Finding Breast Cancer Early Saves Lives
In a landmark study, Dutch researchers have found that detecting breast cancer at an early stage saves lives, even in this era of targeted therapies, new chemotherapy options and more conservative surgery. The findings have been widely publicized in the press.
What is already known
It is known that survival is correlated with tumor size and number of positive lymph nodes, i.e. increasing size and number of nodes leads to decreased survival. However, only rare studies looking at more recent data (patients after 2004) exist.
Since 2004, chemotherapy regimens have improved, leading to increases in survival rates.
It is unknown how stage (tumor size and number of positive lymph nodes) at breast cancer detection, impacts survival in modern times.
What this study finds
The current study examined almost 174,000 Dutch women between 1999 and 2012. They found a 91% 5 year survival rate for the 1999-2005 cohort, whereas those from 2006-2012 had a 96% 5 year survival rate.
They found that both tumor size and nodal status still have a major influence on overall mortality. This is independent of age, tumor biology, more conservative surgery and newer chemotherapy regimens.
Thus, early stage at detection saves lives. Surgery is imperative, with more conservative approaches resulting in more favorable outcomes.
This study will give critics of mammogram guidelines a renewed argument in favor of yearly screening. Currently the US Preventive Services Task Force (USPSTF) recommends screening women aged 50-74 years every other year. The decision to start regular, biennial screening mammography before the age of 50 years should be a individualized, taking patient context into account, including the patient's values regarding specific benefits and harms in a shared decision making process with one’s physician. The USPSTF states there is insufficient evidence to offer screening mammograms to women 75 and older. From the study, it is clear that yearly screening does save lives.
The study also gives reassurance that conservative surgery is as good as mastectomy. The findings prove that consistent high quality care makes a difference. The 5 year breast cancer survival rate in the Netherlands is 96%, while that of small tumors is 100%. Currently the US 5 year breast cancer survival rate is 90%. Clearly, much can be learned from our Dutch colleagues.