulating Tumor Cells”. We would all like to see the day when a blood test can tell us with certainty if cancer has developed or returned – but we’re not there yet. After reviewing several studies evaluating both circulating tumor cells (CTC) and circulating “cell free” DNA, he concluded that this information does provide prognostic information in both metastatic and non-metastatic patients, but is not in the current ASCO or NCCN guidelines for guiding treatment. Combining the CTC status with response to preoperative chemotherapy may identify a low risk subset of patients, but noted that additional studies are needed before we can reach the ultimate goal which is improving outcomes by monitoring and responding to CTC and cell free DNA levels.

Dr. Manjeet Chadha from Mount Sinai spoke on repeat lumpectomy after prior lumpectomy and breast radiation. Traditionally, mastectomy has been recommended if cancer returns after lumpectomy and radiation therapy. On average, there is about a 10% risk of “in breast” recurrence after lumpectomy and radiation, but this will vary based on tumor and treatment type. She reviewed several studies evaluating the different types of focused or partial breast radiation that may be used in selected patients who experience recurrence of their breast cancer. She also called for additional studies in this area.

One of the last talks was by Dr. Mehra Golshan from Dana Farber. He spoke about the decision whether or not to operate on patients with breast cancer who present with Stage IV (metastatic) disease. Traditionally, we have not recommended surgery for patients with metastatic breast cancer as these patients were not expected to have long survival, and it was not felt that removal of the main tumor would impact survival. Evaluating existing studies has also been challenging because while some have shown a benefit to removal of the main tumor, the patients who underwent surgery in those studies tended to be younger and healthier. He concluded by noting that surgery in patients with Stage IV breast cancer is not standard of care, but some studies do support this practice. It is recommended that these patients be evaluated in a multidisciplinary forum and that treatment choices be individualized.

 I returned from the meeting exhausted but energized. In addition to the scientific content, the meeting is an opportunity to connect with friends and colleagues across the country. I’m already looking forward to ASBrS 2018!

This post has not been endorsed by the American Society of Breast Surgeons.

25 August 2016

A study published today in the New England Journal of Medicine reports on the 5 year results of the MINDACT (Microarray In Node-negative and 1 to 3 positive lymph node Disease may Avoid ChemoTherapy) trial. This study was designed to evaluate the use of a tumor gene signature test (MammaPrint) compared with standard factors to assess the need for chemotherapy.

This study enrolled 6693 women in 112 countries who had undergone surgery for Stage I and II breast cancer. Once patients were registered, they were stratified based on risk. Risk was assessed both by the MammaPrint (MP) score as well as standard clinical – pathological markers (CP) such as tumor size, grade, ER/PR status, and Her2/neu expression calculated using the Adjuvant! Online tool.

2745 patients who had low risk MP and CP scores did not receive chemotherapy; 5 year metastasis-free survival in this group was approximately 97.6%. These findings were consistent with those reported using a different genomic test, the Oncotype Dx test, which also demonstrated good results without chemotherapy in low risk patients. 1806 patients who were high risk by both assessments received chemotherapy and 5 year metastasis-free survival in this group was approximately 90.6%.

The other 2 groups were those with discordant results, and these patients were randomized to either chemotherapy / endocrine therapy or endocrine therapy. The results for the 592 patients with high risk MP scores but low risk CP assessment are pending. The recently published study focuses on the 1550 patients with low risk MP scores but were high risk based on CP assessment.

The study demonstrated that in these patients, chemotherapy provided a slight benefit: 1.5% improvement in survival without metastatic disease, 1.4% improvement in overall survival, and 2.8% improvement in disease free survival. The study was not powered or designed to determine if these differences were statistically significant.

On the surface, the study seems to indicate that chemotherapy is of little to no benefit for those patients with low risk MP scores and high risk CP features. There is no question that genomic tests such as the MammaPrint have revolutionized our treatment recommendations. We now have the ability to obtain more detailed information about an individual patient’s tumor biology, which can help us guide treatment decisions. It is clear that our traditional methods of assigning risk such as tumor size, grade, and node status, do not always tell the whole story, and it is no longer acceptable to recommend chemotherapy “just to be sure”. The use of genomic tests in appropriate patients is very important to avoid the real dangers of over treatment. But as this study was not designed to assess statistical significance (rather, “non inferiority“), can we say that the benefits demonstrated from chemotherapy may not be important for an individual patient?

Median follow up in this study was was 5 years. 48% of patients were lymph node positive, 93% had grade 2 or 3 disease, and 34% were age 50 or younger. These factors are more often associated with an earlier risk of recurrence, so 5 years may be sufficient to note a difference in survival rates. It was also stated by the authors that “adjuvant chemotherapy exerts most of its beneficial effects early in the course of the disease”. However, they also noted that many of the tumors were ER+, which may recur well past 5 years. 10 year follow up is planned.

