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Published letters
Displaying 1-10 letters out of 2273 published
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Mammography Screening Guidelines
Submit responseTO THE EDITOR: In their recent evaluation of mammography, the US Preventive Services Task Force recommends screening for breast cancer bi- annually starting at age 50 (1). The Task Force has stressed that this recommendation depends solely on the trade-off between medical benefits and harms, with no consideration of costs. Editorials in both the Wall Street Journal (2) and the New England Journal of Medicine (3), however, suggest that the recommendation was in fact motivated by cost considerations. A careful examination of the data analyses by Mandelblatt et al. (4), presented in support of the recommendations, would appear to confirm the view that costs were indeed pivotal in informing the Task Force recommendation.
The Task Force states that its recommendation involves trading off the mortality benefit of screening against medical "harms" such as provoked anxiety, the adverse consequences of false positive tests including unnecessary biopsies and treatment, and the adverse effects of "over-diagnosis". But how did they use the evidence about these effects to reach their recommendation? There are no analyses in the report nor in the supporting articles (4,5) that simultaneously consider both benefits and harms and that lead directly to the specific recommendation to begin screening at age 50, and to do it bi-annually. The only analysis provided that aligns clearly with the Task Force recommendation is the analysis displayed in the Figure in Mandelblatt et al. (4) This Figure presents the results from independent analyses by six investigative groups of the projected mortality reduction for a range of screening strategies, covering various starting ages, and including options to screen annually or bi-annually. The critical feature of these analyses is that the population mortality benefit is contrasted solely with the numbers of mammograms required, a surrogate for resource utilization, and thus for costs. The authors do not utilize "harms". These analyses search for an optimal strategy at the point where the graphs plateau, representing a point of diminishing returns from additional screening. Bi-annual screening strategies starting at age 50 are close to the "optimal" inflection point in all 6 of these analyses, and this would appear to be the crucial finding that motivated the Task Force recommendation. The number of mammograms in these analyses does not represent "harm". Rather, it is a measure of the societal investment in mammography, i.e. the societal cost. In other words, this is, in effect, a thinly disguised assessment of cost relative to effectiveness, something most experts would label a cost-effectiveness analysis.
References
1. US Preventive Services Task Force. Screening for breast cancer: US Preventive Services Task Force recommendation statement. Ann Intern Med. 2009;151:716-26. PubMed PMID: 19920272.
2. Editorial. Liberals and mammography: Rationing? What rationing? Wall Street Journal 2009, November 24 [cited 2009 December 2]. Available from: http://online.wsj.com/public/search/page/3_0466.html?KEYWORDS=liberals%20and%20mammography&mod=DNH_S
3. Truog RD. Screening mammography and the "R" word. N Engl J Med. Epub 2009 Nov 25. doi: 10.1056/NEJMp0911447; PubMed PMID: 19940292.
4. Mandelblatt JS, Cronin KA, Bailey S, Berry DA, de Koning HJ, Draisma G, et al. Effects of mammography screening under different screening schedules: model estimates of potential harms and benefits. Ann Intern Med. 2009;151:738-47. PubMed PMID: 19920274.
5. Nelson HD, Tyne K, Naik A, Bougatsos C, Chan BK, Humphrey L. Screening for breast cancer: an update for the US Preventive Services Task Force. Ann Intern Med. 2009;151:727-37.
Conflict of Interest:
None declared
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Dialysis in Pandemic Influenza
Submit responseTO THE EDITOR: The 2009 swine-origin Influenza A (H1N1) pandemic highlighted the importance of identifying public health measures to mitigate influenza virus transmission. <P> Cowling BJ suggested that hand hygiene and facemasks can reduce influenza virus transmission if implemented early after symptom onset in an index patient. During a pandemic, resources may not be available to isolate all infected individuals, and home isolation of some patients may be required (1).
