马里兰大学的Randi J. Cohen博士在美国放射肿瘤学会(ASTRO)年会上报告，对于早期乳腺癌患者，年龄大本身并不应当被视为乳房肿瘤切除术后放疗的不利因素。在老年乳腺癌患者中，接受术后放疗者的5年、10年总生存率和癌症特异性生存率均高于仅接受乳房肿瘤切除术者。

Randi J. Cohen博士

　　研究者对29949名年龄70~84岁、生存至少1年的临床Ⅰ期、雌激素受体阳性乳腺癌患者的数据进行了分析。大约3/4的受试者在乳房肿瘤切除术后接受了放疗。

　　结果显示，接受乳房肿瘤切除术+放疗者的5年总生存率为88.6%，高于未放疗组的73.1%(P＜0.0001)。两组患者的10年总生存率分别为65.0%和41.7%。两组患者的5年原因特异性生存率分别为98.3%和97.4%，10年时分别为95.5%和93.3%(均P＜0.0001)。乳房肿瘤切除术+放疗组患者的中位生存期也长于单纯乳房肿瘤切除术组，分别为13.1年和11.1年。

　　放疗是独立预测因素

　　校正年龄、肿瘤大小、种族、导管组织学、淋巴结和婚姻状况的多变量分析也显示，不接受放疗者的结局明显更差，总生存率和原因特异性生存率的危险比(HR)分别为1.56和1.41。

　　上述结果与早期乳腺癌试验者协作组(EBCTCG)的一项Meta分析结果很相似。这项Meta分析显示，加用放疗可使10年生存率的绝对值增加3%。而根据本项研究，加用放疗可使10年生存率的绝对值增加2.2%。

　　Cohen博士称，2004年癌症与白血病B组(CALGB)的一项试验促使她开展了本项研究。这项2004年试验招募了630例≥70岁的女性早期乳腺癌患者，评价了在乳房肿瘤切除术+阿莫西芬的基础上加用放疗是否能改善乳腺癌特异性生存率。经过中位时间10.5年的随访，研究者发现加用放疗者的相同乳腺癌复发率降低了6%，但总生存率和无病生存率均无差异。

　　Cohen博士认为，EBCTCG研究和本项研究中显示的放疗获益，可能与局部区域控制水平提高有关。本项研究中放疗对总生存率的益处可能源于选择了相对更健康、预期寿命更长的患者接受放疗。但她承认，缺乏复发率和激素治疗相关数据是本项研究的一大局限性。

　　获益程度仍有疑问

　　耶鲁大学的Meema Moran博士评论指出：“原因特异性生存率方面的获益程度不太可能仅仅取决于放疗。”她注意到，在EBCTCG研究中，加用放疗仅能使这一相对低危的人群在15年时获得3%的生存益处，这一益处可能部分来源于治疗选择偏倚。

　　她还指出，由于本项研究未收集局部复发数据，研究者将无乳房切除术生存率作为复发的替代指标，然而乳房切除率可能因同侧复发的治疗方式不同(乳房切除术或再次保乳手术)而异。

　　Cohen博士未披露本项研究的资金来源。她自称无相关利益冲突。Moran博士报告称为基因组健康咨询委员会提供了服务。

　　相关链接: Internal Medicine News Digital Network

       Older Women Lived Longer With Radiotherapy After Lumpectomy  

　　BOSTON – A review of data on nearly 30,000 women suggests older age by itself should not be a barrier to radiotherapy after lumpectomy for early-stage breast cancer.

　　Older patients treated with both modalities had higher rates of overall and breast cancer–specific survival at 5 and 10 years compared with women who underwent lumpectomy alone, investigators reported at the annual meeting of the American Society for Radiation Oncology.

Courtesy American Society for Radiation Oncology

"The improvement in cause-specific survival with the addition or radiation suggests that in healthy, elderly women, adjuvant radiation should be strongly considered as part of their breast cancer treatment," said Dr. Randi J. Cohen, a radiation oncologist at the University of Maryland in Baltimore.

　　The review examined Surveillance, Epidemiology, and End Results (SEER) database records on 29,949 women, who were aged 70-84 years at diagnosis with clinical stage I, estrogen receptor–positive breast cancer and survived at least 1 year. About three-fourths underwent radiation after lumpectomy.

　　Women treated with lumpectomy and radiation had an overall survival rate of 88.6% at 5 years vs. 73.1% among those with no radiation (P less than .0001), Dr. Cohen reported. Overall survival rates at 10 years were 65.0% and 41.7%, respectively.

　　Cause-specific survival rates at 5 years were 98.3% for patients in the radiation plus surgery group and 97.4% for those with no radiation. At 10 years, the respective rates were 95.5% and 93.3% (P less than .0001 for both comparisons).

　　The median length of survival also was greater with the addition of radiotherapy – 13.1 years vs. 11.1 years with lumpectomy alone.

　　Radiation Was Independent Predictor

　　In multivariate analysis that controlled for age, tumor size, race, ductal histology, lymph nodes and marital status, hazard ratios also showed significantly worse outcomes without radiation – 1.56 in the overall survival analysis and 1.41 in the cause-specific survival analysis.

　　The results are similar to those in a meta-analysis from the Early Breast Cancer Trialists’ Collaborative Group (EBCTCG), said Dr. Cohen. That study showed an absolute benefit for adding radiation of 3% at 10 years, compared with 2.2% at 10 years in the current study.

　　Dr. Cohen said the review was prompted by questions raised in a 2004 study from the Cancer and Leukemia Group B (CALGB). In that trial, investigators looked at whether adding radiation to lumpectomy plus tamoxifen would have an effect on overall or breast cancer–specific survival in 630 women 70 years and older with early-stage disease. They found that at a median follow-up of 10.5 years, there was an absolute reduction of 6% in same-breast tumor recurrence with radiation, but no difference overall of disease-free survival.

　　In the much larger EBTCG study and the current study, however, the disease-specific survival advantages with the addition of radiation were likely related to greater locoregional control. Dr. Cohen said that the overall survival advantage in her study was probably due to selection of healthier patients with longer predicted life expectancy for radiotherapy.

　　She noted, however, that the study was limited by a lack of data on recurrence rates or hormonal therapy.

　　Strength of Benefit Questioned

　　"It’s highly unlikely that the magnitude of the benefits of cause-specific survival can be attributed to just radiation alone," said Dr. Meema Moran, the invited discussant. She noted that in EBCTCG study, there was only about a 3% benefit at 15 years in a seemingly low-risk population with shorter follow-up. The favorable survival in the meta-analysis may therefore be partly attributable to treatment selections bias, said Dr. Moran, a radiation oncologist at Yale University in New Haven, Conn.