作者：Roxanne Nelson
出處：WebMD醫學新聞
August 26, 2008 — 數十年來，我們鼓勵婦女每月進行乳房自我檢查（BSE），但是越來越多組織不建議常規自我檢查。研究評估BSE的好處發現結果相當混亂，直至上個月，媒體慌張地報導Cochrane的分析結果，發現BSE不但沒有改善乳癌存活率，事實上還可能是有害的。
然而，美國研究團隊的成員Mark Kane Goldstein博士與H.S. Pennypacker博士確立熟練的乳房檢查標準，這受到國家癌症機構（NCI）的支持，他們詳細指出媒體報導的錯誤，其中包含一些誤差以及忽略的重要資訊。
資深科學家、MammaCare委員會總裁Goldstein博士表示，這些新聞似乎已經對乳房檢查下了結語，且認為執行乳房自我檢查是無效，甚至是有害的；但那並不是事實。
MammaCare至今已經30年了，這是NCI支持的研究計劃，發展的目標在於教導有效的乳房自我檢查方法；目前，MammaCare負責醫療人員的乳房自我檢查教學，並授予證書。
Goldstein與Pennypacker博士解釋，媒體的報導未提及BSE的有效性，或是大型研究中BSE可偵測到乳癌的比例，這是關乎存活率的；媒體只報導構成Cochrane分析的兩項研究，而忽略矛盾的證據。
在與Medscape腫瘤學的訪談中，Goldstein博士解釋道，死亡率是Cochrane研究唯一的試驗終點，這很難被證實；他表示，一個單一的步驟就決定否影響壽命是很困難的，因此很難下結論說，乳房自我檢查會影響存活率。在這些研究當中有太多變項，很難獨立出一個去解釋像是死亡率這樣的結果。
【「更新」後更混亂】
Goldstein與Pennypacker博士指出，在報導中有些明顯的瑕疵，這些數據雖然被當作是新聞，但Cochrane綜論事實上已有5年之久；有些媒體把這些數據當成是新消息，原始的文章發表在2003年，且報導成最初結果的更新版。
Cochrane綜論發表於2003年4月22日（Cochrane Database Syst Rev. 2003; 2:CD003373），其分析兩項來自俄羅斯與中國上海的大型研究。這兩項研究都以乳房自我檢測、與未進行乳房自我檢測做比較，結果作者的結論是，透過BSE篩檢並沒有好處，相對的，他們發現確認出更多良性病灶，以及進行切片的數目增加的研究數據。
2003年Cochrane綜論的作者們最近重新進行分析，並搜尋Cochrane乳癌團隊專家註冊試驗、Cochrane圖書館，以及於2007年10月時搜尋PubMed來評估這個課題的新文獻。
來自丹麥哥本哈根Rigshospitalet的Nordic Cochrane中心，Jan Peter Koster醫師向Medscape腫瘤學表示，這項回顧性文獻已經更新，代表這項更新後的文獻中搜尋新的證據，因為這次的搜尋並未找到新的證據，更新後的結論仍然是一樣的。
當原始的Cochrane回顧性文章與更新後的文獻發表時，Medscape都有報導這些消息。
【新聞的遺漏與可用性】
美國癌症醫學會（ACS）醫療與科學交流主任David Sampson相信隨之而來的媒體焦點，顯然會從健康相關的消息開始，他表示，一旦我發現這並不是新的資訊或是變化，以及報導錯用ACS指引，我會提醒他們，不幸的，他們並沒有撤回新聞稿，因此每位讀者都認為這是個新聞。
跟這篇報導有關的另一個問題是，Goldstein與Pennypacker博士聲稱，這個新聞是偏頗的，僅將焦點放在Cochrane分析結果。整體而言，媒體遺漏了來自美國與歐洲的研究，這些研究結果發現，BSE與偵測到乳癌及這些患者的存活率有關；這包括了今年發表的研究結果（Singapore Med J. 2008; 49: 228-232），這項研究確認了BSE的價值，如果對BSE的支持在媒體報導中有所著墨，都傾向成描寫為流傳的說法，而非臨床研究的證據。
Kosters博士解釋，在Cochrane分析中，僅有符合事先定義的收納條件才會被納入，這些條件一般而言被臨床科學領域所接受。
Goldstein博士指出，雖然媒體報導重複自我檢測乳房腫塊可能增加良性組織非必需切片的數目，但他們並沒有提到所有的乳房篩檢方法都有這樣的問題。