Patients with ESRD are compromised hosts CDC recommended that HD patients should wear a surgical mask and be placed in a separate room for dialysis with the door closed. The continuation of hemodialysis (HD) and peritoneal dialysis (PD) undergoes a large limitation. Especially, in HD, both infected and uninfected dialysis is taken care of within a center. To avoid in-center infection, we may need to dialyze infected patients in large institution and dialyze the patients who are uninfected in the small institution. On the other hand, the peritoneal dialysis has a large merit because it is possible to dialyze at home even during pandemic, but in certain areas, supply shortage due to logistic difficultymay become disadvantage. In the United States the number of HD patients is 327,754 and the number of PD patients is 26,082 and the number of HD patients in Europe is nearly 290,000, and the number of PD patients is 38,274 (2). In Japan, the number of HD patients is 265,620 and the number of PD patients is 9,314. <P> The HD/PD combination therapy, which comprises 5 or 6 days of PD combined with 1 HD session per week, is performed in Japan to better control body fluid and remove solute (Fig.1). We (Jikei University School of Medicine, Kashiwa Hospital) started the HD/PD combination therapy in 1990 and approximately 1800 patients (20% of all PD patients) in Japan undergo HD/PD combination therapy (3). The HD/PD combination therapy is a modality which allows patient to choose from both PD and HD during influenza pandemic. This is a large merit of the HD/PD combination therapy. We should review a dialysis modality from a viewpoint that which treatment option is optimal when disaster occurs such as earthquakes as well as influenza pandemic.
References
1. Cowling BJ, Chan KH, Fang VJ, Cheng CK, Fung RO, Wai W, Sin J, Seto WH, Yung R, Chu DW, Chiu BC, Lee PW, Chiu MC, Lee HC, Uyeki TM, Houck PM, Peiris JS, Leung GM. Facemasks and hand hygiene to prevent influenza transmission in households: a cluster randomized trial. Ann Intern Med. 2009;151:437-46.
2. USRDS. 2008 annual data report: Atlas of chronic kidney disease & end-stage renal disease in the United States. Am J Kidney Dis. 2009; 53(1, Suppl. 1).
3. Kawanishi H, Hashimoto Y, Nakamoto H et al. Combination therapy with peritoneal dialysis and hemodialysis. Perit Dial Int 2006; 26: 150-154.
Conflict of Interest:
None declared
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Re:The 40-50 age group.
Submit responseI can not believe this is happening!! We have come so far with our outreach to women everywhere to encourage them and assure them that early detection was the best protection to keep from dying with breast cancer. I have been a mammographer for 15 years and I have too many memories of young women in their 40's being diagnosed with breast cancer. If these women waited to come in when they were 50 the cancer could have spread to their lymph nodes and would be more complex to treat. I don't know what these people were thinking when they came out with this recommendation. Mammographers need to continue to encourage women not to wait until their 50 to get a mammogram.
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Cost of preventing one breast cancer death for women in their 40's
Submit responseThe Editor Annals of Internal Medicine
Dear Editor,
The US Preventive Service Task Force (USPSTF) revised recommendations on mammography have understandably stirred fierce debate. The research cited by USPSTF in support of their recommendation for women in their 40's seems compelling.
We assume in our calculation that the average cost of a mammogram is $250, about 1% of those screened will need a biopsy at an average cost of $1,000, and about 10% will need some other less expensive testing. If indeed 1,900 women in their 40's have to be screened annually for a decade to avert one breast cancer death, the associated cost comes to approximately $5 million.
The USPSTF revised guidelines recommend against performing mammography on women in their 40's on a population basis. However, for those in their 40's at high risk, they recommend mammography on a case by case basis in consultation with the physician.
Every penny of the $5 million will be well-spent if the one breast cancer death averted is of my 45-year old daughter with no known risk factor. That is where the debate gets personal and emotional- an area where science, data, and analyses become irrelevant. And, that is where the debate gets political, seemingly making all the science, all the data, and all the analyses irrelevant.
Somewhere, somehow, someone must find a middle ground so we as a society can make efficacious use of a viable early detection method for averting breast cancer deaths. It also behooves us as a society to look into other ways to avert breast cancer deaths, such as primary prevention using dietary modification. Perhaps the policy makers in addition to early detection can play a proactive role in prevention, providing a multi- pronged strategy to fight breast cancer mortality.
Conflict of Interest:
None declared
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Article on disparities in control of cardiovascular disease and diabetes raises several measurement issues
Submit responseMcWilliams et al.(1) analyze changes in disparities in dichotomous and continuous measures of control of cardiovascular disease and diabetes from 1999 to 2006 and the effects of Medicare coverage on these disparities. Three aspect of their analysis warrant comment.
