本帖最後由 goodcat1111 於 2009-4-5 08:18 編輯
作者：Roxanne Nelson
出處：WebMD醫學新聞
March 9, 2009 — 根據3月9日癌症期刊線上版的一篇報告，帶有BRCA突變的婦女比較可能將預防性乳房切除視為減少乳癌風險的最佳方法，也可減少她們對發生此病的焦慮；研究發現，儘管有比較不激烈的選項，但多數病患相信預防性乳房切除是最佳選擇。
主要作者、德州大學安德森癌症中心的Jennifer K. Litton醫師表示，決定進行預防性乳房切除是相當個人化的，包括了許多因素，例如性慾、體型與擔憂癌症；有時候，當婦女有BRCA1或BRCA2突變時，可以進行篩檢，以期及早發現一些問題，而可以進行一些預防策略。
這項研究聚焦在評估有關高風險婦女的篩檢選項以及手術選項。Litton醫師向Medscape Oncology表示，並非此篩檢難以進行，而是預防性乳房切除是降低風險與降低發生乳癌數量的最佳方法。通常是有明顯家族史的婦女、以及個人與家人有切身經驗者會做此決定。
最近的一篇後設分析估計，乳癌的終身風險在BRCA1突變者是47%至66%，BRCA2突變者是40%至57% (J Clin Oncol. 2006;24:863-871)。作者指出，其他研究顯示的估計更高。已知帶有有害突變婦女的風險管理，包括經常篩檢以及預防性手術，但是病患通常難以決定何者對她是最好的。
Litton醫師等人調查於2005年7月前在其機構內接受BRCA1/2基因檢測的540名婦女，對檢測發現有害突變為陽性者的反應與檢測陰性者的反應進行比較；分析婦女選擇同意或不同意的選項，作者們使用雙向費雪精確檢定來比較這些反應。
回覆調查的312名婦女中，217 (70%)人報告有乳癌，86 (28%)人的BRCA1或BRCA2基因有害突變檢測為陽性。
【子宮切除被視為最佳策略】
BRCA突變檢測陽性的婦女中，70%同意預防性乳房切除是降低風險的最佳策略；當被問到進行預防性乳房切除是否為唯一降低發生乳癌的方法時，BRCA-陽性者有 64.7%、BRCA-陰性者有34.4%表示同意。
此外，也詢問這些參與調查者，是否認為以預防性乳房切除術來預防乳癌太過激烈。BRCA-陽性者有36.1%、BRCA-陰性者有40.5%表示同意。
BRCA-陽性者有28%表示未接受預防性乳房切除術的主要原因是對手術的恐懼，BRCA-陰性者則有21.9%；當被問到不接受手術的主要原因是否是影響外觀時，BRCA-陽性者有33.8%、BRCA-陰性者有27.7% 表示同意。
BRCA-陽性婦女中，23.9%同意在篩檢和預防性乳房切除上難以抉擇，BRCA-陰性者有12.5%。調查結果也發現，BRCA突變檢測陽性的婦女，沒有人因為乳房攝影過程之不適而認為有困難，BRCA-陰性者則有5.4%。
Litton醫師解釋，他們已經蒐集了有關降低卵巢癌風險的資料，她表示，這將另外單獨發表，但有許多決定進行預防性乳房切除的婦女，已經或者計畫在完成生育計畫之後進行卵巢切除。
當醫師和病患討論治療選項時，Litton醫師建議，提出檢查和預防的手術應只是討論的一部份，還要顧慮到個人、其考量、以及預防性手術的生活經驗諮商等。
Nellie B. Connally乳癌研究基金以及NIH 訓練資金支持本研究。
Cancer. 印行前，線上發表於2009年3月9日。
Women With BRCA Mutation Most Likely Opt for Prophylactic Mastectomy
By Roxanne Nelson
Medscape Medical News
March 9, 2009 — Women who carry the BRCA mutation are more likely to view prophylactic mastectomy as the best way to reduce their risk for breast cancer and their anxiety about developing the disease, according to a report published online March 9 in Cancer. The study found that despite the availability of less drastic options, most patients in this population believed that a prophylactic mastectomy was the best choice.
"The decision to undergo prophylactic mastectomy is very personal," said lead author Jennifer K. Litton, MD, from the University of Texas MD Anderson Cancer Center, in Houston. "There are a lot of factors involved, including sexuality, body image, and worry of cancer. Sometimes when women have a BRCA1 or 2 mutation, they may do screening in the hope of finding something early, but often that may be a bridge to preventative strategies."
The decision to undergo prophylactic mastectomy is very personal.
The focus of this study was to evaluate opinions regarding screening and surgical options for high-risk women. "It is not that the screening is too hard or difficult, but that prophylactic mastectomy was the best way to reduce risk and the best way to reduce the amount of worry over developing a breast cancer," Dr. Litton told Medscape Oncology. "Women with strong family histories often have significant personal and family experience with cancer that is integral to this decision."
A recent meta-analysis estimated that the lifetime risk for breast cancer was 47% to 66% in carriers of the BRCA1 mutation and 40% to 57% in carriers of the BRCA2 mutation (J Clin Oncol. 2006;24:863-871). Other studies have shown even higher estimates, the authors note. Risk management for women with a known deleterious mutation includes frequent screening and prophylactic surgeries, but patients often have difficulty deciding which option is best for them.
Dr. Litton and colleagues surveyed 540 women at their institution who had undergone BRCA1/2 genetic testing before July 2005. The responses of those who tested positive for a deleterious mutation were compared with responses of those who tested negative; for women who expressed an opinion (agree vs disagree), the authors used a 2-sided Fisher's exact test to compare responses.
Of the 312 women who responded to the survey, 217 (70%) reported having breast cancer, and 86 (28%) tested positive for a deleterious mutation in either the BRCA1 or BRCA2 gene.
Mastectomy Believed Best Strategy
Of the women who tested positive for a BRCA mutation, 70% agreed that prophylactic mastectomy was the most effective strategy for reducing risk. When asked if undergoing a prophylactic mastectomy was the only way to reduce the worry of developing breast cancer, 64.7% of BRCA-positive and 34.4% of BRCA-negative women agreed that it was.
Survey respondents were also asked if they felt that prophylactic mastectomy was too drastic a measure to prevent breast cancer. A total of 36.1% of the BRCA-positive and 40.5% of the BRCA-negative women agreed. Almost 28% of BRCA-positive women agreed that the main reason for not undergoing prophylactic mastectomy was the fear of surgery, compared with 21.9% of BRCA-negative women. When asked if the main reason for not undergoing surgery was that it is too disfiguring, 33.8% of BRCA-positive and 27.7% of BRCA-negative women agreed.
Of the BRCA-positive women, 23.9% agreed that it was difficult to choose between screening and undergoing a prophylactic mastectomy, as did 12.5% of BRCA-negative women. The survey results also revealed that none of the women who tested positive for a BRCA mutation felt that mammograms were difficult because the procedure was too uncomfortable, compared with 5.4% of BRCA-negative women.
Dr. Litton explained that they did collect information regarding ovarian cancer risk reduction. "That will be part of a separate publication," she said, "but many women who decide to undergo prophylactic mastectomy have already or plan to undergo oophorectomy after the completion of childbearing."
When clinicians discuss management options with their patients, Dr. Litton suggests that "presenting screening and preventative surgeries should all be a part of the discussion, as well as the individual, their concerns, and their life experience when counseling for prophylactic surgeries."
The study was supported by the Nellie B. Connally Breast Cancer Research Fund and an NIH Training Grant.
Cancer. Published online before print March 9, 2009. |
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