他表示，所有的篩檢方法都可能導致偽陽性；大約11%的乳房攝影結果是偽陽性的，每年大約有3百萬人是這樣的結果。
Goldstein博士解釋，這項文獻本身的一個限制是，這並沒有提供這些結論如何應用到其他國家族群的資訊，例如美國；上海研究的試驗終點是死亡率，而不是自我偵測到乳癌的機率或是發病率，且相較於美國，中國在醫療科技與治療選擇上比較沒有那麼先進或積極，乳癌偵測的結果是受到干擾的，且不能正確地與美國、或是西方女性相比較，或是將這些結果應用到女性身上。
Kosters博士不同意這樣的看法，並宣稱這只是個假設；他表示，就他所知，並沒有臨床研究證據支持這樣的說法。
【混雜的訊息】
雖然目前並未達到確切的共識，許多主要的組織、以及遊說團體已經停止建議常規性的BSE，因為缺乏強烈證據顯示這是有益的。
ACS在2003年停止建議BSE，主要是根據Sampson先生原始的Cochrane分析結果；加拿大癌症學會也已經停止建議常規性的BSE。其他健康組織支持這項改變，包括加拿大預防健康照護任務小組、世界衛生組織、美國預防服務小組、與英國國家健康服務。
即使他們仍然在網站上將BSE作為自我篩檢的工具，但Cure網站的Susan G. Komen不再建議每月進行BSE；在一項聲明中，其科學顧問Eric P. Winer醫師強調，女性應該清楚她們的乳房外觀與觸感，他表示，這對於女性注意她們的乳房正常外觀與觸感來說是非常重要的，如果有任何變化的話，都應該告知她們的醫師。
NCI採取較為中性的作法，NCI的公關主任Aleea Farrakh向Medscape腫瘤學表示，我們有證據等級，但是我們對於BSE並沒有嚴格的建議。
美國婦產科醫學會在最近的乳房篩檢指引中保留了BSE；該指引提到，並沒有確切的數據反對乳房自我檢查，這項檢查仍是具有偵測可觸摸到乳癌的潛力，且可以被建議。
許多遊說團體也繼續建議BSE，包括舊金山乳癌行動，這個團體宣稱經由受過訓練的健康照護者進行的年度臨床乳房檢查，與乳房自我檢查，在乳房篩檢上都是最基本的。「我們的身體是我們自己的（Our Bodies Ourselves）」，也被稱為波士頓女性健康書籍集團，這是一個非營利公共女性教育與擁護組織，他們指出BSE很少作為唯一的篩檢工具，這一般要結合臨床乳房檢驗乳房攝影，以及是女性唯一一項可以用她們的雙手控制的篩檢方法。
Goldstein博士與Pennypacker表示，大部分的乳癌是可以觸摸的，且一般都是由女性自身發現；當佛羅里達州與MammaCare的生物醫學研究團隊第一次研究最佳的觸摸篩檢方法，他們發現，以觸覺準確乳房模型，以及小的模擬病灶，這樣的技巧訓練讓女性與健康照護者練習確實地找出3 mm大小的乳房病灶，這比意外發現的病灶平均大小小了10倍。
他們寫道，已經發表的證據舉證了大部分的乳癌是可以觸摸的，也是可以自我偵測的，且某些乳癌是乳房攝影看不到的，有效的乳房自我篩檢已經受到確效，這樣的技術是可以學習的，學習並練習乳房檢驗，女性可以獲得保護自己健康與生命的好處。
Media Coverage About Breast Self-Exam Misleading, Say Experts
By Roxanne Nelson
Medscape Medical News
August 26, 2008 — For decades women have been urged to perform a monthly breast self-examination (BSE), but recently, an increasing number of organizations have backed away from recommending routine self-exams. Studies evaluating the benefit of BSE have shown decidedly mixed results and, last month, a flurry of media stories reported on a Cochrane analysis that showed that BSE does not improve breast cancer survival and might, in fact, cause harm.