First, the authors analyze the size of disparities in control rates in terms of absolute differences between rates. The analysis is flawed for failure to consider the way absolute differences between outcome rates tend to change solely because of changes in the overall prevalence of the outcome -- as I have discussed with respect to similar flaws in the references nos. 8, 11, and 20-22 of the article ([2-7). See also Houweling et al. (8), which similarly recognizes the patterns of correlations between absolute differences and the overall prevalence of an outcome and the need to consider overall prevalence in appraising the meaning of standard measures of differences between outcome rates. For research of this nature to be of value, it is necessary to appraise disparities between outcome rates in terms of measures that are unaffected by the overall prevalence of the outcome, such as that described in references 9 and 10, which derives differences between means of underlying risk distributions based on outcome rates (9,10).
But, in any case, it is not useful to analyze disparities in terms of absolute difference or other measures of differences between outcome rates that are affected by the prevalence of the outcome without even addressing the measurement issues. Notably, in observing that they are building on further work that found persistent or widening healthcare disparities in recent years, the authors cite the National Healthcare Disparities Report. But the National Healthcare Disparities Report not only relies on relative differences between rates rather than absolute differences, but relies on whichever relative difference (in the favorable or the adverse outcome) is the larger. Thus, as explained in references 2, 6, and 7 (and their corrections), as well as 10-12, with regard to the appraisal of the directions of changes in the size of disparities over time, the approach of the National Healthcare Disparities Report tends toward reaching exactly the opposite conclusions of those reached by researchers who rely on absolute differences (allowing, of course, that meaningful changes may counter the patterns that are solely statistically driven)(10-12).
Second, the authors also analyze the size of disparities in terms of continuous measures, including differences between average systolic blood pressure levels and average hemoglobin A1c levels. Such an approach may well avoid the problems associated with the ways that absolute differences and other standard measures of differences between outcome rates tend to be affected by the overall prevalence of an outcome. Where available data permit, such an approach -- making use, as it does, of the actual distributions of risk factors rather than a derived difference between means of a hypothetical risk distribution -- may well be much superior to the approach discussed in references 9 and 10.
But the most useful way to measure differences between means is by deriving an effect size from the arithmetic difference between means divided by the standard deviation (either the pooled standard deviation or that of one group or the other). The authors instead simply discuss the changes in terms of changes in the arithmetic differences between means. The authors highlight what they term a "0.7%" reduction in the race or ethnic difference and a "0.5%" reduction in the education difference for subjects over 65 compared with those under 65. The former reduction was from an absolute difference between mean levels of 0.9 percentage points to one of 0.2 percentage points; the latter was from 0.6 percentage points to 0.1 percentage points. Thus, allowing that the standard deviation serving as the denominator in the effect size fractions may differ somewhat for the 45 to 64 group and the over-65 group (NHANES 2005 data, which happen to be at hand, show a standard deviation of 1.23 for the former group and 0.94 for the latter group), these figures suggest a very substantial reduction in the disparity. The magnitude of such reduction is hardly reflected in the "0.7%" and "0.5%" figures used by the authors, even if such figures reflect valid measures.
Third, while the authors generally rely on percentage point difference and percentage point changes in figures, they almost invariably describe an "x percentage point" change as an "x%" change. Whether or not the latter usage is even technically correct, most readers regard an "x%" change as a percentage change not a percentage point change. The authors themselves in endeavoring to be clear in their discussion of the implications of differential increases in insurance coverage refer to a "6.6 percentage point" difference in increases in coverage rates. The entire article would be much clearer if discussion of absolute differences between percents were invariably described as percentage point differences rather than percent differences (13).
References:
1. McWilliams JM, Meara E., Zaslavsky AM, Ayanian JZ. Differences in control of cardiovascular disease and diabetes by race, ethnicity, and education, U.S. trends from 1999 to 2006 and effects of Medicare coverage. Ann Int Med. 2009;150:505-515.