In an accompanying editorial, Drs. Hudis and Dickler point out that “although we may all agree that a 1% risk of distant metastasis at 5 years on the basis of genomic testing eliminates any potential benefit of chemotherapy, at what point would we begin to have differing opinions and perhaps mixed results from clinical trials? Answering this question is even more challenging, given that all chemotherapy is not the same in terms of efficacy or toxicity and that patients and health care providers bring subjectivity and personal values to their treatment decisions.”

As was pointed out during a recent online exchange (by a woman who had a low recurrence score and now has metastatic disease), these tests are not guarantees. While the numbers are low, some women in the low risk group developed metastatic disease. It is not known if chemotherapy would have been of benefit, but it does demonstrate how percentages are applicable to populations, not necessarily to individuals. We do not yet have a test that will predict the outcome with 100% certainty. The test results should be presented as part of a discussion which includes the patient’s preferences, values and concerns – concerns regarding cancer recurrence as well as potential side effects of therapy.

23 August 2016

A study published in the Annals of Internal Medicine evaluated screening mammography taking into account breast density and breast cancer risk. For women age 50-74, the conclusion of the authors was that for women of average risk with low breast density (fatty or scattered fibroglandular), triennial (every 3 year) mammography screening averted the same number of breast cancer deaths as annual or biennial screening. Women screened every 3 years also had lower rates of biopsy procedures. For women at high risk with high breast density (heterogeneously or extremely dense), annual screening was better. High risk / high density patients accounted for approximately 1% of the study population.

The study was funded by the National Cancer Institute. The authors used simulation modeling which included national breast cancer incidence, breast density, and screening performance data. They did not include patients with genetic abnormalities such as BRCA 1/2 mutations. They also did not take into account the impact of MRI or tomosynthesis / 3D mammography.

Risk assessment involves a calculation (using various models) which takes into account a woman’s age, body mass index, menstrual and reproductive history, family history, prior biopsies, and other factors known to influence the risk of breast cancer development. In the current study, the authors used a risk calculator that takes into account breast density. Breast density is a factor associated with breast cancer, although studies vary regarding the impact of density on risk. Adding to the confusion, breast density rating is subjective – different radiologists may assign different density scores to the same patient. The model used in the current study also takes into account factors such as improved detection using digital mammography, improved treatment effectiveness, and the usual decrease in breast density that is seen with increasing age. It is unclear at this time which is the “best” risk assessment model to use – all have limitations, some significantly over-estimate risk, and none are a “crystal ball”.

So what should women do? The ideal screening test is one that is inexpensive, readily available and safe. It should also find cancers early enough to make a difference. Mammograms are an imperfect tool but they perform reasonably well in a wide variety of settings. The ideal screening program is to tailor the technology and screening frequency to the patient’s risk – one size never fits all. Women should be aware of their family history and risk factors, ask about their breast density, and then discuss these factors as well as their personal preferences regarding breast cancer screening with their physicians. True individualized and personalized risk-based screening is not yet a reality, but by making recommendations based on risk, we are taking steps in the right direction.

An Oklahoma mayor underwent a 3D mammogram (tomosynthesis) as part of a hospital promotion. She was diagnosed with ductal carcinoma in-situ (DCIS, also known as Stage 0 breast cancer) and she stated that the study “…saved my life.” She also recommended that women make sure to obtain a 3D mammogram. The story noted that tomosynthesis “virtually eliminates” the need for additional testing, and that early detection makes it less likely that the patient will need to undergo chemotherapy or radiation.

Here are a few errors in the story:

Statement: the mammogram saved my life
Fact: survival from breast cancer depends on many factors. The survival rate for patients with DCIS, regardless of treatment, is close to 97%. For invasive cancers, survival rates depend on stage as well as tumor biology. Small breast cancers “caught early” can still be lethal. It’s not the cancer in the breast that kills, it’s the cancer that gets to other areas of the body. Small tumors can and do spread.

Statement: early detection makes it less likely that a patient will need chemotherapy
Fact: the need for chemotherapy depends on tumor stage as well as tumor biology. As noted above, some very small, early stage breast cancers are very aggressive and have a high likelihood of spread, so chemotherapy is recommended. This is especially true for “triple negative” and “Her2/neu over-expressed” breast cancer subtypes.

Statement: early detection makes it less likely that a patient will need radiation therapy
Fact: radiation therapy is a standard recommendation for women with early stage breast cancer who undergo a lumpectomy. Since most women with early stage breast cancer are candidates for a lumpectomy, this statement simply doesn’t make any sense.

Statement: tomosynthesis “virtually eliminates” the need for additional imaging
Fact: while tomosynthesis can reduce the likelihood of needing additional views (“callback”) especially in women with dense breast tissue, diagnostic imaging with possible biopsy are still recommended when a concerning abnormality is seen.

While I certainly wish Ms. Noble well, stories like this always make me cringe, because they over-simplify a very complex situation. Here are some posts from Health News Review with some additional information:
Mayor: 3D Mammogram Saved My Life
3D Mammography and False Hope