However, Mark Kane Goldstein, PhD, and H.S. Pennypacker, PhD, both members of the American research team that identified and validated the standards for proficient breast examination, with the support of the National Cancer Institute (NCI), pointed out in a detailed response that the media coverage was misleading, contained a number of errors, and omitted critical information.
"The news stories seem to suggest that this is the final word on breast self-exam, and that the practice is ineffective or even harmful," said Dr. Goldstein, senior scientist and chairman of the board at MammaCare, in Gainesville, Florida. "And that's not the case at all."
MammaCare began more than 30 years ago as a research project supported by the NCI, with the goal of developing a program to teach efficient manual breast examination. Currently, MammaCare teaches and certifies healthcare professionals to perform clinical breast examination.
Drs. Goldstein and Pennypacker explained that the media stories made no mention of studies that have demonstrated the efficacy of BSE, or that major published studies have documented the fact that BSE has accounted for a substantial proportion of breast cancer detections, and that it is associated with survival. Reports in the popular media also largely ignored the contradictory evidence that was published within the 2 studies that comprised the Cochrane analysis.
In an interview with Medscape Oncology, Dr. Goldstein explained that mortality was the only end point in the Cochrane studies, and that can be difficult to validate. "It is hard to determine whether a single procedure can affect longevity, so it is difficult to come to clear conclusions about the effect of breast self-exams on survival," he said. "There are too many variables in these types of studies to isolate just 1 for an outcome such as mortality."
Confusion Over "Update"
One glaring flaw in the media stories, Drs. Goldstein and Pennypacker pointed out, was that even though the data were presented as news, the Cochrane review is actually 5 years old. Some media outlets presented the data as brand new, whereas others made reference to the fact that the original article appeared in 2003 and issued the story as an update of the initial results.
The Cochrane review, published on April 22, 2003, analyzed data from 2 large population-based studies conducted in Russia and Shanghai, China (Cochrane Database Syst Rev. 2003; 2:CD003373). Both studies compared breast self-examination with no intervention, and the authors of the Cochrane analysis concluded that the data did not suggest a beneficial effect of screening by BSE. Instead, they found that the data suggested increased harm in terms of greater numbers of benign lesions identified and an increased number of biopsies performed.
The authors of the 2003 Cochrane analysis recently revisited this analysis, and searched the Cochrane Breast Cancer Group Specialised Register, The Cochrane Library, and PubMed in October 2007 to evaluate new literature on the subject.
"The review has been updated, meaning that a new search for evidence has been conducted as stated in the updated review," Jan Peter Kosters, MD, from the Nordic Cochrane Centre at Rigshospitalet, in Copenhagen, Denmark, told Medscape Oncology. "Since this search did not find new evidence, the conclusions in the updated review remain the same."
The original Cochrane review and the updated review were both reported by Medscape when they were published.
Omissions and Applicability
David Sampson, director of medical and scientific communications at the American Cancer Society (ACS), believes that the ensuing widespread media coverage got its start from a press release that appeared on a health-related newswire. "I alerted them as soon as I found out that this was not new information or a change, and that the report inaccurately quoted ACS guidelines," he said. Unfortunately, "they did not rescind the press release, so everyone covered this as news."