2. Scanlan JP. Effects of choice measure on determination of whether health care disparities are increasing or decreasing. Journal Review May 1, 2007 (responding to Trivedi AN, Zaslavsky AM, Schneider EC, Ayanian JZ. Trends in the quality of care and racial disparities in Medicare managed care. N Engl J Med 2005;353:692-700, and two other articles in the same issue): http://journalreview.org/v2/articles/view/16107620.html
3. Scanlan JP. Understanding patterns of absolute differences in vaccination rates in different settings. Journal Review Apr. 22, 2008 (responding to Schneider EC, Cleary PD, Zaslavsky AM, Epstein AM. Racial disparity in influenza vaccination: Does managed care narrow the gap between blacks and whites? JAMA 2001;286:1455-1460): http://journalreview.org/v2/articles/view/11572737.html
4. Scanlan JP. First learn to measure healthcare disparities. Health Affairs Mar. 12, 2008 (responding to Casalino LP, Elster A, Eisenberg A, et al. Will pay-for-performance and quality reporting affect health care disparities? Health Affairs 2007;26(3):405-414):: http://content.healthaffairs.org/cgi/eletters/26/3/w405
5. Scanlan JP. Inclusion of healthcare disparities issues in pay-for -performance programs should await development of reliable means of measuring changes in disparities over time. Journal Review Feb. 16, 2008 (responding to Casalino LP, Elster A, Eisenberg A, et al. Will pay-for- performance and quality reporting affect health care disparities? Health Affairs 2007;26(3):405-414): http://journalreview.org/v2/articles/view/17426053.html
6. Scanlan JP. Understanding the ways improvements in quality affect different measures of disparities in healthcare outcomes regardless of meaningful changes in the relationships between two distributions of factors associated with the outcome. Journal Review Aug. 30, 2007 (responding to Sequist TD, Adams AS, Zhang F, Ross-Degnan D, Ayanian JZ. The effect of quality improvement on racial disparities in diabetes care. Arch Intern Med 2006;166:675-681): http://journalreview.org/v2/articles/view/16567608.html
7. Scanlan JP. Understanding patterns of correlations between plan quality and different measures of healthcare disparities. Journal Review Aug. 30, 2007 (responding to Trivedi AN, Zaslavsky AM, Schneider EC, Ayanian JZ. Relationship between quality of care and racial disparities in Medicare health plans. JAMA 2006;296:1998-2004):: http://journalreview.org/v2/articles/view/17062863.html
8. Houweling TAJ, Kunst AE, Huisman M, Mackenbach JP. Using relative and absolute measures for monitoring health inequalities: experiences from cross-national analyses on maternal and child health. International Journal for Equity in Health 2007;6:15: http://www.equityhealthj.com/content/6/1/15
9. Solutions sub-page of Measuring Health Disparities page of jpscanlan.com http://www.jpscanlan.com/measuringhealthdisp/solutions.html
10. Can We Actually Measure Health Disparities?, presented at the 7th International Conference on Health Policy Statistics, Philadelphia, PA, Jan. 17-18, 2008: Oral Presentation: http://www.jpscanlan.com/images/2008_ICHPS_Oral.pdf; PowerPoint Presentation: http://www.jpscanlan.com/images/2008_ICHPS.ppt
11. Measurement Problems in the National Healthcare Disparities Report, presented at American Public Health Association 135th Annual Meeting & Exposition, Washington, DC, Nov. 3-7, 2007: PowerPoint Presentation: http://www.jpscanlan.com/images/APHA_2007_Presentation.ppt; Oral Presentation: http://www.jpscanlan.com/images/ORAL_ANNOTATED.pdf; Addendum (March 11, 2008): http://www.jpscanlan.com/images/Addendum.pdf
12. Scanlan JP. Study illustrates ways in which the direction of a change in disparity turns on the measure chosen. Pediatrics Mar. 27, 2008 (responding to Morita JY, Ramirez E, Trick WE. Effect of school-entry vaccination requirements on racial and ethnic disparities in Hepatitis B immunization coverage among public high school students. Pediatrics 2008;121:e547-e552): http://pediatrics.aappublications.org/cgi/eletters/121/3/e547
13. Percentage Points sub-page of Vignettes page of jpscanlan.com: http://www.jpscanlan.com/vignettes/percentgepoints.html
Conflict of Interest:
None declared
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Distressing Internal Inconsistencies
Submit responseA primary source motivating the USPSTF to alter guidelines states that "conclusions about the optimal starting ages for screening depend more on the measure chosen for evaluating outcomes. If program benefits are measured in life-years, the measure most commonly used in cost- effectiveness analysis, then our results suggest that initiating screening at age 40 years saves more life-years... Starting annual screening at age 40 years (vs. 50 years) and continuing annually to age 69 years yields a median of 33 (range, 11 to 58) life-years gained per 1000 women screened. If the goal of a screening program is to efficiently maximize the number of life-years gained, then the preferred strategy would be to screen biennially starting at age 40 years (1)."
