5-Year Cancer Survival Rates Are Increasing

A quick look at the latest figures from SEER, the statistical database provided by the National Cancer Institute, shows that survival rates for most forms of cancer have increased dramatically over the past 30 years or so. Overall, 5 year cancer survival rates have increased from 48.9% in 1975 to 66.7% in 2003. The following graph shows 5-year survival rates for some of the most common forms of cancer.

Trends in cancer survival rates graph

Prostate cancer has shown the most impressive survival rate increase with 99.4% of prostate cancer patients surviving at least 5 years compared to just 66.4% in 1975. This increase has been brought about primarily through increased use of the prostate-specific antigen test leading to a greater percentage of prostate cancer cases being diagnosed early.

More than 90% of prostate cancers are diagnosed when the cancer is still localized. At this early stage, 5-year survival rates run at 99.95% compared to just 29% for advanced prostate cancer which has metastasized to distant locations.

Non-hodgkin lymphoma has also seen significant improvements in 5 year survival rates with an increase from 46% in 1975 to 70.2% in 2003. Improvements in survival for non-Hodgkin lymphoma have been the result of new treatments such as monoclonal antibody therapy. Rituximab is one such monoclonal antibody which targets B-cell non-Hodgkin lymphomas and can lead to significant increases in survival rate when used in conjunction with chemotherapy regimes.

Breast cancer and colorectal cancer have both benefited from increased levels of screening. Breast cancer survival rates have increased from 75.5% to 89.9% while colorectal cancer survival rates have increased from 48.7% to 65.6%. When breast cancer is still localized, 5-year survival rates are as high as 98.6% compared to 23.4% for advanced breast cancers. Breast cancer screening, typically in the form of mammograms, increases the likelihood of detecting breast cancer in its early stages. Studies have found substantial reductions in breast cancer mortality as a result of breast cancer screening. This study found a 31% reduction in mortality and a 25% reduction in the rate of advanced breast cancers as a result of a mass screening program in Sweden.

Colorectal screening is slightly more controversial because the most common screening method, the colonoscopy, carries a serious complication rate of around 5 per 1,000 colonoscopies. Despite this, the decreased risk of being diagnosed with advanced colorectal cancer is generally thought to outweigh the small risk of complications.

Other forms of cancer have shown little or no change in survival rates over the last few decades. These include lung cancer, mesothelioma, pancreatic cancer, and some of the more aggressive forms of brain cancer such as glioblastoma multiforme. In the case of lung cancer, mesothelioma, and pancreatic cancer, patients often don’t become symptomatic until the cancer is well advanced. As a result, the cancer has often metastasized and there is little hope of long term survival, even with modern treatments.