Another problem with the reporting, contend Drs. Goldstein and Pennypacker, is that news articles tended to be 1 sided, focusing only on the results of the Cochrane analysis. Media outlets generally omitted any mention of results from major American and European studies that found BSE to be associated with a substantial proportion of detected breast cancers and survival. This includes findings from a study published this year (Singapore Med J. 2008;49:228-232), which confirmed the value of BSE. If support for BSE was mentioned in media reports, it tended to be anecdotal accounts, not evidence from clinical trials.
Dr. Kosters explained that, in the Cochrane analysis, "only studies that met the predefined inclusion criteria were included. These criteria are generally accepted in the clinical–scientific community."
Dr. Goldstein pointed out that although media reports repeated the finding that self-detected breast lumps might lead to an increase in unnecessary biopsies of benign tissue, they failed to mention that this is true of every method of breast cancer screening.
"All screening methods lead to false positives," he said. "About 11% of mammograms are false positive. That's about 3?million a year."
A limitation of the review itself, explained Dr. Goldstein, is that it doesn't provide information on how the conclusion might apply to populations in other countries, such as the United States. The end point in the Shanghai study was mortality rather than self-detected breast cancer or morbidity, and because medical technology and treatment options are less advanced or aggressive in China than in the United States, the outcomes of breast cancer detection are confounded and cannot be accurately compared with or transferred to American or Western women.
Dr. Kosters disagrees, and states that is just a hypothesis. "As far as I know, there is no evidence from clinical studies to support this statement," he said. "General screening of a healthy population needs to be tested in clinical trials of good quality."
Mixed Messages
Although a definitive consensus has yet to be reached, many of the major organizations and advocacy groups have stopped recommending routine BSE because of the lack of strong evidence showing a clear benefit.
The ACS stopped recommending BSE in 2003, based on the data from the original Cochrane analysis, according to Mr. Sampson. The Canadian Cancer Society also stopped recommending routine BSE. Other health organizations supporting this change include the Canadian Task Force on Preventive Health Care, the World Health Organization, the US Preventive Services Task Force, and the UK National Health Services.
Even though they still have a BSE instructional screening tool on their website, the Susan G. Komen for the Cure website no longer recommends a monthly BSE. In a statement, Eric P. Winer, MD, their chief scientific advisor, stressed that women should be familiar with how their breasts look and feel. “It is important for women to be aware of the normal look and feel of their breasts and report any changes to their doctors,” he said.
The NCI takes a more neutral approach. "We have levels of evidence," NCI press officer Aleea Farrakh told Medscape Oncology, "but we do not have any strict recommendations regarding BSE."
The American College of Obstetricians and Gynecologists has kept BSE in its most recent breast cancer screening guidelines. "Despite a lack of definitive data for or against breast self-examination, breast self-examination has the potential to detect palpable breast cancer and can be recommended," the guidelines state.
Several advocacy groups also continue to recommend BSE, including San Francisco–based Breast Cancer Action, which states that annual clinical breast exams by trained health professionals and breast self-exams are essential aspects of breast cancer screening. Our Bodies Ourselves, also known as the Boston Women’s Health Book Collective, a nonprofit public-interest women’s health education and advocacy organization, points out that BSE is rarely used as a sole screening method, is generally combined with clinical breast exam and mammography, and is the only detection method that women have control over with their own 2 hands.
Most breast cancers are palpable and are usually discovered by the women themselves, Drs. Goldstein and Pennypacker note. When the biomedical research team at the University of Florida and MammaCare were first investigating optimal palpation procedures, they found that skill training using tactually accurate breast models with small simulated lesions enabled women and healthcare practitioners to reliably detect 3?mm breast lesions, which is 10 times smaller than the average lesion found by accident.
"Published evidence documents that a large proportion of breast cancers are palpable and self-detected, that some breast cancers are mammographically invisible, that the components of effective breast self-examination are now known and validated, that the skill can be learned, and that women who learn and practice proficient breast examination possess an advantage in protecting their health and their life," they write.
[ 本帖最後由 goodcat1111 於 2008-9-5 20:11 編輯 ] |
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