The USPSTF proceeds to ignore these comments to state "given that the age groups (40 to 49 years and 50 to 59 years) are adjacent, the Task Force elected to emphasize the mortality outcomes from the modeling studies." However, the USPSTF fails to describe how "adjacency" of the two age groups leads one to conclude that mortality outcomes is a better measure than life years gained. Further, the USPSTF does not counter the claim by their reference source that life years gained is "the measure most commonly used in cost-effective analysis."
Nelson's review, upon which the USPSTF relied to change their recommendations, states that "harms of mammography screening have been identified, but their magnitude and effect are difficult to measure. Mammography screening at any age is a tradeoff of a continuum of benefits and harms. The ages at which this tradeoff becomes acceptable to individuals and society are not clearly resolved by the available evidence (2)." However, the USPSTF chooses to emphasize the adverse consequences for most women and classifies harms for all age groups as "moderate."
The task force identifies false positives as the major harm in the younger age group. The task force indicates that it requires 565 more mammograms to save a life in the 40-49 year age group as compared to the 50-59 year group. Schell, et al, in evaluating the recall rate for 545,505 examinations in women aged 40-49, found that the rate is on the order of 9% which would lead to a "harm" of approximately 51 instances of additional views and/or ultrasound, 5 percutaneous biopsies under local anesthesia and the discovery of one cancer (at a rate of 3 cancers/1000 mammograms)(3). In order to conclude that the harm overshadows the life saved, the task force must find that the value of a human life is something less than the combined negative value of 616 imaging exams, 5 biopsies under local anesthesia, and the discovery of one new cancer.
In the newly passed Senate health reform bill, the USPSTF has been given a prominent role in determining what kind of care will and will not be allowed in a health care system. Under the new administration, this first effort by the USPSTF does not inspire confidence.
References
1. Mandelblatt JS, Cronin KA, Bailey S, Berry DA, de Koning HJ, Draisma G, et al. Effects of mammography screening under different screening schedules: model estimates of potential benefits and harms. Ann Intern Med. 2009;151:738-47.
2. Nelson HD, Tyne K, Naik A, Bougatsos C, Chan BK, Humphrey L. Screening for breast cancer: an update for the U.S. Preventive Services Task Force. Ann Intern Med. 2009;151:727-37.
3. M. J. Schell, B. C. Yankaskas, R. Ballard-Barbash, B. F. Qaqish, W. E. Barlow, R. D. Rosenberg, and R. Smith-Bindman Evidence-based Target Recall Rates for Screening Mammography Radiology, June 1, 2007; 243(3): 681 - 689.
Conflict of Interest:
None declared
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Hypomagnesemia by PPI's
Submit responseIt is quite an interesting finding reported by the authors and I applaud them for the same. It is a matter of serious concern considering that Proton pump Inhibitors are being increasingly prescribed by practitioners all over the world, even for non specific epigastric pain and for placebo effect in some cases. Considering the wide use of PPIs and seriousness of the symptoms caused by hypomagnesemia, the clinicians should develop high index of suspicion in cases with similar presentation. Though it is quite preliminary to generalize the hypomagnesemia side effect to other PPIs, developing high index of suspicion can help report similar findings especially considering the fact that magnesium measurements are being rarely done in the routine clinics. It will greatly enhance our understanding of the risk profile of the PPIs.
Conflict of Interest:
None declared
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US Preventive Services Task Force Recommendations on Screening for Breast Cancer
Submit responseAlthough the Task Force breast cancer screening recommendations are meant to provide guidance to clinicians and their patients, these and many other Task Force recommendations are also released in a public health arena and because they address entire or large segments of a population may have unintended or unforeseen public health impacts. Unfortunately, the current research and communications methodologies of the Task Force seem not to take this into account.
