移除轉移乳癌的原發腫瘤可以延長存活
作者：Roxanne Nelson
出處：WebMD醫學新聞
September 21, 2009 (德國柏林) — 手術移除轉移乳癌病患的原發腫瘤，可以大幅改善存活，但這不屬於現有的標準實務。根據發表於第15屆歐洲癌症組織研討會以及第34屆歐洲腫瘤醫學會(ESMO)聯合研討會的一篇研究資料，移除腫瘤可以有加倍的整體存活。
研究作者、荷蘭Jeroen Bosch醫院的外科住院醫師Jetske Ruiterkamp表示，移除腫瘤可以降低40%的死亡率。
Ruiterkamp醫師在記者會中解釋，接受手術之病患的存活中位數顯著比那些沒有接受手術者長(31個月vs 14個月)；移除腫瘤之病患的5年存活率為24.5%，未接受手術者是13.1%。5年存活率的差異相當顯著(P< .0001)。
在荷蘭，有九分之一的婦女診斷有乳癌，其中，3%至10%在診斷時有遠端轉移。Ruiterkamp醫師表示，一般而言，末期乳癌採取緩和治療，原發腫瘤只有在有症狀時才會移除。
不過，最近的資料顯示，移除原發腫瘤可以有正面結果且延長存活。在一篇回溯研究中，Ruiterkamp醫師等人在控制年紀和相關共病症等可能干擾因素之後，分析了手術切除對病患存活的影響。
1993至2004年間，在荷蘭南部共有15,769名婦女診斷有乳癌。其中，728人在最初診斷時即有遠端轉移，相當於該國所有乳癌病患的5%。約有40%末期乳癌病患接受手術移除原發腫瘤。
研究者採取分類分析以比較手術和非手術治療病患，且根據年紀、T分類、共病症、轉移部位數量等分成小組。此外，進行多變項分析以評估手術的單獨影響。
多變項分析顯示，校正年紀、診斷期間、T分類、共病症、轉移部位數量、使用局放射線治療、使用全身性治療等因素之後，手術是整體存活的一個獨立預後因素。
目前，研究者回顧選定之病患的病歷，探討進行的手術類型等因素，瞭解手術邊界等資訊，以及是否進行淋巴結切除。她表示，此一資訊有助於找到這些結果的生物學解釋。
她指出，當我們進行病歷回顧時，或許可以發現進行手術的原因。
ESMO總裁Jose Baselga醫師指出，雖然這些結果是有趣的，手術移除原發腫瘤在這類病患並不常見。他在評論時向Medscape Oncology表示，這是該研究的偏見。
他表示，通常基於後述的兩個原因之一才會移除原發腫瘤。其一，腫瘤引起併發症，其二，病患要求移除。後者的案例中，婦女情況良好但是仍然想切除腫瘤。
他指出，原發腫瘤可能會繼續產生細胞進入循環，因此，手術是讓原發腫瘤自行封閉；不過，單就這些資料並不會改變目前的實務，需要進行隨機臨床試驗。
Ruiterkamp醫師表示同意。即使多變項分析顯示手術是整體存活的獨立因素。她結論表示，仍應進行隨機控制試驗，以確認手術真的有任何好處。
第15屆歐洲癌症組織研討會(ECCO 15)以及第34屆歐洲腫瘤醫學會(34th ESMO)聯合研討會：摘要5005。發表於2009年9月21日。
Removal of Primary Tumor in Metastatic Breast Cancer May Prolong Survival
By Roxanne Nelson
Medscape Medical News
September 21, 2009 (Berlin, Germany) — Surgical removal of the primary tumor in patients with metastatic breast cancer — which is not currently standard practice — could greatly improve survival. According to data from 1 study presented here at the 15th Congress of the European CanCer Organization and the 34th European Society for Medical Oncology (ESMO) Multidisciplinary Congress, tumor removal was associated with a doubling of overall survival.
"Removing the tumor was associated with a 40% reduction in mortality," said study author Jetske Ruiterkamp, MD, a surgical resident at the Jeroen Bosch Hospital in Den Bosch, the Netherlands.
The median survival of patients who underwent surgery was substantially longer than those who did not (31 months vs 14 months). "The 5-year survival rates were 24.5% for patients who had their tumor removed, compared with 13.1% for those who didn't," explained Dr. Ruiterkamp during a press briefing. This 5-year survival difference was highly significant (P?< .0001).
In the Netherlands, 1 of 9 women are diagnosed with breast cancer, and of this cohort, 3% to 10% have distant metastases at the time of their diagnosis. Generally, advanced-stage breast cancer is treated palliatively, and the primary tumor is removed only if it is symptomatic, Dr. Ruiterkamp said.
However, recent data suggest that removing the primary tumor could have a beneficial effect on outcome and extend survival. In a retrospective study, Dr. Ruiterkamp and colleagues analyzed the impact that surgical resection had on patient survival, after accounting for potential confounders such as age and associated comorbidities.
A total of 15,769 women were diagnosed with breast cancer in the south of the Netherlands between 1993 and 2004. Of this group, 728 patients had distant metastases at their initial diagnosis, representing 5% of all breast cancer patients in that region of the country. Approximately 40% of the patients with advanced-stage disease had undergone surgical removal of the primary tumor.
The researchers conducted stratified analyses to compare surgically and nonsurgically treated patients in subgroups that were defined by factors such as age, T-classification, comorbidity, and the number of metastatic sites. In addition, a multivariate analysis was performed to evaluate the independent contribution that surgery might have had.
The multivariate analysis showed surgery to be an independent prognostic factor for overall survival, after adjustment for age, period of diagnosis, T-classification, comorbidity, number of metastatic sites, use of locoregional radiotherapy, and use of systemic treatments.
Currently, the researchers are reviewing medical charts of selected patients and looking at factors such as the type of surgery that was performed, information about surgical margins, and whether lymph node dissection had taken place. This information will help find a biologic explanation for these results, she said.
"When we do the chart review, maybe we can also find out the reasons for having the surgery," she added.
Although these results are interesting, Jose Baselga, MD, president of ESMO, pointed out that surgical removal of the primary tumor is not commonly done in this patient population. "That is the bias of the study," he told Medscape Oncology when approached for independent comment.
The primary tumor is usually removed for 1 of 2 reasons, he said. "One is if the tumor is causing complications and the second is if the patient asks for it to be removed. In the latter case, the woman may be doing well and would like to remove the tumor."
It might be that the primary tumor continues to launch cells into circulation, so the surgery is a self-sealing of the primary tumor, he added. "However, these data alone are not going to lead to a change in current practice. Randomized clinical trials are needed."
Dr. Ruiterkamp agreed. Even multivariate analysis showed that surgery is an independent factor in overall survival. A randomized controlled trial should be performed to see if surgery really has any benefit, she concluded.
15th Congress of the European CanCer Organization (ECCO 15) and the 34th European Society for Medical Oncology (34th ESMO) Multidisciplinary Congress: Abstract 5005. Presented September 21, 2009.