For example, the recommendation against clinicians teaching Breast Self Examination (BSE) I assume was related to a particular form of BSE. This appears to be based on several assumptions that fail to take into account the possible impact of this recommendation. First, it assumes that most such education occurs through interactions with clinicians. While the recommendation is only to clinicians, the Task Force fails to explain how this might or might not apply to other settings or persons,for example, health educators, public health departments. Nor does the lack of specificity regarding this recommendation account for the possibility that women be taught how to be more self aware of and how to conduct self examinations of their breasts for other reasons.
In addition, the language utilized in the recommendations indicates that the only concern is for clinicians and their patients. However, the recommendations are also widely disseminated in the media to populations of women who do not have health care coverage or clinicians they interact with on a regular basis - or if they do, only in emergency situations. One could easily hypothesize that the recommendations as perceived by these populations could have the unintended effect of not only decreasing use of breast cancer detection services (including public health services) but also conveying the impression that these are not important issues for those without regular health care. Furthermore, there is little consideration about what the impact on other health behaviors may be at a time when the entire health community is trying to get people to be more aware of and take a more active role in their health and health behaviors,and to shift towards prevention and early intervention before tertiary interventions may be required. While the Task Force properly tries to address one clinical issue at a time, it operates in an arena in which clinical and public health concerns and impacts naturally intermingle, where individuals apply what they have learned about one health behavior to another. As much as it may assume otherwise, the recommendations go not only to clinicians who have patients but to many who might be patients but in reality have little regular interaction with clinicians, and to non-clinicians who regularly address the same or similar health concerns with the patients of others.
It may be an overstatement that the Task Force exemplifies the unfortunate, and I think harmful, gap between our health care/clinical and public health systems. However, the Task Force format needs to be revised so that research and data from the public health arena be factored in and that there be recognition that the recommendations also have public health connotations which must also be factored in when making and releasing clincal recommendations. Richard Yoast, PhD
Conflict of Interest:
None declared
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Elimination of mammographic screening and breast self examination in women 40-50
Submit responseThe USPSTF recommendation that women in the age group 40-50 not have screening mammograms comes from poor judgment about breast cancer data and clinical understanding of breast cancer. Coupling this recommendation to the recommendation that women in this age group not examine themselves clearly indicates that the panel members have limited understanding of breast cancer detection. To be sure there is no good evidence that breast self-examination lowers the risk breast cancer death. However, by limiting themselves to the impact of self-examination on mortality, they failed to address a second question raised by their recommendation that these women not have mammographic screening. Who is it that most often diagnoses breast cancer in the age group of 40-50 years? In unscreened women it is overwhelmingly the women themselves. If one follows the USPSTF recommendations that women in this age should not be screened and should not perform self-examination, how are breast cancers to be diagnosed? Certainly this will not come from annual clinical breast examination.
Conflict of Interest:
None declared
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The USPSTF Recommendations should consider quality of life for breast cancer patients
Submit responseThe US Preventive Services Task Force (USPSTF) acknowledges that mammography screening, beginning at the age of 40, is not indicated for lower risk patients. Their guidelines, however, ignore the fact that breast cancer screening nowadays has two aims, from our point of view as breast surgeons. The first, of course, is regarding breast cancer deaths, which was discussed and can be easily calculated. But, the second one is related to the benefits of earlier diagnosis to breast surgery. We can preserve the breast and the axilla in most of patients with their breast cancer diagnosed in screening programs. Our current index of breast conservation surgery in a well selected population of brazilian patients in Curitiba (south of Brazil) who have access to screening today, is over 60%. Most of them (about 80%) had no axillary dissection, since the sentinel node was negative. These facts are directly related to quality of life in this group of patients. So there is a strong relation between screening and more conservative surgeries. I think that we can change our current recommendations in the future only if we consider the benefits to breast cancer patients in both aims. Mortality cannot be the only tool to be considered in the future guidelines. To save lifes is important, but to preserve quality of life is our current aim too in times of sentinel node and oncoplastic surgery.
Conflict of Interest:
None declared